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Forum Categories => Stationary Engines => Topic started by: cobbadog on 13 March, 2020, 09:29:48 pm

Title: McDonald Imperial Super Diesel
Post by: cobbadog on 13 March, 2020, 09:29:48 pm
Well here we go on a long journy with this one. I managed to load my preferred engine onto the tractors carry-all which made for power steering on the Cropmaster which was different and got it up under the carport which is where it will be stripped down and cleaned. I have found the good injector as the original was broken off by someone else many years ago and it took me over a year to find the replacement but at least it is here. I quickly had a look at what I think are all the parts I have and found parts that I don't know what they are as yet but in time with help from you guys I will find a place to fit them.
Now I do have a booklet called "Instruction Book for erecting and running Imperial Super -Diesel Engines" It has 35 pages of information but it is not a workshop manual that shows you what parts belong where.

Is there a workshop manual for the SE engine?

If so where do I beg, borrow or buy one from?
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 14 March, 2020, 04:15:59 pm
Well first we had to drag the best of two evils out from under the house, load it onto the carry-all and get it up under the carport. As you can see this is the broken injector.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 14 March, 2020, 04:33:04 pm
Next I started to remove some parts and started with the 4" belt pulley. Had a look inside and the 3 heads of the bolts were badly rusted and I had to use 3 different size sockets on the 3 bolts but they wound out as if nothing was wrong. I then thought this is off to a great start.
Big Mouth now has foot in mouth disease. Next to be removed are the flywheels and to do that the gibb keys had to come out. Ever since these engines came home years ago I have squirted diesel on nearly every bolt I could see including the flywheels and the gibb keys. Well the head broke off the first one. So with not too much swearing I started to drill out the key starting with a small one then bigger and then to the 1/4" size. I got this drilled into the key to almost the full depth of the twist of the bit taking care to keep pulling it out to clear the twist. Snap it went at full depth, more words of constructive and very descriptive usually pleasurable things flew around the yard. So Plan C was then to drill small holes above and to the side of the 1/4" bastard. So using now a 1/8" bit I managed to carefully drill 2 more holes full depth and the theory was to help relive the pressure on the 1/4" bit. Then it hit me, maybe I can cut away part of the gibb key and this will allow me to get some vice grips on the bit. No way, the bit didn't just snap it shattered into lots of short pieces so there is still about an 1" inside under the hub of the flywheel but this gave me more access to drill the small holes deeper. Well as you can see it too snapped off. So I now have 2 drill bits securing the key in place, I feel so lucky,,,,NOT!
You will see the good injector waiting to be stripped. clean and adjusted in the future.
Title: Re: McDonald Imperial Super Diesel
Post by: Austral on 14 March, 2020, 08:11:46 pm
Trying to drill out seized keys usually results in some form of grief.
Perhaps you could try heating  the flywheel hub to red heat and then putting a large tapered drift between the crankcase and hub if there is enough clearance to  do so.
Title: Re: McDonald Imperial Super Diesel
Post by: Austral on 14 March, 2020, 08:19:30 pm
If you heat the flywheel hub as is my previous post, first try knocking it off the key towards the crankcase. You may have to heat and cool a few times, but it is a proven method from a few years ago.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 14 March, 2020, 09:53:18 pm
Cheers, thanks for the tip. I have to keep trying any of tricks to get it off now. I will also try to partly collapse what I can of the old key. If I start to see some progress I can actually fit a 3 point puller and put a bit of weight on it too but not before the key starts to move out or the flywheel in towards the engine.
I can feel more strong words coming up, I think.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 15 March, 2020, 03:43:12 pm
Today I made up a tool to help flog the flywheel inwards after I get some heat into and around the hub of the flywheel. A piece of 3" water pipe with a handle attached and heavy bit of flat bar welded to the back end of it for the BFH can do it's job.
Started to heat up using my only source of heat a "B" size burner on a length of hose from the LPG bottle. I got comfy on an upturned 20ltr oil drum and started heating up. This is a slow process but then it started pissing down rain and guess where the water leak is, right above me. So I blew the whistle and went on with another job.
I have had a very kind offer of some oxy if required so time will tell.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 23 March, 2020, 04:13:20 pm
Been in contact with Stephen from Plough Book Sales and the only info he has ever had is this instruction booklet, but thanks for bringing it to my attention as this is how we find things out.
Well I went around to the opposite side yesterday and managed to do almost the exact same thing. Head broke off the gibb key and so far I have successfully drilled a 3/16" hole the key but not all the way through. After a lot of scratching around I actually found that the keyway in the flywheel goes all the way through but, it does not on the crankshaft. The crankshaft has a small step down in size where the back of the flywheel sits and you can only just see the groove in the shaft tapering off to nothing. This will make it impossible to try to knock the flywheel in towards the engine so that idea is now dealt with. Still waiting for the 10lb slide hammer to arrive and I have started to make an adaptor to use once it is here.
So I decided to also look at the oil strainer which didn't do too much straining like this. As rough as the soldering job looks it actually has taken to the stainless steel wire and bonded in place. At least this is done, phew.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 24 March, 2020, 04:30:24 pm
New toy arrived today to encourage the gibb keys to come out. This one is a 10lb one.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 25 March, 2020, 04:10:46 pm
Made a socket to adapt to the slide hammer today. This is my very first attempt to make a thread on the lathe and it is an internal one just to test my lack of ability. Pics are bad but they are what they are. Main thing to me is that it worked and screws on just right. Having zero experience at doing this I did manage to learn something and that is I must have had the boring bar slightly pointing away from me as I think the thread has a very slight taper even though I used the main carriage driven by the lead screw.
Shoulders back, chest out !      :o
Title: Re: McDonald Imperial Super Diesel
Post by: asw120 on 25 March, 2020, 08:17:23 pm
I have to do this, myself. Mine has to have two different threads, which will test me.
Jarrod.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 25 March, 2020, 09:30:03 pm
I have no idea where the short piece of pipe came from or why it was sitting in one of the tool boxes but it was the right ID and OD and length as other pieces in the kit so I decide to 'have a go ya mug'.
The 7/8" UNF is the big thread in this kit and the small size is 5/8" UNF which is only for the dent puller with the self tapping screw in it. It surpised me that it wasn't metric thread but at least I could identify it and copy the thread.
Next is to make the angle iron piece to slip over the bolt that has to be welded to the broken key. Was shown a link to a bloke called shopdaog sam on YouTube who has a lot of tricks up his sleeve for repairing so many things and gibb key removal was a 4 part story and informative. So soon enough I will be ready to give it a go, possibly over the weekend.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 28 March, 2020, 04:11:48 pm
Spent a little bit more time on these gibb keys today. I carefully welded a HT bolt to the key, placed a pipe over the lot and a heavy flat plate and wound the nut on. I watched in a video where he used a rattle gun to also help it come loose so out with the 18v rattle gun. This is the result, the key broke away at the end of the broken drill bits and level with the flywheel hub. Tomorrow I will go back to drilling more holes below the broken drill bits and then fit a puller on and try to pull the flywheel over the key.
So I went around to the other side and welded the bolt on and set it all up along with the new big bunsen burner which sounds like a jet when opened up and applied the heat then the rattle gun. The nut stripped. So now I am making up an attachment for the slide hammer on this side, heat again and then hammer away.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 29 March, 2020, 03:06:44 pm
Well after a lot of swearing and then some more swearing I finally got one out, the one on the starting side of the engine. It took a new home made adaptor, then had to beef it up again, a lot of heat from the big LPG bunsen burner some flogging with a cold chisel behind the welded on bolt and the new slide hammer and a sore back from bending over but when it came out I thought "you bloody beauty". Even after beefing the 5mm thick angle iron up on the sides you can see in the last pic how it has still bent after all the flogging on the weight of the hammer.

So with this win under the belt I was not about to push my luck any further so I packed up for the day and still a happy chappy.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 31 March, 2020, 04:14:37 pm
With no extra heat and with no effort at all this flywheel slid off the shaft. The gibb key must really be what holds these in place.
Now to the other side with the broken drill bits in the gibb key. I will drill some more holes under the 3/16" hole in the centre with the shattered drill bit still in place to weaken the key as much as possible. Then I will have an attempt at using a centre punch or a nail punch to loosen the drill bit/s. If no joy I will try to use a pin punch to start to collapse the key and then hook up my puller and put some weight on it and see how that goes. I spoke with a close friend about this side today and if the plan as described doesn't work I have been kindly offered the use of a 10 ton hydraulic puller to shift it, now that should move it !
Title: Re: McDonald Imperial Super Diesel
Post by: wee-allis on 31 March, 2020, 05:45:39 pm

John, unless you can collapse that gib key, you won't pull the flywheel off, no matter how much pressure you put on it. The gib key has a 1 in 100 taper on it to lock the flywheel.

Drill as many holes as you can, right through, no matter what size you can get in, then try to punch the rest of the key to loosen it. The holes will allow it to collapse.  Good luck with it.
Steve.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 31 March, 2020, 09:17:43 pm
Hi Steve, thanks for the heads up, I intend to do my best to collapse the key before trying to pull the flywheel. Time will tell how I get on.
Title: Re: McDonald Imperial Super Diesel
Post by: Austral on 01 April, 2020, 09:04:20 am
Well done on getting one flywheel off after a lot of grief.
Perhaps you could try spark erosion on the broken key.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 01 April, 2020, 09:29:52 pm
I do like spark erosion and had some done about 25 years ago at a local engineering shop. Unfortunately they are gone now and no one else has that service here. The other issue is the bloody weight of this elephant and is why I want the flywheels off so the block can go to town and have the liner pressed out, all pickled up nice and clean as there is half a tone of rust around the bore then a new seal fitted onto the liner and pressed back in.
I might get the chance to have another go tomorrow afternoon to drill more holes and start the collapse process otherwise it will be the weekend. As much of a pain this has been so far I am enjoying it because I am finding it more challenging than expected but enjoyable at the same time.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 04 April, 2020, 03:48:01 pm
This is what I started with today a punch, pobge and a 3/8" pin punch re-shaped to being a slotting chisel. You can one of the small holes opened up and another hiding behind swarf on the bottom right. After some very careful drilling I got the left hand side opened completely and a bigger hole on the bottom right. Centre and top right still have drill bits inside. Next it is time for heat, heat and more heat and bolt up the puller checking that it is an even distance off the flywheel as I expect to have to put some fetch on this one.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 04 April, 2020, 04:10:07 pm
After a lot of heating and smoke coming up from every where because of oil and grease, I bolted the puller in place and checked measured the distance off the flywheel to ensure it was square. I knew this was going to be tight, shit I hate being right at times but with the ol' trusty Sidchrome sockets, a "T" bar and wrong or right a length of pipe on the end of that. I put a fair bit of fetch on it and then got the 2lb soft hammer and flogged the outside of the flywheel and each time I was able to put just a little bit more on the pipe. Eventually it cracked and I shit myself and then studied what had just happened. All looked good, no stripped bolts into the flywheel and the centre bolt on the puller in tact I tried a bit more weight and it was easier. So I did a check measure on the end of the crankshaft and put some more strain on the puller and it became obvious it was on the move, at bloody last. It fought me all the way but it still a good feeling to see it slowly working it's way off. After about another 30 minutes of swinging on the pipe it was finally off, "YEAH TEAM COBBA".
You can see in what's left of the gibb key the remains of the small drill bit. It shows that it snapped when I was with-drawing it out to clear the swarf from the flutes of the drill. In the centre there is still a 3/16" drill bit hiding. As I was using the slotting chisel I made up tiny bits of drill bit kept falling out, it had truly shattered to bits.
On Monday I'm heading off to Manning Base Hospital and apply for a job as a "keyhole surgeon" these pics are my resume.
Title: Re: McDonald Imperial Super Diesel
Post by: wee-allis on 05 April, 2020, 07:36:01 am

Stubbornness and or persistence will win every time. Well done John.
Title: Re: McDonald Imperial Super Diesel
Post by: Austral on 05 April, 2020, 11:18:27 am
Well done again,patience and persistence have paid off.
By the way, gibb should be spelt gib, and not as in the brothers.
Perhaps you could tell us what a ''pobge'' is ???
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 05 April, 2020, 09:45:36 pm
The podge is similar to a metal punch but has a long taper with a rounded end. It was bought when I was playing panel beater and was used to align bolt holes. Probably has 6 other names but this was what it was called way back then.
Title: Re: McDonald Imperial Super Diesel
Post by: Austral on 06 April, 2020, 08:49:12 am
My thoughts were that '' pobge '' probably referred to ''podger'' of which I also have a couple of in the workshop. However the spelling had me intrigued, so I wanted to check out the true meaning of this mystery tool. Thanks for the clarification. 
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 07 April, 2020, 03:52:48 pm
This is where it is at now. I removed the hopper which took some doing as the gasket had a good hold on it. The 3 bolts that held it in place snapped off due to rust, surprise. Then I started digging out the rust from around the cylinder. So far I have remove 2 x 2 litre ice cream containers of loose flakey rust and this has got me half way down past the bore with a lot more to go. At least now I can see the small brass elbow to connect the oil primer line to now. Next was time to remove the crankshaft. I undid the nuts on both side covers and got one cover to move away fairly easily but the other side where the gears and oil pump are was a bit more tricky. Eventually it let go to expose a huge mess inside. Because this engine has not run for many years everything in here was dry as a  bone to a point that it was almost carbon black again. It was very thick so I scraped a lot out and wiped the ends of the gears to find the timing marks from the crankshaft to the cam. There are no timing marks for the governor or oil pump. I mention this because I have come across one engine that required the oil pump to be timed with the spark of the engine and this was the David Brown 30C engine. It had to be timed so the offset tang of the distributor would engage with the oil pump.
Next it is time to remove the gears and get inside for a clearer look.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 07 April, 2020, 03:54:51 pm
Nice mess in here to clean up. Believe it or not the pipe is on top of the governor shaft and it is as free as a bird to operate.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 08 April, 2020, 03:44:19 pm
Crankshaft out today.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 08 April, 2020, 03:46:09 pm
IT runs a pair of bronze bushes for the mains with an oil gallery machined inside for lube but the big end is made as bearing shells but in bronze (2 halves).
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 08 April, 2020, 03:47:04 pm
big end
Title: Re: McDonald Imperial Super Diesel
Post by: winchester on 10 April, 2020, 11:08:00 am
Yes well I feel that this subject has well and truly reached it's  used by date !
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 10 April, 2020, 03:53:09 pm
YES WELL,

Why is that Goosie?
If you don't like it then don't open it.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 10 April, 2020, 03:59:08 pm
Regardless of the comment by "The Goose" I will continue.

Today has been a day of cleaning up the carbon black from the side covers, removed one of the crankshaft seals and pushed one of the main bearings out far enough to clean up the blocked oil galleries
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 10 April, 2020, 04:15:31 pm
Next I continued to clean up the crank, the big end journal had light surface rust and cleaned off with some fine wet n dry. Then I cleaned up the big end set up and you can see the 3 shims that will sit between the big end bearing carrier and the bottom of the conrod which you can add or subtract the shims to alter the compression ratio. Then I bolted it in place for safe keeping, only a bit better than finger tight.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 10 April, 2020, 04:22:21 pm
Finally for today Mr Goosie if your still insisting on reading this;

The crankshaft looks worse than it actually is. The pitting is not too bad and is certainly good enough for a rally engine to run on and I have coated it all with a lick of Lanox. The brass tube with a copper nut, which is back to front to what oil and fuel lines are is from the oil primer. It still screws onto the brass elbow by hand which did amaze me. It has come adrift from the oil primer and I can see where it was soldered into the primer body which appears to be brass or a bronze. I was going to solder it back into place but then realised that the union nut will not fit back through the hole in the side of the hopper.
So I need to ask how is this usually done?
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 11 April, 2020, 04:22:32 pm
In today's episode of the expired used by date topic, the saga continues.

Yes well, today it was time to remove some broken studs that hold the coffee pot hopper in place and the ones that held the oil primer on. Plan of attack was to heat up one at a time add some Lanox to cool it and draw the product down into the thread and heat it again a few times, then use the stud extractor and wind them out. Worked perfectly on the first 2 but #3 snapped off. So out with the drill and find centre and start drilling. I took it out so far then tried an easy-out (extractor for some) and it was too tight so I kept stepping up the drill bit size and finally the old stud let go by winding itself down and into the hopper. Then I got out the 3/8" BSW tap and cleaned out the threads
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 11 April, 2020, 04:35:04 pm
Then it was time for the oil primer studs to be removed. Again threads cleaned up with the 1/4" BSW tap. how would the brass tube have been fitted into the primer originally? I think the tube is thick enough to be brass threaded tube and may have been screwed into the primer. Any thoughts?
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 11 April, 2020, 04:45:11 pm
Next was the moment that scares you when you see it, the reason why the engine was shut down for the last time. It was hard to see with all the crud covering it up but once removed and cleaned up you can see why. What had happened is the roller that runs on the cam seized solid and simply wore away the cam and that would have meant that the valves would not open as designed and cause loss of power. The roller and the slide it is attached to is now cleaned and free to work and ready to be put back in place when it is time.
Question; what is the best welding type to repair this? MIG or a certain grade electrode for the arc welder? It will need to be built up a bit to be level with the part of the cam that still is at original height.
Title: Re: McDonald Imperial Super Diesel
Post by: famous fitter on 11 April, 2020, 06:01:40 pm
Hi Cobba,

Try find another cam ? If not I?d use a cast iron rod with pre heat to build up and carefully grind and Linish smooth to original profile.

Don?t use a mig welder on cast iron ever.

It?s amazing the things you find when doing up an engine - how bad things can get and they still ran !!!!

Keep us posted on your progress

Cheers Justin
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 11 April, 2020, 09:51:08 pm
Thanka Justin, Cast iron rods it is then. I am not in the mood to start to remove another flywheel off the 2nd engine as yet. I still have memories of removing these 2 mongrels.
Going back to old school electrodes, would they have had a white paint on the ends? From my failing memory yellow was for stainless but for some reason I have a small number with white on the ends. As Dad was a welder, unlike his Son, I inherited all the toys from his shed and a number of welding rods came home with me and most are general purpose  6013 from memory again.
Thanks for your reply.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 12 April, 2020, 04:08:13 pm
I have been around the world and back with this issue on other Forums and one of the ideas put forward was also suggested by my wife Dee, make a larger roller. I dismissed the idea at first as I did not have that off the engine an I thought that the roller would be mounted in between a the push rod for added support but NO, it is simply bolted onto the side of the push rod and there is room for a larger roller to be installed.
So at the moment my thoughts are to make a larger diameter roller and dress the cam surface to get rid of the lip that is left at the moment. I have a hardened block of steel that followed me home one day as an unwanted off cut and this would be ideal to use.
Any thoughts on this idea?
Title: Re: McDonald Imperial Super Diesel
Post by: wee-allis on 12 April, 2020, 06:59:54 pm

John, no matter how big you make your roller, it won't lift the valve high enough. it is the height of the lobe on the cam which controls the valve lift. If you don't either re-build or replace the cam, it will never work correctly.  The height and duration of the cam lobe in any engine is critical to that particular engine.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 12 April, 2020, 09:25:43 pm
Thanks for that Steve, looks like its abck to buying some rods.
Title: Re: McDonald Imperial Super Diesel
Post by: wee-allis on 13 April, 2020, 08:00:48 am

And don't tell Dee, "See I told you so". That wouldn't be nice.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 13 April, 2020, 04:07:25 pm
Too late, she knows, she knows everything didn't you know!

Anyway, I have been just like a women going backward and forwards changing my mind on a whole heap of things so long as I don't start shaving my legs I think I will survive this turmoil.
Today I stripped off the oil pump and then cleaned out the sump and the area where all the gears run, what a bloody thick mess was inside here. So as it is now is good enough. As things came apart I found the shaft that the cam gear runs on has a slot machined in it for lubrication was choked so that part is cleaned up now. The oil pump was hiding so much crud behind it I could not believe that it just kept on falling out as I scraped away. So after cleaning up the pump I stuck it in my hand basin where I work and submerged the pick up of the pump and spun the gear by hand slowly. Nothing happened then wound it back the other way and presto, it works. Spun it faster by hand and the water spun out like a hose so when it get oil back inside it certainly will pump well. I blew out the water and filled the inside with Lanox then sprayed the outside as well. Next was the oil pressure indicator on the outside of the engine. It was stuck in the IN position so with a bit of Lanox on the outside and I turned the brass elbow that connects to the oil pressure line to facing upwards and filled it with Lanox and left it for a few hours. At last the small button that is suppose to extend out when there is pressure was freely moving. So when it is all the way out I filled the elbow with Lanox and pushed the button in and it pumped out the Lanox so this looks like it will work as well.
Next challenge apart from the cam gear is the water jacket around the cylinder, this will take a lot of doing but I have a very cunning plan for it.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 13 April, 2020, 04:08:35 pm
more pics
Title: Re: McDonald Imperial Super Diesel
Post by: Austral on 14 April, 2020, 09:16:26 pm
A couple of thoughts for a couple of problems.

I think you will find that the gear and cam are more likely to be cast steel rather than ordinary cast iron. A simple test with a file will show what it is.

Personally, I would be inclined to check the cam from the second engine, assuming that both engines are one and the same model.
If the flywheel key heads are in good order, you should be able to get them out with a proper tapered drift held in place by a G clamp.
This is a proven method that works. If they are stuck, again use a lot of heat on the flywheel hubs. They really need to be at the red hot stage around the key area to loosen up rust in the keyway.
If the key heads are badly damaged, then resort to welding a bolt to what is left of the key and use a serious slide hammer, but only after the heating process as suggested. That will minimise risk of breaking the key.

To remove compacted scunge from the bottom of hoppers below the cylinder, I have used a length of wire from a coat hanger with an inch or so bent at 90 degrees at the end. This is put in the drill chuck and run at high speed. The wire will eventually break due to the continuous flexing, so then start again as many times as you have to.

Good luck and I look forward to further instalments.
   
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 15 April, 2020, 10:09:18 pm
Thank you for your input. If I can avoid removing another flywheel I will. Your idea is pretty much as I did in the first instance but the steel just fractured then bent over and that was that. So that was when plan B, C D and so on came into play. Also sounds like I need to do an isolation walk one night with bolt cutters and find some #8 fencing wire. There is also the drain plugs at the bottom of the hopper one is damage and the other is complete so I will be removing that to gain access that way too
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 18 April, 2020, 03:30:34 pm
After shaving my legs and putting on my skirt to do this quarters BAS
I started digging towards the bottom of the hopper. First I had to remove the drain plug on one side as the plug on the opposite side is broken off flush with the block. Then slowly drove the long screw driver into the mess to loosen it and lift it out. All the time digging away at the scale on the sides. So far with one side down to the bottom and not clean as yet I have half filled a 2 litre container up with crap. Start on the other side tomorrow.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 19 April, 2020, 03:26:57 pm
Been at it again today and got to the bottom of the hopper and removed about another litre of rust and dirt out. I started hosing out the dust and then kept poking rods down and across the hopper along the sides and underneath the cylinder. The holes for the cooling of the head allowed me access to get under the cylinder and break away the rust scale. I was using a small magnet to lift out the chunks of rust and the hose to wash away the dirt.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 19 April, 2020, 03:28:32 pm
oops a double take.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 19 April, 2020, 03:41:00 pm
Then I used some button head screws and silicone to block the 5 holes that cool the head and a bit of flat bar iron and silicone to seal off the oil primer hole. Once cured I will start with a molasses bath to see if this helps clean the rest up. Before plugging the cooling holes I used them to put a rod through to get under the cylinder and I had to use a hammer to break away rust scale from the cylinder to the base of the hopper then a small magnet to lift out the chunks of rust scale.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 20 April, 2020, 03:50:35 pm
Got the hopper all cleaned out nicely and is now soaking in a molasses solution to treat the rust left on the cast iron. When you fill it up it looks and smells good enough to drink, just like a good Tooheys Old Beer, holds a head too for a while. Worked out how this governor goes back together, it took a while because I did not strip all of the engine down and parts of re-assembly are a guessing game.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 23 April, 2020, 04:35:09 pm
Started on the piston today. Cleaned it up a bit and found a unique way of removing the rings over all those ring glands by using the ring compressor back to front and it worked well. Piston is stamped with STD on top and has nothing to do with any diseases that get around. I stacked up the rings that came off the piston and roughly leveled up one end and found the other ends are all over the place.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 25 April, 2020, 03:52:50 pm
1st up today was to drain the hopper of the molasses mix. It held a good head considering it has been in there about a week. Once drained and rinsed it was not too bad, still some flakey rust but good enough for a "Weekend Warrior". I started to measure up the width of the ring glands. I was told that they are 1/4" but these ones are only 3/16" wide. The top ring gland measured in at 1/64" wider due to a bit of wear but it will remain the same. Even though I have a set of digital calipers they measure imperial to the decimal point and that is too hard for my head so I used my good  almost unused drill bits and they are a quick reference point.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 25 April, 2020, 04:14:29 pm
Then it was time to play with the bore. It had a lovely layer of crap top to bottom and wiping it out alone did not even look like removing it so out came my small El-cheapo, spring loaded honer. Just connect to the drill and add some diesel and away we went. You can see the sludge that it was removing, no wonder I thought I saw a mud crab early in the rebuild. Once cleaned up enough that it was smooth at least I decided to trial fit the rings that were on the piston that was not in the engine when I got it and I now know why. Remember the stack of rings I made with the ends almost in alignment and there were 2 that were longer? Well as it turns out the short ones have a gap of 0.060" and the long ones overlap by at least 0.100". Going by a quick Google search it suggests 0.004" / 1" diameter of the piston. Piston measures the 3.5" exactly as it should with STD on the top so that equates to 0.014" ring gap. So with a bit of work I can get 2 of them down to size but I found a bloke in Wyee NSW who I spoke to today and he can supply the correct rings once the factory goes back to work and he brings them in from N.Z.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 25 April, 2020, 04:18:52 pm
To finish the day off I had a respectable bore but then looked at the sump drain to see what I need to plug that hole. When I first looked the hole was smooth which could not be right so with a wash and a good light I noticed the pipe had been broken off flush so out with a hacksaw blade and cut the pipe and use my new trusty home made slotting chisel to collapse the sides in and knock out the thread.
Title: Re: McDonald Imperial Super Diesel
Post by: Austral on 25 April, 2020, 10:09:23 pm
With due respect, you were actually measuring the ring grooves and not the ''glands''. We humans have them for various functions of the body. The correct wording is ''lands'', which is the raised portion between the grooves.
I hope your rebuild ends up much better than a lot of the smoke belching, oil spewing and fuel dribbling environmental terrorists that are seen from time to time. 
Whilst not familiar with all of the McDonald models, I know that those with the Hvid/Brons fuel systems can cause a lot of problems to owners with little understanding of the type and unfortunately, knowledgeable people for these seem to be hard to find these days.
However, I wish you well and hope to read the next instalment soon.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 26 April, 2020, 04:36:14 pm
Cheers thanks for the English Grammar lesson, I do need it from time to time. I have heard similar stories about these engines and that they can be a very finicky thing to start and or run and keep running, I can only compare the stories I've heard with them being very similar to a Jelbart engine, only run when they feel like it.
I would prefer some smoke from the exhaust as it makes it more authentic and could upset some people. Last year there was a Petter twin that was dragged into the engine compound on the Sunday morning just before the World Record attempt for most stationary engines running at one time. It passed scruitineering but boy it used a lot of start ya bastard to get going and I'm sure that by the time if finished the record attempt and it did the sump must have been almost empty, it smoked like no tomorrow.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 26 April, 2020, 04:37:06 pm
So today I had an easy day of play time cleaning up bits and pieces and actually bolting the engine oil pump back into position, fitting the rebuilt oil pick up with it's new strainer and connected the oil pressure indicator and the oil lines for the bearings. Then I saw the split in the nut. So I have it off the engine and will dig out some new copper pipe and look at making a new line with later model fittings on the end.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 27 April, 2020, 03:54:17 pm
Today was time to mount the engine onto the transporter before it got too heavy.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 27 April, 2020, 04:16:12 pm
Then I have been waiting to get this part of the engine, the head. Before I even start cleaning the head up, I noticed that the cooling tubes for the head were not as they should be. Some were sitting just as they should and others nearly flush and not good enough to seal using the "O" rings. So went into the shed and dragged out some copper tube and made the decision to remove all the old ones and fit all new ones with a bit of Stag Jointing Paste, love this stuff. So I cleaned up the old copper pipe and collapsed the original brass tubes, cleaned the holes and knocked the new tubes into place. Then I went looking for the taps and dies to clean up the threads for the head. It is 3/4" UNC and that's exactly what was the largest size in that box. I ran the taps through the nuts and they cleaned up nicely but I did not have a die nut only the round die so an improvisation was called for. So instead of a die nut you have a nut using a die. I started the die by hand then placed the 2 screw drivers into the holes and used my big long screw driver to turn the others around while holding the handles tightly together. It was quite easy as it only had to remove rust not cut a new thread. Now the nuts wind on all the way by hand, yippee.
I don't know why, but I feel as if it is really moving along right now.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 29 April, 2020, 04:01:11 pm
Sometimes it is all the small jobs that take most of the time. Today I borrowed the Rolls Royce of flaring tools to make the new oil pressure line  to the bush on the crank shaft. I bought a new nut to replace the split one so I dug out a short length of 5/16" copper tube, cut it to length flared one end put on the two new nuts then flared the other end. Then dug out my small tube bender and made the basic shape required and bolted it in place. Lastly the thread for the sum plug was a bit how ya going so again I borrowed the tap to clean that up.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 02 May, 2020, 04:13:15 pm
Spent part of today cleaning up threads of the studs on the head and did a trial fit of the head to the engine to check that it would go over the new copper tube and it did. Then dug out part of the linkage system just to see what it would look like. I now need to clean up the linkages that I have to see if it is all there and I think it is. Also had a look at the coffee pot part of the hopper and cleaned up the 2 small 3/16" studs that hold the fuel tank in place.
Yesterday I bought home a pair of Speedi-Sleeves to fit to the crank shaft as the grooves in it for the new seals were a bit bad.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 07 May, 2020, 04:17:44 pm
Been soaking the injector to get it apart then cleaned. I have the top section and that needle out and free but the bottom one is rock solid. It has been in some thinners for a few days and the 2 hoes in the injector cap are now clear and the cavity behind is clear so the thinners is working from both sides now.
Looks good for the oil primer from a member here, so thank you for that. I need a few dimensions for a fuel tank and although I have the cast iron casting for the air cleaner I am after the outer housing if one is king about please.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 09 May, 2020, 03:27:32 pm
To try to remove the bottom needle from the body I made this tool up. It is a piece of 3/8" rod drilled to being undersize to the top of the needle and a slot cut in it. In theory I should be able to lightly tap the tool onto the needle and twist and lift out the stuck needle, hasn't happened yet and the next post will show why.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 09 May, 2020, 03:37:24 pm
I did like the flame that came out the bottom but when I turned it arse up and really got into it with the heat it went off like a flame thrower. By the time I got the camera out it had backed off to being this sedate little display. Once it had burnt out I continued to get serious with the heat and then I found the lump of crap that fell out. Once cooled I sat it on top to take the pic.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 10 May, 2020, 04:08:09 pm
Did some work on some of the brackets and linkages and mixed and matched the best pieces and used the return spring that was on one of the set of brackets.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 10 May, 2020, 04:24:34 pm
Next it was time to experiment. Still having no joy with getting the needle out of the bottom of the good injector I went investigating with the broken one. The bottom part of the injector housing was snapped off and stuck firmly in the cap. I lost many hours and brain cells trying to get inside. Tried many different ways of achieving what it almost too all day to get to.
In the end I knew it was to be the death of a cap but I had to learn something today. So eventually into the drill vice and away I went with the 1/4" drill bit, down deeper and deeper until I felt it go through but it was not the cap. So had a look with the good led light and nothing so I kept going and eventually the bloody housing finally let go and collapsed in and it was out.
It was then I found that I had drilled past the bottom of the housing and into a cavity in the cap. So that was the death of that cap but the good one is still intact as this is all about 'learning' I hope. So with the broken bits out of the way a copper washer gasket also fell out confirming I went way too deep and now left with a cap and a far better idea and a new plan to get this bloody needle out.
I forget what letter of the alphabet I'm up with all the plans I have gone through but lets says I might be learning the Greek Alphabet soon. New plan is to drill a nice neat smallish hole dead centre in the cap and push the needle out from that end then weld the small hole up. Any comments on this would be gratefully appreciated before I jump into the fire.
Pictures below are the old cap and is the sacrificial lamb as an aid to the education of a nutter.
Title: Re: McDonald Imperial Super Diesel
Post by: Austral on 10 May, 2020, 09:44:56 pm
May I suggest that you read up on the Hvid/Brons fuel system. There is comprehensive reading to be had on the internet, if you have not already done so.   
You could also try electrolysis for freeing up rusted and seized components. This has always given me good results in the past.
Title: Re: McDonald Imperial Super Diesel
Post by: asw120 on 12 May, 2020, 03:33:53 pm
A late member of another forum built a scratch Brons / Hvid engine.
Googling "homebrew hvid" should get it. By the time the whole story is read, one has a full understanding of the system.
It seems McDonald kept it going longer than almost anyone else.

Jarrod.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 12 May, 2020, 04:23:10 pm
Thank you both for the tips.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 16 May, 2020, 03:34:50 pm

To day I decided while waiting for the electrolysis to hopefully work on the injectors bottom needle I started to make a new pin for the rocker arm to pivot on and add a better oil hole for lube by cutting a groove in the shaft and boring an oil hole halfway down the pin and then cross drilling it. I also reground the end of the rocker arm where it meets the valve stem. Next is the pivoting ball, this will explain itself in the future pics but I may need to make another push rod from the cam follower through the pivot ball to the rocker arm. You will notice the old brazing repair from long ago but this one is better than the other one I have to choose from so this is it.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 17 May, 2020, 02:40:15 pm
Played around with the linkages today cleaning up the parts and making a special collar to hold the fork from another linkage that operates the injector. I think it is all ready to go together when more parts arrive and try to work out how to adjust it all.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 17 May, 2020, 02:52:56 pm
While still waiting on the electrolysis to do its thing I played around with some ideas or experiments, why not I say!
First was to see what happens when you use a MIG welder on cast steel, well it looks as if it welds. I will give it a flogging soon to see what it takes to fracture. Some of the valve stems were badly worn on the ends so again what happens when you weld these up with a MIG.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 18 May, 2020, 04:05:22 pm
So as I am waiting for parts and my head keeps jumping from one job to another this was play time for today. Straight from the "why not" department and it will come in handy later on for the air cleaner that I have to make. Never tried doing this before and for a first attempt it is ok so this will be it, rough n ready. Tried a few ways to get the little punch to work and in the end I simply cut the sheet metal with the 1mm cutting disc then introduced the punch while holding the sheet metal in place with some flat bar iron and clamps.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 22 May, 2020, 04:15:04 pm
To continue with the "have a go ya mug" attitude and after being inspired by Ian Rowsal of Custom Garage I decide to have a go at this today. Found a couple of pieces of timber and cut the shape out then made a sheet metal sandwich and used a hammer to dress the edge over to make the lid. It surprised me that it worked so this is my new lid and tomorrow I will attach it to the louvre sided section I made the other day.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 23 May, 2020, 03:37:38 pm
Rough enough is good enough for this old engine. I made the centre mounting shaft then soldered the top onto the cylinder and this is how it ended up.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 27 May, 2020, 03:42:51 pm
Cleaned up the outside of a paint thinners tin to use as the fuel tank. I think it is about 1 litre bigger than standard so it is a long range fuel cell now. I have strengthened the bottom where the tap will go in and made up the mounting brackets to the hopper.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 29 May, 2020, 04:24:35 pm
Cam gear is home and I started to linish it to shape.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 30 May, 2020, 03:50:08 pm
The next bit of dribble for today after work gave me just enough time to linish the cam profile but I found a couple of spots that need to be built up higher. The guy who welded this must have known as he mentioned that if I needed any part built up just bring it back, so it will go back to him next week.
Then I fitted both Speedi-Sleeves to the crankshaft. This took all of 5 minutes. I picked up a piece of exhaust pipe that was the correct ID to fit over the sleeve and a couple of light taps to get both sleeves into the correct position.
Not much play time today but at least something got done.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 31 May, 2020, 03:37:11 pm
Well I went back to the job of removing the fuel cup from the injector body. Had no luck with electrolysis only that it is super clean on the outside. So there was no way that the small grub screw would undo even using an impact socket with the screw driver bit in it so I drilled it out of the way. After reading about so many different ways to achieve what I am trying to do today I went down the road of heating and quenching. Using what Dad used to cal a size C lpg burner I started to gently heat the cup and then quench it in water. I did this a couple of times and the last time I gave it full throttle and got the cup to the dullest of cherry red and then quenched it again. Then I left it sitting in water until next time where I will once again look closer at how much I have drilled out and if any more needs to be removed then will go back to the serious heating again. All the time I have been very gently tapping the cup to see if it shows any signs of moving. This tapping is dangerous as this is how the other cup was broken off the injector body, not because of tapping it directly but by using a lever to lift the body out of the head and the slightest movement sideways breaks the cup off. In the instruction book this is made very clear and that when you remove a stubborn injector it is a case of removing the head and prising the cup up.
So this is my SpacEx clean burn launch today.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 01 June, 2020, 10:34:13 pm
Oil primer arrived today and is in progress to get it functioning again.
Thank you Jarrod.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 08 June, 2020, 03:43:50 pm
Well I stripped the oil primer and had to remove the plunger from the brass tube, clean it all up and as suggested I simply reversed the plunger so that it was back to original specifications and not with all the wear on it. I tinned the end of the brass tube and sweated it back in place without having to remove the outter casing by heating it up through the bottom where the check valve should have been. I welded the plunger back into the cap then made a new gasket to fit between the body and hopper. My brass tube was still there so I made it to the new length as it was a bit too long, tinned it and again heated the brass tube and soldered it back into the body. Some silicone and then bolted it back into place.
I did a test on the bench by putting some oil in the case with the plunger installed and sitting down. No oil came out. I started lifting the cap up and down and it started pumping oil out so it is a win. It is amazing how much oil it displaces each pump.
Title: Re: McDonald Imperial Super Diesel
Post by: winnock on 09 June, 2020, 03:34:52 pm
John. I have been thinking about your injector cup. We all know how well tapers lock together when the angles are right. The chuck in a lathe tailstock is an example. I feel it is not corrosion that is holding the cup on. When you applied heat I think both the cup and injector body were expanding together and the taper lock remained. How about placing the injector in a freezer until it is thoroughly chilled. Then hold the injector over a pan of boiling water with the cup immersed. You could even tape some insulating material around the body to prevent heat from expanding the body. The cup having much less mass than the body should expand and hopefully come free with a little persuasion.
Hugh
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 09 June, 2020, 04:00:28 pm
Cheers Hugh, I will give that a go as well and thanks for the suggestion. I have been doing other things around this issue while I think about what to go back to and start again. I will also have a better look using a magnifying glass to look at the screw I have drilled out that holds the cup in place. It is an unknown size so I have been taking it out in 1/64" at a time an I think I am at the size but don't know for sure.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 12 June, 2020, 04:49:30 pm
Plan B for the fuel tank, one bomb proof tank.
I have the injector body hidden in the freezer where hopefully it won't be found until I get it out of there tomorrow and no one will know. It is wrapped up in a plastic bag so hopefully it is not being thawed out for tonights tucker.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 13 June, 2020, 03:56:24 pm
I WON, I WON !
I got the bastard at last. Safely apart now just zapping the needle from the tube and it is ready. A heap of filth was still inside the cap and could only get in there via the fuel system. What worked was the freezing of the body and heating the cup. I did also find a small amount of the old screw in the recess that was holding things up a little bit once I got it to twist and it showed up so I dug it out.
Also finished off the lid for the bomb proof fuel tank.
It is a good feeling when things go forward after a long challenge, so happy I could shit!
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 14 June, 2020, 04:44:21 pm
Tomorrow I will take the head with me back into town and see if I can get him to accurately measure the guides and I am looking at getting some over sized valves made, this may be the simplest and easiest way to go.

Having endured the day without power because they replaced a transformer down the bottom of the street I could not do the jobs I wanted to do but did get to shuffle a heap of curtaining fabric around in Dee's work room. So when I finally got to play mode I had a go at removing the needle from the stem after being in the electrolysis tank for a couple of days. It did come out sparkling clean but obviously still a lot of carbon on the inside. I have easy access to the bottom of the needle via a hole where the fuel would run into the cup, also can get a good hold on the top of the needle but it is not budging yet.

In the McDonald hand book of instructions it does mention a few times to use 'kero' to clean the fuel system parts in. Why this is suggested rather than clean diesel is a mystery to me. So it is soaking in some kero at the moment. I am also now eyeing up my ultrasonic tank as I can actually touch it now some fabric is gone. so find a plastic jar and some petrol and spark it up, literally not physically.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 15 June, 2020, 04:07:24 pm
The McDonald valve guides are an odd shape to say the least. With that step in the top to hold the valve spring in place, the wide shoulder to stop it going down the hole in the head then they differ in length as to how far they protrude into the port area.
The widest point they are around 28mm on that shoulder. So today I found a supplier of the cast iron and it will be on its way soon. Spoke to the engine bloke today and he removed both guides so they can be copied and also spoke to Bills Motor works about the supply of some new valves. Bill was out doing a walk-about and he will get back to me soon, I hope along with some good news about the rings for the engine too. So maybe some progress is about to happen again.
Back to that needle soaking in kero. This seems to do nothing and a very generous hit with carby cleaner also has not shifted anything so far. So the plastic jar of petrol and into the ultrasonic tank looks to be the next step.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 16 June, 2020, 02:47:35 pm
This is the new fuel tank that should be bombproof against any blow back from the injector. Just adds more weight to the transporter but should work well.
Also this is the condition of the new piece of 30mm wide flat bar iron acting as the anode in the bath tub. This is just 1 days worth of crud and the amount of pitting under all that stuff is amazing.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 17 June, 2020, 02:42:25 pm
Cam gear is back and linished to what I think is the correct profile. At last the needle is out of the tube after a very hot episode with the big bunsen burner. The needle came out a little bent so I did straighten it but I do have the other needle to use if needed. Good news with the valves and rings and the valves should be confirmed tomorrow with luck.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 18 June, 2020, 04:07:20 pm
Got a little bit done today. I used some valve grinding paste both coarse and fine to re-seat the needle by hand and it now has a lovely shiny taper all the way around. This, I hope will minimise any compression blow back. I will pick up some copper washers (gaskets) tomorrow hopefully while driving around for work along with a new compression spring for the needle. This one looked ok but during the electrolysis process it cleaned up the rust very well and made the gauge of the wire too thin and it broke. I don't expect this to be hard to find and replace. (foot in mouth disease possibly coming on).
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 20 June, 2020, 04:17:36 pm
Assembled the injector today with the new spring on the needle, new copper crush washer that has been annealed to make sure of a good seat plus the roughly made grub screw which works a treat. The grub screw does not hold the cup in place but rather directs the spray into the combustion chamber inside the head then on top of the piston. When the injector is bolted down this is what seals the cup against both copper washers as there is another one to be fitted on the outside of the cup and sits down against the head. That is the lump of cast iron ready for valve guides and I nearly have the valves sorted, I hope.
Something I discovered when assembling the injector is that it works opposite to how I though it would. Once the injector body was assembled it was holding the needle in the closed position and I stripped it again trying to work out what was wrong. Then the penny dropped and the top of the injector is lifted to open the needle to allow fuel inside. Well I hope that is how it works.
Title: Re: McDonald Imperial Super Diesel
Post by: asw120 on 20 June, 2020, 05:10:43 pm
When you get it together on the engine, you may wonder if you did something wrong when the injector barely moves even on full governor. Fear not; the thing is only lifted maybe 20 thou for full blast. While running, a 10 thou feeler gauge slipped under the injector lifter will have it throttling up smartly.

Jarrod.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 20 June, 2020, 09:43:51 pm
Thanks Jarrod for confirming my theory about its operation. It threw me at first but thought about it and then the penny dropped, at last.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 22 June, 2020, 04:06:17 pm
Good news today about the valves. The ones he has will fit so I have ordered them and asked if he would send the valves and the rings set once they arrive. He confirmed that the rings for the McDonald did not make the last order but they are in production now in N.Z. so once that order is complete it will float across "the ditch" and come and join the fun here.
Title: Re: McDonald Imperial Super Diesel
Post by: cobbadog on 26 June, 2020, 03:41:13 pm
Took the advise to change the spring on the needle which was a gauge heavier than the original. So I fitted the smaller spring today and cut out the new cork gasket for the water hopper.