MF 35 Diesel Tractor

[cobbadog]

With the enlarging of the chamber, what size do you expand the originals out to without going over the lip of the liner? The pics show that the enlarged hole may have a slight 'squareness' to it by use of a file.

[allisb]

You going off that link pics Cobba? That's all the info that I have. But reading around it sounds like a fair dinkum exersize. I mean, it was on the internet, therefore it has to be true? 
Interesting one tho.
Rx

[AUSDOK]

Hi ,re piston direction, on disassembley ,I am sure that the recess in the pistons was facing the manifold,but have been told that they should face the injector side. sorry about the dumb question ,but I want to get it right. cheers Rudy

[cobbadog]

Yeah Rx, everything we read of the net is, well correct? Unlikely. The description on the enlargement was stated to be about the size of a 'pea'.
This story came from the Pommy magazine which I receive each month and is told by their resident mechanic, Ben Phillips who makes a living from restoring and repairing vintage tractors. I have no doubt that it works as he would have been shot down in flames by them over there ages ago if it made no difference or did not work.
I was unsure of the actual size before and after and was just curious.

[John 54]

Sorry a bit off subject. I was a mechanic in the oil industry for 35 years, when I had new mechanic to familiarize with the plant the first thing I told them. There is no such thing as a dumb Question only Dumb answers. That question you think is dumb might save someone's life or avoid equipment damage so ask it. And you would not ask it if you did not know the answer.
Regards John
PS Sorry but it is one of my pet hates, please ask all questions even if you think they might be dumb because they aren't, it might just  save you time, money or even your Life.
       

[allisb]

Yeah, Cobba. That true comment was certainly tongue in cheek. But I agree, that was a pretty fair dinkum bloke posting that head mod, so I'd be very tempted to try it if I had one.
However, we mostly don't get the same conditions of "cold" that they get overseas in some places. So maybe with good compression and well set up they may start ok? I certainly do remember seeing some over in NZ that were renowned to be slugs to start.
Cheers
Rx

[AUSDOK]

Hi interesting comments ,re asking dumb questions ,and I know you are dead right. In my trade assumptions cost lives and a friend of mine went through the process of a coroners court for no fault of there own. A very unpleasant experience. Does any body know which way the pistons face as I cant seem to find it in the pdf manual. Cheers Rudy

[wee-allis]

Hi Rudy, The recess in the pistons face the same side as the cam shaft.

Regards, Steve.

[AUSDOK]

Thanks Steve,hopefully will have a big day Thursday  on the tractor and see what we can manage.  Cheers Rudy

[cobbadog]

OK I will ask as I am a curious type, Is the cam side the same as the injectors or manifold.
I have a mate who says he is a bout to do one of these engines up and he was told it had a history of being cranky to start in cold weather. We might not get snow here in Taree and the surrounds but we do get below 0'c in Winter so he was curious about the conversion/improvement.

[wee-allis]

Hi John,

If these engines have good compression and a fuel system working as it is supposed to, my experience shows they will start easily in most instances, without using the pre-heat.

I recently rebuilt a 20C engine, the engine which pre-cedes this engine for a Vanguard. For the first time in many years, it now fires up, from cold, without the pre-heater.

Over the last 50 odd years that I have been twisting spanners, I have repaired many and owned several of these engines. (Some say I'm a slow learner). This is the first time I have been made aware of this modification.  It may well be of assistance in colder climates, but I very much doubt that it is necessary here in Oz.

Regards, Steve.

[cobbadog]

Sounds good. That reminds me I am guessing that the Vanguard is now a happy runner again.

[AUSDOK]

Ok tomorrow is the day we put it back together, the pistons where inserted the wrong way round ,I have looked at the diagrams ,but the orientation of the conrods are unclear ,  Cheers rudy

[wee-allis]

Hi Rudy, The con rod numbers face away from the camshaft and the swirl chambers on the piston head faces to the camshaft.
Steve.

[AUSDOK]

Hi Steve Thanks for the info ,another challenging day ,we measured the big end as 2thou over and they where stamped as such,we think. the supplier stated that that was impossible and supplied us with 10 thou over ,which where way to tight, so back to standard ,you guessed it to loose, so to get on with the job we reused the old bearings ,we previously has plenty of oil pressure and no noise.  We inserted the liners and pistons with no problems ,we pre tapped the cylinder head stud and bolt holes and after tightening the bolts to contact 2 broke .They must of been stretched and very brittle ,so covers on and will order new high tensile bolts. Could somebody please send me the dimensions and a photo of the original fenerator mountinf as it has been modified and I will need a new pulley for the generator as well. Cheers Rudy