Slow Speed Diesel Engines > Other Slow Speed Diesels

McDonald Imperial Super Diesel Crude Oil Engine

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I am about halfway into the rebuild of this McDonald 2.5HP crude oil / diesel engine. It left the factory in Victoria on 18th May 1945 so it is coming up for its 75 birthday soon. It was donated to me, well a pair of them were, in the hope that one day I would bite the bullet and get one running, that time has come. It uses a Hyvid / Brons fuel injection system which is a tricky bugger on a good day and of which I know next to nothing about as yet. It took close to 4 days of hard yakka to get the flywheels off as the Gib key heads broke off easily and then it was a case of welding a bolt to it and a slide hammer and the other had to be drilled out and then collapsed. So far I have been at this for around a month and a half found the reason for it being pushed into a corner as the roller for the cam seized up and then wore that cam down and that stopped opening the valves enough to make power. I have had the engine for a minimum of 5 -6 years looking for the damaged or missing parts and the biggest issue was the broken injector which I managed to find one.
Other missing parts but promising just recently are an oil primer for pushing oil down through the water hopper to the piston, rings and gudgeon pin. A cap for the crank case lid which I think I can make and a fuel tank again will make. I've ordered a new set of rings, 6 in total for this engine and have been making new gaskets including the head gasket as well.
I will post a couple of pics of this monster, small in size but bloody heavy when assembles as the 2 engines in the box trailer rated at 750kg flattened the springs.
These pics show both engines waiting to be looked at,drilling the Gib key and finally getting one out and the absolute mess inside the gears.

Finally today is the unique piston, conrod and big end bearing set up. As you can see you can adjust the compression ration by adding or subtracting the shims. Then a pic of the worn cam gear.

If it really will run on crude oil, I believe the big oil co's can't give it away at the moment!

Well done Cobba, thanks for starting this thread.  I shall be following with interest.

Thanks for the feed back guys. Everything on this engine is heavy and when you go to pick something up you have to be certain that you have a good hold of it. Even the side cover over the gears is solid cast steel and not cast iron so it is that but extra in weight. So far the only light parts are the ones I don't have. All the oil pressure lines were brass tubing as well as the oil primer line but that and one of the high pressure oil lines (all of 7 psi) are now 5/16" copper tube.
Made the ehad gasket today as well. The gasket is a simple ring shaped gasket 1mm thick and fits into a recess in the head and then the top of the bore fits into the recess to seal it off along with 5 "O" rings around the new cooling tubes I fitted into place at the top of the bore. When I can I will put up random pics of the nightmare I started with but we are now slowly getting an understanding that I don't like coming second and this engine will run once again.
My absolute biggest test is yet to come, all of the linkages for the head and injector.


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