Hope someone can help, I have the engine for the tractor all stripped down
apart from the clutch unit for the donkey start mechanism will not come
out of the housing. The housing has been removed from the main engine,
the donkey engine has been removed, I have removed the 4 bolts securing
it to the housing but it refuses to move. Am I missing something ?.

there's a big o-ring inside that could be stuck along with the gasket under the flange where the 4 bolts came out. Can you get penetrating oil spray in there to soak it?

That O ring makes it a tight, almost press fit. Even with a new soft oring it will go back in tight.

I just got done doing the same thing.What I did was to get it started was to use a pry bar between the housing and the flywheel housing.The other two gents are right, it the rubber seal that is holding you up.Going back in get it in as far as you can then use the 4 bolts to get the rubber seal poped in.

When going back in coat the seal with a little white Lubra-Plate & some on here have said they use greaseless hand soap but I never tried it. You don,t want to use any type like regular grease.Also not only put a coat on the seal but also the metal surface & lip it slides into.At the dealer shop we never used anything but the Lubra-Plate grease & for most other things where a little grease was required, even rod & main bearings but did coat them after putting on the grease with a coating of motor oil.

Go easy prying on the bolt flange and using the bolt to draw the flange in. They will break!!

Good advice OM too & also if the bell housing hole has rust or scale inside it take some sand paper & remove it & polish it bright. It should slip in fairly easy then as I have installed dozens of them & followed what I have suggested to you & they slipped right in with no problem.

Cheers guys for all the advice will try and get it
out at the weekend. Will let you know if I am successfull.

Got the pony motor clutch out with all your help. Am about to refit the cylinder liners and wondered if there was a specific dimension they need to
protrude above the cylinder block. I know the later cat engines should be a certain dimension but as I do not have a manual I am asking just to check before I put them in.

Thanks Andy.s

At the shop we would keep them at no less than .002" & max of about .005" or .006" Leave the seals off when you set them down in the bore to check the projection so they set down firm in the block & put a bar across each one & take a couple head bolts to draw the bar down tight against the liner to do the checking. They shouldn,t vary too much from each other on the projection.