Allis d262 diesel motor help required

seanranger

New User
I am currently restoring a allis dd grader fitted with the d262 diesel motor, i have comprehensively rebuilt the motor and when test running
the motor before refitting it i noticed it has a loud heavy knock, i have dismantled it twice now to locate the problem but no signs of any
faults?

Has had full rebuild kit, pistons, liners, crank grind and matched big end shells, fuel pump and injector rebuild, head overhaul with new
valves.

starts easily and has 35 psi oil pressure.

Any help would be much appreciated, thanks.
 
This job is definitely turning into a worldwide effort, didnt replace the small end bushes as originals were ok and a nice fit on the new piston pins. No scoring etc.

thanks
 
I agree the sound seems to match what you have said, cant see any evidence on the last couple of times i pulled the motor down, top of pistons still seem unmarked. I have heard there are a couple of different pistons but have been unable to find out the exact difference as yet.

cheers
 
The ledge the sleeves sit on it the block are notorious for rusting and the sleeve then drops in the block. Allis used to sell sleeves with a thicker flange on them and a cutter to recut the counter bores. Nobody makes the thicker sleeves anymore so now you have your machinist recut the bores square again and then surface cut the block to end up with the correct sleeve stand out. This can be a problem over the years. I overhauled a 262 in a D17 because the head gasket started leaking and the sleeves dropped. I also found the block had been cut enough that the pistons were hitting the head. Before I took it apart it always had a very distinct diesel knock and did start very well. Having the pistons hitting the head was giving a little boost in compression.
What I measured at teardown was a compressed head gasket measured .045, the piston protrusion varied between .050 and .060 above the deck. All of the small bushes in the rods had a groove in them too.
 
Thanks for your response, that has been very useful, i assume the d17 is the tractor which uses the same motor and the same specs will apply. I believe my engine to be a bit of a assortment of parts thrown together over the years, i believe it could have a d230 head as the water pump is held in place with a single bolt through the centre.

cheers.
 
I am ivor from uk
I don't suppose it is helpful now but there is a firm in uk that manufacture liners and there is no minimum order
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top