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The sleeve that I made probably had a wall tickness .062-.090. I heated the sleeve in a heat treat oven and chilled the crank in a cooler of ice, pressed the sleeve on with maybe .001-.0015 interferance it's been 2 years. Then turned in a lathe between centers. Bearing material was some kind of t-6 aluminum , this material suggestion came from ACMOC post.

I took my block to a local Engine Re-builder today because of some concern with one cylinder. He is going to sleeve the one cylinder back to original specs of 1.750-1.751 so I can use the original pistons, which show no wear. The local cat dealer is the only place I could find oversize pistons and they were quite expensive. I can have the one cylinder sleeved and the other one honed for what two new pistons would have cost. The other cylinder only has about .002 wear and has already been sleeved, just needs honed. Rings were worn out so I can get new rings from Hastings. New rod bearings from Cat, Gaskets from Cat, Valves and Valve Guides, one new main bearing for the rear of the crank that I had already, and I will make a new main bearing on the lathe for the front of the crank, cut a new keyway for the flywheel and finish repairing the rear main bearing surface on the crankshaft, and I will have a new motor. Got started on the crankshaft today. Old Magnet, Looks like this press-on sleeve is going to work great. I got all the new parts and gaskets from Cat today, so things are starting to come together. Carburetor and magneto are in excellent shape so this thing should run like a top.

Besides, my wife thinks this ACMOC and restoring these old Cats is great. She doesn’t even object to what things cost, so when I get a bill she just says O.K. and sends the check. What more could I ask for?

SJ, Cleveland Bros. must be a great dealership. I see you refer to them quite frequently. I think this crankshaft repair job is going to work great with minimal cost. Just the other things that add up to $$$.

All sounds good...was fairly common to thin sleeve the cylinders.....I think you meant to say 2.750 on the bore. I'd still go with the lock tight on the bearing sleeve and the seal saver sleeve.

Hi bboaz & OldNuc,
After digging out a pony crank and looking it over closer it looks like I missed the
call on that one:rolleyes:
It does not have the surface texture nor the mating joint of typical cast items so I would conclude they are a drop forged piece......as susceptible to breakage as they are I had assumed and was told they were cast iron.
Could not find any info on these pancake pony motor cranks until I got to the D17000 which does state the crank is a dropped forged unit. Somebody please correct me if I am still wrong:)

Any time there is a question as to whether something is steel or cast iron, choose a place where a little grinder "nick" won' hurt anything. Touch the surface with a small clean grinding wheel and look at the sparks generated. Cast iron will have an orange colored spark whereas steel will have a brilliant yellow spark. Much can be told about the composition of the material tested by careful observation of sparks such as approximate carbon content, other alloys, etc.

Try this with a track grouser, a known cast iron part, a chunk of mild steel, a piece of high carbon steel and an old drill bit. You might be surprised at the difference in sparks (length, color, the way the sparks "split") each different material generates.

Right you are, Grump. There is a very good chart at:

www.ohiosteel.org/homepage/Spark%20Testi...Mystery%20Metals.pdf

It should be on everyone's shop wall.

I once bought a 'spark test kit' on ebay- small pieces of 15 different alloys to compare your mystery sample to.

CS

I made a press fit sleeve for both ends of the crank and also used the bearing mount to put them together with great results. Was able to turn the crank back to original size and use the standard bearings in the block. I made the sleeve on the flywheel end long enough to re-turn the taper for the flywheel and cut a new woodruff key seat. Had one cylinder bored and sleeved back to original size. The other cylinder had already been sleeved and was only .005 oversize. Honed it and left it alone. The pistons were in good shape. New rings, valves with new guides, and rod bearings later the motor is back together and running better than ever before. Starts the first time with only two wraps on the start rope

Thanks for everyone's input and recommendations. It has lead to another successful rebuild.

Brian Boaz

Bboaz, I had a crank for a D7-3T starting engine spray welded and turned to original size several years ago. I kept the tractor for 5 years and had no problems with it.

Bo, if a place that spray welds cranks knows what they,re doing you can,t beat it.At the Cat dealer we sent dozens of them to this local shop that ground cranks and other engine jobs and they would spray weld ours and we never had one problem with them and they held up good on the biggest diesel cranks that we had done. Cat did have an exchange program that you could get rebuilt cranks from them but don,t know if they have it anymore or not but I,d think they would.