I called CAT and they have upper rod bearings for the pony motor but the lower have been discontinued.
these are two halves of the same bearing and they appear identical to me. Did CAT discontinue the lowers because the upper and lowers are the same?

Sincerely,
Jason Phelps

See if you can tell if the bearing that Cat sells has an oil hole in it. On some older aircraft engines, the early parts book listed two different bearings for (in my case, the cam) upper and lower. To reduce cost and avoid putting the lower bearing which didnt have an oil hole in the upper position, they just started selling both half with the oil hole. Only one part number. Maybe Cat has done that. An un-needed oil hole in the half of shell that goes into the rod cap wont hurt anything. A young parts counter guy might not have ever run into that before. This is just a possibility that might be worth checking out.

The standar lower bearing is 4b7464 and the standar upper bearing is 4b7463 and should be different

Hi team,
i stand to be corrected but I seem to recall that the box you order has 2 shells in it these days and I seem to recall, as said above, both are now the same and have the oil hole as it does not affect the lower bearing operation but certainly affects the upper if incorrectly installed--The Dealer NPR should have given a publication reference that would tell of any possible changes--if applicable.
Maybe check with The Dealer and see if this is so or if there are two shells in the box.
Cheers,
Eddie B.

"edb" wrote:

Hi team,
i stand to be corrected but I seem to recall that the box you order has 2 shells in it these days and I seem to recall, as said above, both are now the same and have the oil hole as it does not affect the lower bearing operation but certainly affects the upper if incorrectly installed--The Dealer NPR should have given a publication reference that would tell of any possible changes--if applicable.
Maybe check with The Dealer and see if this is so or if there are two shells in the box.
Cheers,
Eddie B.

Thank you very much! Do you think it could be the same with the main crankshaft bearings? 3B8276 has been discontinued but 3B8277 is still in stock.

Sincerely,
Jason