VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 1931 pilot bearing

I discovered my 31 engine does not have the crankshaft that will accept the ball bearing but one that is machined for a bush. My guess is someone once replaced the crank with a 1930 that came with the bush. Two questions, will the 30 bush work with the 31 main gear tranny shaft? Will the earlier crank be acceptable in the 31 motor?

Thanks

You should not have any problems with the '30 crank in a '31 block. The bushing is compatible with the transmission input shaft and many think a better option than the sealed bearing.

thanks!

The pilot bushing from the Filling Station arrived, fits the crank but is loose on the main drive gear. The NDH bearing fits well on the gear. Looks like when they changed drive gear part numbers one of the changes was the size of the end of the shaft.I will have to try and find one that works.

The transmission input shaft diameter and splines is the same from the 20s through the 80s, maybe later. The bushing ID may be a little loose. It should tighten a bit when pushed into the crank.

That is good to know. I did some measuring, the new bushing has a id of .625, the NDH bearing has an id of .590 and the shaft end measures .589. I wonder if the bushing will compress that much or if it has been made out of spec?

Don't know the answer to either question. I suggest you talk to Steve at The Filling Station and let him know your concerns.

Steve from The Filling Station here. The ID of the bushing for 1930 is not the same as the ID of the bearing used in 1931. If you have a 1930 crankshaft in a 1931 engine, you have a big problem. The input shaft OD is larger on 1930 than in 1931 and newer engines. The bushing will fit the crankshaft fine but will be too large for the 1931 input shaft. The only solution I can think of is to change the input shaft to a 1929 or 1930 shaft OR have a custom made bushing to give you a proper fit. 1929-1930 Bushing ID: .625" 1931-1938 Bearing ID: .590"

Steve, thanks for the info