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Posted By: AZScott Case Bearings Question G80s - 05/10/19 3:00 pm
Getting ready to install my two crank bearing on a 1955 G80s. I have read differing opinions on how to attack this, bearing on shaft first, and bearing in case first. I have always done it by heating the case first and dropping the cold bearing in. My bearings are new British bearing that are a tight to the shaft. My plan was the heat the case first and freeze the bearings, then drop both bearings in the case (with spacer between). Then heat the case and bearings, and push the crank shaft in. Seems logical but thought I would ask the forum for advice since this is the first time I have installed two bearing on the same side of the case.
Posted By: Rohan Re: Case Bearings Question G80s - 05/13/19 9:18 pm
Usually when these engines come apart the bearings stay on the shaft.
Hopefully, and they haven't been spinning on the shaft....

If your new bearings are a tight fit on the shaft, I think I'd prefer to assemble them that way too
- that way you can be sure the bearings are the correct spacing from each other, and if they are tough
to get on then you can work on them - you don't want that while trying to poke the shaft through
them if the bearings are already in the case.

With the bearings on the shaft, you can heat the cases and slide the whole lot home.
Isn't the saying if you spit on the cases and they spit back then they are hot enough.
This should make them a slip-on fit.
Posted By: AZScott Re: Case Bearings Question G80s - 05/14/19 3:54 am
Thanks Rohan, When I pulled the case apart the bearings were loose on the shaft and the separating spacer was damaged and in two pieces. I like your advise on first putting the bearings on the shaft first, then heating the the casing.
Thanks again for taking the time to answer this post.
Posted By: Rickman Re: Case Bearings Question G80s - 05/14/19 1:44 pm
Also in this scenario, you could freeze the crank and bearing assembly, once you've cleared enough space in the freezer, a whole day ahead of the fitting into the cases...
Posted By: AZScott Re: Case Bearings Question G80s - 05/14/19 8:23 pm
Thanks Rickman. That's exactly what I did. It all went together a couple of hours with no problems.
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