Quote:
Originally Posted by Alex van de Wetering
Mike; do you mean the radius of the bearings is bigger than the radius of the caps? I guess that's a good thing....as it clamps itself inside the cap, rather than around the crank, right? (wishfull thinking maybe  )
Did you use the NASCO bearings for your C8 at the time?
Lynn; thanks again for your ideas. Maybe, getting a proper newly made bearing kit is indeed the way to go, but I have some leads, one of them a very good offer from Mike, so I want to see if this could be the solution for my engine.
But I agree...with so many wrong descriptions of NOS bearings sets around, it could be wise to spend some extra cash on a set from one of the Chev parts dealers in the US instead.
Talking about oval shaped bearings......Do two bearings shells clamped together by the caps from a perfect circle?......or an oval, with shims needing to be added to get the result to be a perfect circle?
Alex |
My C8 has the original babbit lined rod bearings, I removed a few shims from each cap and it's been fine. I polished the journals before re-assembly with a fine emery cloth .
A good engine machinist will fit the new bearings in the caps , then he bolts the bearing caps down and tightens to the torque specification ( no crankshaft in place ) , then he measures the bore of the bearing with a accurate gauge . The measurement tells him what size to grind the crank to , normally they allow about .001"per inch of diameter for clearance . eg for a 3"diameter journal, they aim for a .003"clearance
Measuring the bearing bores after the caps have been tightened down ( no crankshaft in ) is very important . I think a slight oval is acceptable.
I think Lynn explained the crush concept well. Anyway I hope the NASCO bearings fit .