Back in the mid 70's I worked for a large at the time automotive parts store/warehouse here. They sold remanufactured motors by a company named Lomac. It was very common to have new remanufactured motors by them that had 1 main journal or rod journal turned under sized or single hole bored over size & some time multiples in a single motor. We are talking on the order of 1 hole .30 or .40 over size & the rest std or maybe .10 over. The same with the journals. You could find any combinations. This was in all types & brands of motors. We sold a lot of them back then. Just sayn.
8ba rod bearing problem
- Thread starter 3739ford
- Start date
For the young guys... I worked in a small, independent shop in the 50's. At least where I was, it was VERY common to grind a crank in the car (or pickup). We had one customer that ran a small fleet of Chevy trucks for moving bee hives around. And, his drivers really pounded those old Chevy's. So, they had rod failures quite often. The guy that did our 'in-truck' rod journal grinding had a steady customer at our shop. And, some of the under-sizes would be un-heard of today. Like one I remember as .090 ! The guy that did the grinding also provided the bearings, or in the case of Chevy's, the babbited rod. So I never knew how those odd-size bearings came about.
I think the current-day generation that tries to make precision in old engines would likely never understand 'how-it-was'. After all, they're just old Fords, Chevy's, Plymouths, etc, etc. JMHO
Kohnke Rebabbitting
Well-known member
It would be a long explanation to describe how it was done. First the grinding is done with the end face of the rock. The electric tool has a long snout to provide clearance for crankshaft counterweights. There are 2 types of drive systems for rotating the crankshaft during the regrind. One is a set of motorized rollers for a rear(drive) wheel and the other is a starter replacement driving system for automatic transmission cars. The operator must find areas of the journal which are "round" usually involving some hand filing and sanding to accomplish. Even a badly galled or spalled journal will have small areas outside of the rod contact area to use. There is a hinged/jointed device, like a claw, attached to the grinder motor which over reaches the journal and provides the support and a guide for keeping it round. There are more details but this might give you some idea.
Obviously small cuts are the norm but it actually worked reasonably well.
Obviously small cuts are the norm but it actually worked reasonably well.
cadillac512
Well-known member
There 'ya go...that's a good deal now. That rod would have given you trouble too,and possibly a LOT of trouble. Well done for questioning things the way you did!
Terry
Terry
