The Stovebolt Site Forums The Shop Area Engine Shop 40-60K bearing adjustment

I know that was accepted norm with a 216, but with "full pressure" 235 wasn't that pretty much eliminated? Lotsa full pressure folks eventually change insert bearings without removing crank, but the need for that wouldn't arise for how many miles (assuming frequent oil changes)?

I ran mine about 200,000 before I changed the bearings in-frame. 55 2nd 235. It always had a filter and mostly highway miles.

A Cummins Diesel field trainer was teaching a seminar on engine maintenance to a bunch of yacht owners at a marina where I used to do a lot of electrical repairs. When somebody asked him how long a Cummins engine would last, he replied "Long enough to eat 10 pounds of dirt!". He was emphasizing that regular oil and air filter changes have a huge impact on engine life. 10 weeks- - - -or 10 years- - - -or 50 years- - - -it all depends on how clean the owner keeps the engine.

Adjusting Babbit bearings with shim stock was a routine job, usually done during a "ring and valve job". The piston rings in the 40s and 50s were the weak point, and they usually failed long before the rod and main bearings did. Precision insert bearings can't be shim-adjusted (or at least it shouldn't be attempted), so keeping the oil clean and dust out of the intake will be the determining factor for bearing life on engines since the mid-1950s.
Jerry