The Stovebolt Site Forums The Shop Area Engine Shop Can't Remember Bearings Or Babbitt's

Does a 1953 Chevy 3600 pickup with a 216 engine have Bearing inserts or are there Babbitt's. Thanks!!!!!!

Marv.

I think that no 216 engines originally came from the factory with insert rod-bearings?

I think that the 1953 Powerglide car 235s (and that year's Corvette 235s) had factory-equipment insert rod bearings?

Tim is correct!

All the 216's that I'm aware of had Babbit-lined connecting rods. There is a conversion bearing available that involves boring the Babbit rod out to fit the bearing, but some sizes of them are getting very scarce and expensive. A possible work-around is a rod bearing for a 3-cylinder Perkins Diesel engine. The rod is bored to fit the bearing, and the crankshaft is ground to fit its inside diameter. One advantage to that procedure is that a "worn out" .030" undersize 216 crankshaft can be reground another .030" to fit the standard size Perkins bearing. The crankshaft doesn't really care what size it is, as long as the oil clearance for the bearing is right. NASCAR engines run 8K+ RPM with a rod journal size of only 1.850"!
Jerry

All 1954 and later 235 engines, and, all 261 engines (introduced in 1954) had insert bearings.

Just to add a little something to Jerry’s post, if your 216 has been rebuilt in the past it May have insert bearings installed.

I have discovered when machining rods for insert bearings that the Babbit used by GM in OEM connecting rods is extremely tough stuff. It can dull a high speed steel cutting bit with just a couple of passes. Rods reconditioned by aftermarket suppliers usually have much softer bearing metal than GM used originally. I've started using nothing but tungsten carbide cutters in my micrometer boring head for roughing out the rod bores, then finishing the diameter with a Sunnen hone.
Jerry

Jerrry, you do know that you can melt the babbit out without affecting the temper of the rods, right?
I know this because I've melted out a few on Model A rods (one going down the road when it was adjusted too tight).
You only need to get it up to around 600F. Easily done even with a propane torch.

Yes, I've done it that way also, but since a little of the rod also has to be bored to fit the insert bearings, it's simpler to get a true center with a last word dial indicator with the Babbit still in place. There's only a few thoudandths' worth of tolerance before the cutter starts getting into the rod bolts when boring for insert bearings.
Jerry

Ah! I understand now. Is the steel bore of the rod not concentric with the babbit?

"Close, but no seegar"- - - - -The original method of applying the bearing material was a process called "centrifugal casting". The rod was heated to close to the melting point of the bearing material, and molten Babbit metal was sprayed on while the rod was spinning in a rotating fixture. Then it was honed to size. Reconditioned rods were usually tinned, and the bearing material was poured into place, them machined/honed to whatever final diameter was desired. The centri-cast OEM rods have a MUCH harder bearing alloy than most recon rods. Once I machine most of the soft metal away, sometimes it's necessary to adjust my rod-holding fixture to get a true center so the big end hole is located exactly between the rod bolts. The last few thousandths gets honed out so the hole is round, centered, and the bearing gets the right "crush" to hold it firmly in place.
Jerry