The Stovebolt Site Forums The Shop Area Engine Shop Thrust bearings for a 235cui engine - thrust face

Hello,
I have another questions:
1. Does the thrust bearings from different companys have brighter thurst faces at the side of the bearings?
2. A undersize thrust bearing - 0,010 does it have brighter thurst faces than a standard thurst bearing?
Ask
Wolfgang

It will depend on who made the bearing. Bright or not, if the front to rear end play is right, it will work OK.
Jerry

Hello Jerry,
the crankshaft of my engine has a front to rear end play of 0,019685 and the other crankshaft which i bought has 0,01496063. My question is, is this end play to much for both crankshafts?

According to a service manual I have the end play for a 235 engine can vary from .007 inches to .009 inches. (0.178-0.228 MM)

It looks like you're slightly above the maximum end float on both crankshafts, but it's not likely to do a great deal of damage unless you're planning on hauling some heavy loads at high RPM. The rear thrust face (nearest the flywheel) is usually the one that wears due to pressure from the clutch release bearing. It is possible for a good engine machine shop to weld material onto the thrust face and regrind it to specifications, but in my opinion, you're not far enough out of limits to need that. Just use the crankshaft with the least amount of end float.
Jerry

Ok, I'll do it. But thats's the reason of my question, does different thrust bearings have different thrust faces which are larger/wide?

I don't know of any main bearings with over-thickness thrust faces. Some engines with separate thrust washers might have a thick washer that can be filed or sanded to fit, but I've never seen stovebolt main bearings like that.

One racing engine I ran needed a thick thrust face on a main bearing to salvage a very expensive crankshaft, so we fabricated a lathe fixture to be able to machine away the bearing material on one side of the thrust bearing and replace it with a built-up layer of silver solder, then machine it the right thickness to control the crankshaft thrust movement. Between making the machining fixture from a couple of discarded main bearing caps and doing the machining and welding, we probably had $500.00 worth of labor time involved. Of course, we also salvaged a $5,500.00 billet crankshaft that would have had to be discarded otherwise!
Jerry

When the machine shop ground my crank undersized, they included the weld build up and machining the thrust surface back to spec.

Kent Moore Chevy Thrust Bearing Facing Tool

Neat Tool!