What is a thrust bearing and how do you tell if it's bad?

[kna4977]

At this point i would remove the number #2 main cap and inspect the thrust bearing. Shavings are bad. You need to find the cause off the shavings. The low rpm knock could be piston slap and not a rod knock. Rod knocks usually get worse with more rpm.

All the cylinder walls look great, so I don't anticipate a piston slap, but I may be wrong. It definately goes away even if you breathe on the throttle to make it different from idle at 750-800 rpms, so it is when the vehicle is at idle, so it's probably not a rod.

There were a few (3 or 4) gold color shavings on the inner surface of the oil pan. There were also a few on the oil pump screen. I don't see a localized source for the shavings. Everything looks tight and I'm not really able to move anything. I can move the connecting rods very slightly back and forth on the crank. They all move the same distance so I assume this is normal. I am not able to move the crank at all, but then again, I don't know under what conditions I am supposed to be able to make it move (what I'm supposed to disconnect to allow it to move). If I remove the #2 main cap, what should I torque it back to upon reinstallation?

 

[bison]

Factory bolts=100 ft/lbs
ARP studs=usually 95 ft lbs
Piston slap is from a little excess clearance on the piston to wall. Wont scratch or wear out the pistons or walls, just be a little noisey at low rpm. Almost every engine ive had in the last 8 years had a little piston slap cold.

 

[kna4977]

Factory bolts=100 ft/lbs
ARP studs=usually 95 ft lbs
Piston slap is from a little excess clearance on the piston to wall. Wont scratch or wear out the pistons or walls, just be a little noisey at low rpm. Almost every engine ive had in the last 8 years had a little piston slap cold.

This happens when warm at low idle. The surface of the thrust bearing looks good