Dead Main Bearings FTW!

[wild_maxx]

Some of you may have already seen my thread about the Clevite 77's in my last motor. They were considered normal wear for 1500 miles so I didn't really worry about it.

Today I decided to finish taking apart my motor (same one the clevite's ^^ came out of) and see how the main bearings and crank looked.

As soon as I removed the gurdle I saw where the problem was..... somehow the crank ate the main thrust bearins down to the copper. The crank is pretty scored as well where it was rubbing against the bearing. I asked a fellow mechanic what he thought about the bearings and he pointed out that they were only chewed up on the back side of the bearing. (transmission side) and the front side looked good.

He told me that the excessive pressure from the aftermarket clutch would cause this. The clutch pushes on the crank foward causing it to eat those bearings. I am running an RPS SS clutch.. nothing crazy.... anyone have any other ideas?

[NateDogg]

Could very well be possible. I've heard of it before on DSM and even a S2000 engine using a ACT Xtreme plate.

Are you using the MAX pressure plate from RPS?

[wild_maxx]

nope just using the standard stree/strip PP and disc from RPS.

[nissanfanatic]

Did you guys align the main girdle correctly?

[wild_maxx]

what do you mean by "align" the main gurdle correct?

[wild_maxx]

bump for some info.

[LEMHEAD16]

Did you check crankshaft end play when assembling the engine?

Did you "set the thrust" before putting final torque on the main studs/bolts?

[pr240sx]

I am completly clueless on what to check where and with what?

[wild_maxx]

I did check crank end play... I don't remember the exact measurement but I know it was within spec.

What exactly is "setting the thrust" before putting the final torque?

[LEMHEAD16]

Set the thrust - Use a dead blow mallet. After tightening the main bolts tight enough that the girdle is seated but before you apply final tourque. Hit the butt of the crank a few times (towards the front of the engine) and then hit the snout of the crank a few times (towards the back of the engine) this ensures that the two halves of the Thrust bearing are properly aligned. After final torque you should then check CS end play and adjust if neccesary.

This is the way I assembled hundreds of Toyota 22R-E and 3VZ-FE engines. When I worked for a machine shop.

Good luck. Make sure you have that thrust surfacce rechecked (and machined if Nec. ) Before reassembly.

[wild_maxx]

Thanx for the good info!

I won't be re-assembling this motor tho... i've given up on the SOHC motor after 3 dead motors and have decided to move over to the ka24de-t side with a fresh motor to work with.