BotakBeng

In the middle of replacing my RMS and these are my little problems....


It does look pretty bad.
What should i do? (Crankshaft looks fine....in my limited experience)

PO must screwed this up big time.....how do i remove the RTV?


Thanks in advance everyone!

BotakBeng

Here is another shot,


Appreciate all the help i can get.
Thx!

Bustedback

Replace the bearings since you have the pan off. You can carefully push them in without removing the crank, just loosen all of the main caps and the crank should drop enough to slide the upper bearing shell in. Make sure the saddles and the back of the bearings are dry when you install the bearing shells, you'll spin a bearing and destroy the crank if oil gets between the bearing and saddle. Once you're all done I bet you'll see an increase in oil pressure.

BotakBeng

Thx!
Total noob question....
Just a set of standard size bearing inserts from Napa?
Main Bearing Set (or the #7 would work)?

Thx again.

Bustedback

The old bearings should be stamped someplace on them, use the same size as the old ones. If you really want to go crazy you could do the rod bearings too. Make sure to use an accurate torque wrench and torque everything to spec. The NAPA kit is exactly what you need as long as they have the proper size.

BotakBeng

Thx!
I'll check the rest and if they look fine would it be ok to just replace the scored one?

Bustedback

No, do all of the mains. Doing just one could cause some problems if the crank were to flex because of one main being tighter than the others.

BotakBeng

Ok, i do all but not sure if i'm up for it.
Can seem to find any write-up.....appreciate if i can get some pointers.

Thx.

cruiser54

Post up your wet and dry compression numbers in this forum like you did on NAXJA.

Cherockee

Is the engine still in the vehicle? I assume it is... that would be uber-difficult to replace crank bearing while it's attached to the tranny, and do it right.

If you've spun the crank around and didn't see anything bad on it then I would just clean up that bearing and put it back in. Either that or pull the engine and do all the bearing the correct way.

Good luck though if you try to replace that bearing while it's attached to the trans- and take lots of pictures when you do it so you can show everyone.

Caish

That bearing is shot, just from the color.

Babbit bearings typically have a trio of metals and the last is copper so when you pull a cap and the bearing is mostly copper looking any place along it.
Its time to replace them.
Plus its cheap insurance and your there looking at it anyway.

cruiser54

Rolling main bearings into a 4.0 while it's still in the vehicle is a common practice. Doesn't matter that the trans is attached.

cruiser54

When the OP posted in a thread on NAXJA, I questioned him about the color. He said it was just the lighting and the color was actually silver. He also posted in the other thread that his compression readings across the board are 75 dry and 90 wet using multiple testers.

Caish

Those rings are SHOT.
You got the pan off, might as well pull the head and get a simple overhaul kit.
They're about $100 on ebay (cheapest I've found) for rings, rod bearings, and mains and gasket set) and refresh your worn parts.
It will be good for another 100k+ miles.

Cherockee

Rolling main bearing is an unreliable method no matter how common pratice it looks to be. I wouldn't trust any shop/mechanic that would recommend doing this, especially given the OP's experience in this matter.

With that low of compression this isn't going to be a simple sub-$100 kit to repair. The pistons are most certainly worn and the cylinder walls will need honed or possibly even bored.

I will however succum to the fact that you could throw a bunch of parts at this engine and it will keep running for another 20K miles, more of less. But if you want to drive this for anothe 100K take it out and rebuild/replace it.