Scored Bearing Insert
#1
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Year: 1999
Model: Cherokee
Engine: 4.0
Scored Bearing Insert
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!
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!
Last edited by BotakBeng; 11-20-2011 at 11:54 AM.
#3
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Year: 1995
Model: Grand Cherokee
Engine: 4.0 with all of the noise and clatter
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.
#4
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Year: 1999
Model: Cherokee
Engine: 4.0
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.
Total noob question....
Just a set of standard size bearing inserts from Napa?
Main Bearing Set (or the #7 would work)?
Thx again.
Last edited by BotakBeng; 11-20-2011 at 01:37 PM.
#5
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Year: 1995
Model: Grand Cherokee
Engine: 4.0 with all of the noise and clatter
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.
Last edited by Bustedback; 11-20-2011 at 04:38 PM.
#7
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Year: 1995
Model: Grand Cherokee
Engine: 4.0 with all of the noise and clatter
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.
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#9
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
#10
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Year: 1997
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Engine: 4.0L
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.
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.
#11
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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.
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.
#12
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
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.
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.
#13
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
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.
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.
#14
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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.
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.
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Year: 1997
Model: Cherokee
Engine: 4.0L
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.