My latest... Thrust Bearing

[mtocrs1]

Check this out. Decided to replace the rear main seal. While I was in there I pulled on on the crank to check the thrust play. Clunk! WTF I thought. Pulled the thrust cap and found this.

Wear on both thrust surfaces. Journal area looks fine IMO.
I can see hash marks on the crank thrust surface and it feels to rough.
Can I polish the thrust surface myself at home somehow?


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[mtocrs1]

Forgot to add that I measure the thrust play and had .007. Way to much. What is the spec?


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[bison]

.007 isn't too much. What does the crank thrust look like


BPE2013@hotmail.com

 

[mtocrs1]

I'll have to grab a pic. Looks good. But it looks like cylinder wall with croshatches.


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[Steve V]

.003-.011 is the spec.

 

[mtocrs1]

Here are some crank pics

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[Steve V]

Put it back together nothing is wrong.

 

[mtocrs1]

Put it back together nothing is wrong.

You sure about that? I don't think you should be able to see the brass color on any bearing. Maybe I'm wrong. Hopefully some others will chime in and confirm.


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[bogies87]

Did you have the crank turned? Its possible the machine shop got into the thrust and the roughness is just that. I have heard of being able to polish the thrust surfaces. Also did you plasti gauge the caps prior to installing? If the other bearings dont have copper on them, then either the clearances are screwed up or you have some serious crank flex...

 

[mtocrs1]

I didn't assemble or build it. I bought it as a running engine. Swapping cam, heads and was just installing the rear main.


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[Steve V]

You sure about that? I don't think you should be able to see the brass color on any bearing. Maybe I'm wrong. Hopefully some others will chime in and confirm.


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Yep...Some thrust bearing surfaces are copper out of the box. I will look tonite at a few sets and snap a pic. I believe it clevite.

 

[mtocrs1]

Yep...Some thrust bearing surfaces are copper out of the box. I will look tonite at a few sets and snap a pic. I believe it clevite.

I have seen some of those bearings. I don't think it is the same material on those. But I'm no expert. I will say that on mine, even though the copper color is through nothing looks chewed up at all. Everything is nice and smooth.


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[Chuck Leeper]

It's had considerable dirt thru it...........

 

[mtocrs1]

It's had considerable dirt thru it...........

How did you come to that conclusion?


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[m233roller]

Hate to say it but I'd be alot more worried about the bearing crank surface than I would be about the thrust surface.

 

[mtocrs1]

Hate to say it but I'd be alot more worried about the bearing crank surface than I would be about the thrust surface.

Care to elaborate? Looks pretty good to me.....


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[m233roller]

Sorry, I meant the bearing it's self. The thrust sides of the bearing don't look that bad but the copper showing on the bearing isn't good. Crank looks ok.

 

[BMR]

I just got through assembling my 3.8 this weekend. I used Clevite bearings and the thrust area was copper straight out of the box.

 

[ek02]

It could be that the trust surface on the crank was ground and an ovesize bearing was used. I would replace the mains and double check that the bearings are not oversize on the thrust surface. There should be some markings on the back of the shell. The crank end play is .004-.008. If you were at .007, it should be fine with new bearings. If the bearings are Clevite, they may be OK to reuse.

 

[m233roller]

Yup most are copper on the sides but that's not what I'm trying to get across here. If that bearing is into copper on the surface that mates to the crank journal. You've got problems, Period !!
Measure,measure and measure again.