Rear Main Bearing

[kboldin]

Was replacing the rear main seal today and found this..... So how bad is it? I mean, can I still run it the way it is or do I need to replace the bearings i.e. "time for a rebuild"?

http://i325.photobucket.com/albums/k378/kboldin/rear_main_2.jpg
http://i325.photobucket.com/albums/k378/kboldin/rear_main_1.jpg

 

[thesameguy]

Wow, that's not good. Frankly I'd decide what you want from this motor, and either take it down now or drive it til there's a real problem.

 

[rbohm]

8) i would say it is close to time for a rebuild. you are getting down to the copper backing on that bearing, which means fairly large bearing clearances. i would go for freshening up the engine soon before you have issues.

 

[kboldin]

Thanks fellas, I think I've been had a bit. The car is in excellent condition with a purported 68k actual miles. It looks like it but the motor is telling me a different story..... So disappointing..... I think its going back together as is and I'll source another 200ci for a rebuild project.

 

[bmbm40]

That is a good plan, you can keep driving while you build your new motor, no down time. I got a good deal on another six for my Bronco a while back and was glad to get it because the sixes will get harder to find.

 

[69.5Mav]

So how bad is it?

You can replace that bearing in the car, I would. That is the end bearing and it takes the most pounding. If the rest of the engine is in good shape it could last a good long time giving you a lot of time to find and rebuild a replacement on your schedule not its.

Bearings are cheap. If the Journal is in good shape you could give it a try. You might have to buy more then one set to get the clearence correct. I did when I replaced the rod bearings in my 82 Sentra. 20K miles later it still runs fine. It went from rod knock to no rod knock.

 

[kboldin]

Both are not bad plans, I definitely want it on my schedule. I may try a little plastigauge just to see where the clearance is. If I can find another engine on the cheap, I think I'll just roll it as is, baby it where I can and do a steady rebuild.

 

[kboldin]

So I contacted the PO to see if they had any further information and they said that the damage was consistant with "lack of use". What do you all make of that?

 

[thesameguy]

I would make a noise that sounds like, "Whaaaaaaa?"

 

[rbohm]

So I contacted the PO to see if they had any further information and they said that the damage was consistant with "lack of use". What do you all make of that?

8) i can see that since it is in a small area, and without consistent use the bearings would always dry start.

 

[kboldin]

"That spot on the bearing looks to me like the engine sat for years with the bearing at that one spot and moisture somehow accumulated at that spot (the oiling hole in the crank looks to be a near perfect match to it) , it looks like corrosion, not wear."

Does this sound plausible?

 

[69.5Mav]

moisture somehow accumulated at that spot

Does this sound plausible?

Yes. When I saw that it looked a lot like the rod bearing I pulled from my 82 sentra.

Water is heavier then oil so it would tend to settle and collect at the lowest spot.

Replace the bearing if the journles look good and check the rest including the rod bearings and you should be fine.

Fact is it might be a good idea to check the bearing on all used engines before instalation for just this reason.