Engine torn down-crank bearing color

[85GT_Project]

Hi all,
I just finished tearing my engine apart today (85 302, 100k miles). The crank bearings have me a bit worried. I am attaching a picture so you can see the discoloration. I thought I heard/read somewhere that the copperish color was a bad thing...

 

[1986LX2002]

yeah time for new bearings! Those are trashed, i'd go with some clevite bearings.

 

[Nosfurato]

Hi all,
I just finished tearing my engine apart today (85 302, 100k miles). The crank bearings have me a bit worried. I am attaching a picture so you can see the discoloration. I thought I heard/read somewhere that the copperish color was a bad thing...

Dude, how often is the oil changed in that motor?? it sure doesnt look good.

 

[battyice]

I can't really tell if it is the way your picture was taken or if the copper really only showing on one side of the bearing. If this is the case, you should have your crankshaft checked for straightness by a machine shop.

-Other than that, no need to be worred about copper showing after 100k, I've seen bearings from a 302 with 80k that were worn far worse than yours. Have your crank checked out by a shop, polished/turned, and get yourself a rebuild kit.

Just out of curiousity, why did you tear your motor down to begin with?

 

[Rick 91GT]

I can't really tell if it is the way your picture was taken or if the copper really only showing on one side of the bearing. If this is the case, you should have your crankshaft checked for straightness by a machine shop.

-Other than that, no need to be worred about copper showing after 100k, I've seen bearings from a 302 with 80k that were worn far worse than yours. Have your crank checked out by a shop, polished/turned, and get yourself a rebuild kit.

Just out of curiousity, why did you tear your motor down to begin with?

I agree if it is just the side it could mean a few things, main alignment, crank, etc... I would have the block tanked and checked, and if the bores are OK just hone and re-ring it. Have the crank checked, polished and but all new bearings in the motor and put it back together.

Now if you plan to race it hard it is time to make some decisons while it is all apart...

 

[85GT_Project]

Dude, how often is the oil changed in that motor?? it sure doesnt look good.

I bought the car a couple weeks ago for $750 as a project car. I REALLY wanted a late 60s stang but figured I needed to practice first. I drove it for a total of 3 hours over a two week period and started tearing it apart. As far as history goes, I have no idea....hence the complete tear down.

C

 

[jd351]

Copper showing through at those miles is typical- lucky it's not down tho the base (steel) material. The crank should be polished B4 you re-assemble anyway, but a re-grind and line honing the mains would be best. As they were worn on one side only, this is a sure sign of mis-aligned mains, again typical of production machine work+age. The block will move a lot with heat cycles, but if you fix it now it should stay good for the life of the block.

IF (Big IF) you choose not to have the block align honed/bored, I would use a Babbit/Copper alloy bearing like a Child&Albert race bearing as they will conform much better and do not have a steel shell to damage the crank.

 

[85GT_Project]

I agree if it is just the side it could mean a few things, main alignment, crank, etc... I would have the block tanked and checked, and if the bores are OK just hone and re-ring it. Have the crank checked, polished and but all new bearings in the motor and put it back together.

Now if you plan to race it hard it is time to make some decisons while it is all apart...

I don't plan on racing it but I do want a healthy engine that can withstand an occasional romping or two. I would like to keep it mostly stock (well, partly)...was thinking of new pistons, maybe an overbore....there are so many possibilities! I am new at this so it is going to take me some time to figure out what all I want to do.

BTW, do you need special tools to get those bearings out?

 

[85GT_Project]

I should note that the engine seemed to be fairly strong before I tore it apart. Like I said, it had 100k miles and this is a "fun" project car so what the heck...tear it apart. maybe add some enhancements.


C

 

[Nosfurato]

I bought the car a couple weeks ago for $750 as a project car. I REALLY wanted a late 60s stang but figured I needed to practice first. I drove it for a total of 3 hours over a two week period and started tearing it apart. As far as history goes, I have no idea....hence the complete tear down.

C

Ok, for 750 bones, I guess thats not too bad of a deal.

At any rate,.. that kind of wear does suprise me if the car only has 100k on it. Given the odometers on stangs that old, it could possibly have 200k on it. Wich would explain the wear on the bearings.

Heck, I have a 1990 LX 5.0 with 24x,000 on it.. thats right, 240k original motor. Still runs great. no noise at all.

Given the age of the car, looking at the pictures, i'd say its prolly a 200k motor, maybe even more. who knows. But hey, for 750 bones. who's complaining?

Get her up and runin again, we need a few more "four eyes" on the road!!

Will.

 

[Rick 91GT]

I've seen bearings that like that after 5000 miles, I would not be too worried about it.