Bearing condition

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Not sure what your asking? But if you want to know if you can reuse them, I say no way! Bearings look like they came out of a high mileage engine? Also looks like quite a bit of grit has eaten away at them. Crank needs checked and at a minimum polished.
 
I'm the furthest thing from the authority on this but I'll jump in to get things started.
They look very scored to me. I'd guess the crank will need to be turned.

Nothing wrong with pulling an engine with limited knowledge. It's what you do next that matters :)

Give us the story on the engine.

edit: I guess I was 2nd to jump in.
 
Engine is a 340 that was supposedly a fresh rebuild when I bought the car. I have had the car a year and put 3500 miles on it. Have been chasing a noise that comes when warmed up, sounded almost like a lifter or exhaust leak at first but had gotten worse. Still is only there when warmed up. Replaced all lifters, push rods, and rockers, no change... Bearings have been in the back of my mind since I discovered he had put an external balance converter on a neutral balanced motor. Car was driven about 1500 miles before I discovered it. Have been working backwards on the car fixing all the half *** stuff that the previous owner did.
 
Bearings are shot. Kinda looks like the one got hot. Don't buy new ones until you get the crank checked out, just in case it needs to be turned down. And while you're at it look at the rod journals, you may as well replace those bearings while you're at it.
 
First photos are of the main bearings and the last five or so are of the rod bearings. Bearings are Clevite 77 .010 I kinda figured they were bad, didn't think you should see the copper. Hoping the crank OK. The crank is actually still very smooth , no ridges or gouges and does not appear to have the over heat look like some of the bearings do. Not saying I'm not going to have it check out, just hoping I can reuse it.
 
If you run your fingernail over it and it don't have a major catch, that's a good sign, not scientific I know. You just may be able to get away with a polish. Those bearings remind me of the 318 I did about 30 years ago. One looked real bad, but I was able to get away with a polish only.
 
Looking at the picture that shows the crank journal - that is not usable in that shape. looks like a LOT of dirt went in that. Perhaps not cleaned well prior to assembly or lots of running int eh desert with a cheapo air/oil filters? I would not run them that way, and I'd plan to have the crank looked at by a competent shop. It may only need polishing but it looks fairly scored.
 
Going to do it right. Going to tear it down and go through the whole thing and make sure everything is good.
 
By the look of the variance in the copper vs babbit, the crank needs turned.
I have seen stock SBM motors with over 100K with bearings that look better than that.
Also I would pay to have it balanced, something is way off in that combo.
 
I can't see the pics but whenever I get an engine down to the point where I have the bearings, the bearings get replaced even if they still look ok,
 
1968FormulaS340 said:
I can't see the pics but whenever I get an engine down to the point where I have the bearings, the bearings get replaced even if they still look ok,
Click to expand...

Since you cant see the pic's I will tell you what I see.
It is bad.
Bearings in copper, shot.
Crank has lots of grooves in it.

Minimum machine work required: crank turn, rods resized, balance.
 
Well, got it disassembled today. No new problems but the crank does worry me. Will get it to a shop next week. Curious on the numbers on the engine.

Drivers side cast is 2780930-340-8

passenger side at oil pan lip is B209385

Drivers front just below cylinder head is HM 340R 37450054
 
If its not the forged crank, its not a real high dollar item if you have to replace it.
 
Forged :sad7:

Do I have to replace it with the same or can I go cast?
 
I think forged would be optional. Likely it can be turned or polished.
 
dgibby said:
Curious on the numbers on the engine.

Drivers side cast is 2780930-340-8

passenger side at oil pan lip is B209385

Drivers front just below cylinder head is HM 340R 37450054
Click to expand...

I'll give it a shot.....

HM 340R 37450054
"H" = Built for 1972 model year
"M" = Mound Road assembly plant
"340" = 340 Cu In.
"R" = Built for regular fuel
"3745" = Assembled on Fri, Oct 29, 1971
"0054" = the 54th unit built that day


B209385
"B" = Car assembled at Hamtramck, Mi.
"209385" = Last six digits of the vehicle (vin#) it was in stalled in


The Forged crank corresponds with that build date if you believe Chrysler's bulletin that went out stating the Cast units started on Apr 11, 1972.
View attachment 340 bulletin.jpg


If i'm mistaken somewhere, i'm sure a more knowledgeable member will correct me.
 
Looks to me like you could get away with a good polish on that crank.
 
OldmanRick said:
I'll give it a shot.....

HM 340R 37450054
"H" = Built for 1972 model year
"M" = Mound Road assembly plant
"340" = 340 Cu In.
"R" = Built for regular fuel
"3745" = Assembled on Fri, Oct 29, 1971
"0054" = the 54th unit built that day


B209385
"B" = Car assembled at Hamtramck, Mi.
"209385" = Last six digits of the vehicle (vin#) it was in stalled in






The Forged crank corresponds with that build date if you believe Chrysler's bulletin that went out stating the Cast units started on Apr 11, 1972.
View attachment 1714664800


If i'm mistaken somewhere, i'm sure a more knowledgeable member will correct me.
Click to expand...


Wow! Great info, Thanks!
 
Well, looks like it will live... crank can be turned! Going set me back $110.00 bucks, not too bad, could have been alot worse if I didnt catch it.
Going to have him hot tank and hone the block while he has it and balance it also. Will be nice to know that its been done right.
 
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