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Discussion Starter #1
To sum up my summer... Blown motor this spring, bought a running 302 for $250, installed it, got my exhaust done, fired it up to find that the bearings are shot. just scraped up the money to get it fixed, and today I got the motor all prepped up so that on Monday or Tuesday I will pull it.

When I got under the car to unbolt the flexplate from the T.C. I found that the flexplate is extremely loose. Would that be the noise that I hear when the motor is running? I mean, I know that it shouldn't wiggle in there AT ALL.

I will lift the motor on Monday to change the flexplate bolts. Some people say use teflon sealant on those bolts. Is that necessary?

The guy that sold me the motor heard it run and immediately refunded me the money. I guess that I will have to give it back to him if this is all it is!

Maybe this car will see the road soon!
 

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Just some guy
67 coupe, 69 Sportsroof, 86 hatchback
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When I bought my car it had a flexplate that was cracked and actually broken. This made such a horrible noise the seller was under the impression that the rods were about to come out of the engine. It did indeed sound that way. I replaced the flexplate. The expression on his face as I drove past him in the car 3 days after buying it was priceless. A friend of mine bought a Camaro a couple of years ago with "bad rods". He discovered loose flexplate bolts and one actually gone. Replaced them and the "bad rods" were fixed.
If you are replacing/tightening the bolts that hold the flexplate to the crankshaft, yes use a sealer. I like to use thread sealer, other folks use blue Loctite. Either works fine but in your case you might prefer Loctite as the bolts have "loosened" on you once already.
Let us know how it works out!
 

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I had the same problem, and it was the flexplate bolts hitting the spacer plate. Worked out for me 'cause I took the auto out and replaced it with a 3-speed that supposedly was original equipment. Bob
 

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Discussion Starter #4
So then I guess I might be on the right track. Good to know! I will lift the motor, change flexplate and bolts, and fire it up again to see if this is my problem. Even if it is not, it is certainly worth the $$ to find out... better than having a machinist tear it all down!

Sounds like it might be the problem! Thanks!
 

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Just some guy
67 coupe, 69 Sportsroof, 86 hatchback
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No guarantee, but it sure does happen. I'll be keeping fingers crossed for you. ;)
 

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Once you have the motor out, it wouldn't take much to pull the pan and look at the bearings. Sure would beat having to pull it again. Plus, you would then know what kind of condition the crank and bearings are in. Anyway, that's what I'd do.
 

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Discussion Starter #8
Since I don't know jack about bottom ends, (they, like trannies and serious electrical stuff scare me), I have absolutely no idea what I am looking for in the bearing issues.

I know that the main bearings will be all but invisible (covered by the caps). The rod bearings are visible, but are covered by the bottom end of the rod. What am exactly am I looking for?

Metal shavings in the pan?

I would like to at some point switch to a high volume oil pan in the 7-8 quart range for additional cooling. (cool looks too) I guess now would be the time for that....

Thanks guys and gals...
 

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Used bearing inserts should look kind of silvery gray on the surface. If they are showing different layers of wear, or bronze is showing through, the coating of bearing material is worn off. Scored surfaces on bearings or the crankshaft surfaces (journals) they run on are signs of problems that will require crankshaft removal and regrinding. The use of plastigage will also show any excessive wear.

If there is some excessive wear showing on the bearing surfaces, but the crankshaft journals are smooth, you can prelube and "roll" new bearings in, as Lemondrop suggested. This is pretty easy, and just takes a minimal amount of time, effort, knowledge, and expenditure. The size of inserts will be marked on the back of the insert shell. You must replace the old ones with new inserts of the same size. The only tool you need to do all of this, outside of very basic wrenches & sockets, is a torque wrench. Care must be taken to replace all rod and main caps in the same place they came off of, and the same orientation. They should be marked prior to removal. I use a centerpunch to do this, making very small identifying marks on the bearing cap, and the corresponding rod. That way you will easily be able to put them back on the proper rod. Same thing for the main caps. If the crankshaft journals are in good shape, a new set of bearings might last a long time.

The helpful folks on VMF will talk you through about anything you may have questions about. Just be sure to ask! Better to take a few extra days than have premature engine failure.
 
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