Crank has 1 mm of play

I’m sure Brian or Jimbo will chime in but from dealing with clones and flattys I certainly wouldn’t consider .040 of end play any reason to scrap it. Just my 2 cents.
 
Kartiac Arrest said:
Newer to me l206. Crank moves in and out about 1.1 mm. Is this engine scrap?
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I'll admit that's excessive if it's from the factory.
Is there a chance that someone has tampered with the seals?
It's probably just fine @ .040", but that's not within my spec.
If it's not been tampered with, then it makes me wonder what has worn - crank shims, bearings, block...and why - lack of oil at one point?
Hey, you've got it - run it.
Watch the oil -- (I might suggest one of our magnetic oil drain plugs.)
Do a leak down and watch the performance. If the crank is walking back and forth that much, then the rod is likely riding up on the radius of the crank journal at times - which puts the piston in a bind in the cylinder. Remember, there are no bearings in these rods.
Keep an eye on everything and shortblock it for $300 if it starts to go south on you.

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Thank you for the responses. It is a well used motor. I plan on firing it up and leak down testing it. Will go from there!
 
Yea, either a good candidate for building up bigger, or you could simply have a cylinder head issue. Head gasket failure is fairly common on engines that have been raced hard and put away wet. Also make sure that there is valve lash -- some builders use negative lash. For it to be leaking 14%, there's got to be something more wrong with it than excess crank endplay.
Out of curiosity, as you are checking your leakdown, take up the endplay in the crank (ie push the crank hard one way, then the other) and continue to monitor your leakdown gauge. If the rod rides up on the radius of the crank journal, the piston will be cocked in the cylinder and cause additional leakage.
Either way, you've got something that needs some attention - pull the head and check it a little deeper, then decide if it's worth retaining as a 206 with a fresh-en up of the cylinder head, or build that rascal up into something stronger, BP animal, Jimbo's superstock, limited modified, or a small block open.
 
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