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440 crank- grind or no?

Sonny

It’s all fun til the rabbit gets the gun.
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I bought this crank from a machine shop on eBay. Listing said magnafuxed, hot tanked, superfinished, “ready to go”. Mains are std. and rods turned 0.010. I was surprised to see the lines and gouges on the mains. If polished (looks like it was) and spots not raised should I install crank as is? I mic’ed the crank and it is std/0.010. See pics below.
Sonny
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It's an ebay crank go have everything checked out by your own machine shop and see what they say.
 
Tell the seller you want to return it. I would not accept it.
 
Looks like it was assembled and stored for thirty years. That's from moisture. If it Mags O.K., you can use it.
If you feel that you want it more perfect you can have the mains ground. It all depends on what you paid
for it. I do agree that if you paid too much for it you should return it!
 
Spoke to the shop directly and he agreed to refund $175 back to me so I can get it turned here in Fl. Didn’t give me any push back. I paid $350 for it plus $65 shipping.
 
Also this is a car show car and not a race car. Won’t see 5k rpm hardly ever.
 
Grinding a crank under is no biggie unless it's a Nitrided Hemi piece. Have the rod
journals chamfered while you're at it. It'll be like brand new.
 
Did you stand it on end and tap each counterweight with a hammer? If it rings like a tuning fork, it's good, if it goes thud, it's junk. The finish appears to be really poor.
 
Did you stand it on end and tap each counterweight with a hammer? If it rings like a tuning fork, it's good, if it goes thud, it's junk. The finish appears to be really poor.
That will tell more if its cast or forged. Not the quality of the crank.
 
Grind the damn thing R20/M10, don't even think about it, and be done with it as long as he is going to return $175. Here, that is more than what the crank grind price is.
 
Did you stand it on end and tap each counterweight with a hammer? If it rings like a tuning fork, it's good, if it goes thud, it's junk. The finish appears to be really poor.
That works with Redwing Crocks too. (hit with a knuckle, not hammer). They can look perfect , yet still go clunk. If you look long enough, you will find the crack
 
You may laugh, but I have used up a number of OEM steel cranks due to my excessive RPM's. The hammer test was always confirmed by Magni fluxing. With a Mopar steel BB crank, if you stand it on end, no bolt in it, hit each counter weight lightly with a hammer, if it rings like a tuning fork, good, if it goes thud like a bowtie crank, no good.
 
Small dings or small pits on a crankshaft don't bother me too much as long as there are no raised areas and the crankshaft measures out like it should.
 
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