Rebuilding 6 bolt, crank is FUBAR'ed...Help

[EcliptikIlluzio]

Well I am rebuilding my 6 bolt and the crank is seriously damaged really really bad. The journals under the bearings and the cylinders and all is fine. I need a new crank. Where can I get a good standard crank from? I looked up one from Advance for $190 but it is remanufactored and I don't know about it. I call Jackson Auto Machine and they have one for $260 that has been cleaned and micropolished. Any ideas? Which one should I go with or do you guys know of a better place? Thanks.

 

[MNGSX]

What is wrong with the current one.. Be specific.

 

[EcliptikIlluzio]

The current one is scratched really really bad. So bad that I can visually see it and that barely rubbing my finger on it will show the ridges in it. The bearings were the same way. I flipped the car when the rear end locked up and threw me in a ditch and the car was still running while it was on its side.....oil starvation most likely damaged the crank I think. Also I read something about DSM cranks not liking to be turned. Point is those scratches are extremely deep in some places. I will be taking the block and crank to a machine shop but I wanted to get you guys opinions first.

 

[MNGSX]

You can turn it..

YOU MUST get it Ntride Hardened this is also sometimes called atufftride treatment.

As long as that is done after turning it and the bearings match there is no problem.

 

[EcliptikIlluzio]

Would any machine shop that turns cranks be able to do that or just special ones?

 

[MNGSX]

Some can do it, some cant, and some can but will forget to unless you tell them to... etc... Just ask them.

 

[EcliptikIlluzio]

Thanks for the help man.

 

[Enraged78]

Remember, most shops do NOT know how to properly Nitride harden a crank, and will charge you a pretty penny for it.

A much easier way is this: Go to a local DSM shop or junkyard with a penny in hand. Get a crank, and scratch the penny on the journals. If the penny leaves a copper trace on the crank, it needs to be re-nitrided, and isn't worth the money. If the penny does not leave a copper trace, have the crank micro-polished at a reputable shop, and ask them to give you the micrometer numbers when they are done. Take the numbers to your DSM parts folks, and have them order the appropriate bearings. Usually with a micro-polish, you can get away with stock sized bearings, as the clearances don't change much. Do all this, and you'll have a cheap, good crank with matching bearings. I did this, and having the crank polished and the bearings to match it cost about $150.00, but this was because I already had a good crank. Including the cost of the crank, you should be able to do this for around $300.00 if you know some good DSM folks.

Matt.