[SupraFreak]

I have a 6M-GE motor with a problem. The previous owner let the crank bolt come loose. It caused the the key to be stripped completely off of the crankshaft. The crankshafts on 5M and 6Ms are different. I am wondering if the 6M and the 7M have the same crankshaft. I appreciate any advice anyone can give me.

 

[SilverMk2]

Get one out of a 7M, same thing. Make sure you fit the main and rod bearings correctly. The 6 and 7M both use the select fit main and rod bearings.

 

[SupraFreak]

I've heard that the 6M and 7M were very similar. Now I just need to find a 7M. Do you know which parts are the same on each motor? Aren't 5M heads and 6M heads the same? 7M and 6M bottom end same? Thanks for the help.

 

[pdupler]

A good machine shop should be able to repair the keyway. They can fill the mangled area with weld and regrind or grind a new keyway on the opposite side plus the pulley. Then there's always the emergency pit repair of putting a single tack weld between the crank and the pulley that you can grind off later but thats only if you absolutely have to get back on the road ASAP.

Phil D

 

[SupraFreak]

I already put a different motor in my car. The motor with the messed up crank is going to go in my other one. I'm in no hurry right now to get it going. I want to get everything right. Do you know about how much it would cost to get it machined? I think it might be cheaper to find a 7M crank and pulley.

 

[SilverMk2]

You need a 6M pulley for a 6M. 5 and 7M crank pulleys are different from a 6M.

 

[Jay]

The machine work probably wouldnt cost too much, thats not a big job if you just bring them the crank, but if you are going to pull it anyway, you might as well replace it - you be pretty pissed off if you put it all back together and it breaks again.

 

[SupraFreak]

You need a 6M pulley for a 6M. 5 and 7M crank pulleys are different from a 6M.

I was afraid that was the case.

 

[Tommy]

I have the exact same problem with the crank in my 5M. It will cost me $150 to get it fixed. That is a little more here in South Dakota because we only have like 2 or 3 machine shops close. If you are in a big city with more shops it might cost less. As far as finding a new crank I have been looking everywhere and the only hits I have found for a 5M crank have cost the same after shipping but they all needed some minor work on the journals (ie polishing). I can take my crank which has emaculate journas and have it fixed for less and they say it is just as strong when done. They said they do it a lot.

I am just getting the money toghether to have all my machine work done at once and they will shoot me a deal. Block, crank, rods and head work.