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BenKeith
02-04-2005, 09:02 PM
How much pitting can the crank take a still last? I bought a 3.0 OMC looper that was suppose to only have #2 piston bad. Pulled it down and #1 was the only good hole, VRO quit, no oil played havoc.

# 5 journal on the crank has a 1/2" area the width of the journal that started pitting, probably 30 or 40 small flaws in this area. After polishing with 800 grit. The crank mics perfect but was wondering what kind of use I might get out of it at no more than 6,500 rpm.

I figure if there's a chance it will run, I'm gonna run it. It it goes out, the crank would be considered trash anyway so what's one more rod that it will take out. If it welds, breaks the rod, and saws the block in half might get a little too exciting though.
H2OPERF
02-04-2005, 09:35 PM
Spalling or separation of the hardened surface will continue to grow and it will eventually throw a rod and waste the block.If you think its pitting from past surface rust and the area is random, not in lines where the bearings sat it may hold up. Got as picture?Dave
BenKeith
02-04-2005, 10:09 PM
Dave,

This was definetly by the bearing causing the surface to come apart. This was the first teardown for this motor. There are a number of small dots and lines on the surface of the crank in that area where you can tell if it had run longer it would have started eating the crank bigtime. The rod was groved rather badly and had started turning blue. I have a picture but don't have a clue how to post it.
rock
02-05-2005, 08:21 PM
Save yourself the pain and suffering and contact Dave Eden at 949-222-9006. He has rejuvenated several cranks for me and they have always held up well. I hope the phone number is still good.
Rock
bill mason
02-06-2005, 11:07 AM
Do yourself a real favor, give Cy a call at 860-683-1317 or his site is neecaprecisions.com/home Crankshafts are completely hardned. Welding them is a patchwork fix. What he does is take the exsiting material and turn it down and put a oversized bearing on the crank. Makes a much better repair proceedure. Give him a call, nice guy and he is very knowledgable. He won't steer you wrong.