Posts: 13371
Joined: 3/20/2002 From: San Bernardino County,
CA, USA Status: offline
Most bent crankshafts from a crash can be straightened, at least that is my experience. I get a kick out of repairing things, rather than just replacing them, or buying new parts.
I learned how to true and straighten cranks from the Pro's back in the 70's....I'm very good at it.....I've been doing it for 35 years, professionally. Send me your bent crank, and I will straighten it for free.....no problem.
Flyboy Dave.
< Message edited by Rcpilot -- 6/7/2008 2:44:41 AM >
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An engineer says.... "That won''t work". A mechanic says..."Oh yeah, watch this". "Old Age, and Treachery will overcome youth and skill". Revver Bro #4.
Posts: 478
Joined: 10/18/2006 From: Auckland, NEW ZEALAND Status: online
I too hate buying new parts when the old parts can be resurrected . Why not describe for us your method to straighten a bent crank. Don't be afraid to use technical jargon, and assume we have access to the same machines and equipment that you do.
Posts: 13371
Joined: 3/20/2002 From: San Bernardino County,
CA, USA Status: offline
quote:
ORIGINAL: craigpuckett
I will be sending Dave a very bent LA40 crankshaft as soon as I work off this evening (3-11) shift, prally Thursday
I will try and get a before and after pic, unless Dave wants to as He is doing the job.
Craig....send the case and the crank, so I can check it like this....
Craig is my first customer.....
FBD.
< Message edited by Flyboy Dave -- 1/22/2008 5:52:02 PM >
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An engineer says.... "That won''t work". A mechanic says..."Oh yeah, watch this". "Old Age, and Treachery will overcome youth and skill". Revver Bro #4.
Posts: 6076
Joined: 12/8/2002 From: Valdese,
NC, USA Status: offline
To the naysayers out there. Not naming names but rhymes w8ye and breeze. It's obvious that FBD is using the pictured engine housing as a mount to run the shaft in. No problems with how he has it fixed to his surface plate as a method of holding things in place. To really simplify the straightening proceedure. A whack put it in and a whack will take it out. No hitting shall take place on a surface plate...ever.
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Joined: 7/21/2005 From: Greensboro,
NC, USA Status: online
First, I'm not doubting Dave's expertise in any way. But, I do have a question: How do we know that the mounting flanges on every case are perfectly square, true and in an exact parallel plane to the crankshaft?
David.
< Message edited by rainedave -- 1/22/2008 7:13:41 PM >
Posts: 6076
Joined: 12/8/2002 From: Valdese,
NC, USA Status: offline
RD, the flanges have nothing to do with run-out, there is not a concern about alignment in this situation. This would work even if the shaft were a taper, the trick is finding the point where the bend originates from and working from there.
I don't mean to hijack Dave's thread, I also have some experience in this area.
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Bent crank ? I'll fix it for free. - 
Big Hammer
