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Discussion Starter #1
no explanation needed. the pics say everything. i got lucky and had minimal other damages. the stator and flywheel are wrecked because they were rubbing on each other. i think the crank was broke for a while (or at least bent). it also threw of my timing and bent the exhaust valves. intakes seem to be ok. there is no evidence of contact between the two on the piston or the intake valves.

i know i have seen a handful of broken hotrod cranks on the forums before. is the flywheel side the side that normally breaks? it would make more sense if the drive (clutch) side would break in my mind...

i will be purchasing a barker 4 mill crank this time. i should have bit the bullet and purchased the more expensive one to begin with... here are some pics of my new paper weight.









 

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that sucks
 

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Discussion Starter #4
How long did this run for before snapping?
it was installed in winter of 07-08. i dont remember exactly when, but i know i tore it down over that winter. as far as how many hours....if i had to guess i would say around 100-125.
 

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When mine broke just like that I was told it was from the bearing being pressed on the crank to far and scoring the crank and making a weak point and eventually breaking. I believe I caused mine when pressing it on the cases, Even though I don't want to admit it. Just a FYI this has happened on barker's cranks to. I believe it is caused when installing the crank??? I was more careful putting in my second crank.
 

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you dont have to press them into the cases, wth. just freeze the crank and heat the cases and it drops right in. the pressure you put on the crank when pressing it into the cases may have something to do with it.
 

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When mine broke just like that I was told it was from the bearing being pressed on the crank to far and scoring the crank and making a weak point and eventually breaking. I believe I caused mine when pressing it on the cases, Even though I don't want to admit it. Just a FYI this has happened on barker's cranks to. I believe it is caused when installing the crank??? I was more careful putting in my second crank.
I personally have never seen one of theses cranks live when broken, but my suspicions are that the crank and bearing races touch causing a mark to start in the radius of the crankshaft to the web area, this causes a stress riser and it will break at that point, this can easily be remedied by install a shim between the bearing and crank web...........
 

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I personally have never seen one of theses cranks live when broken, but my suspicions are that the crank and bearing races touch causing a mark to start in the radius of the crankshaft to the web area, this causes a stress riser and it will break at that point, this can easily be remedied by install a shim between the bearing and crank web...........
Like willy said if you look where it broke on the surface I bet it is in a perfect circle ....like a bearing race. I didnt wanna believe it when mine broke that I might have caused it but After looking it over real good I think willy is right.....but he is the master
 
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