Thread: broken cam

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I just broke the cam in my 71 429. there was oil to the rockers and in the valley. what would cause this? I was diving it normally and there was no noise the motor just started stumbling and missing.

Dude this sounds like trouble. I just went through this and am still rebuilding. Is anything else broken? check lifters above the cam and rods that are below. Is there any debris that may have come into contact with the cam while it was moving? What kind of break and where?
Beware of bent valves as a secondary casualty. If the cam stops moving but the crankshaft doesn't.......somewhere open valves get smacked.
keep us posted!
chris

New cam, old cam? How many miles on it, and what has it's prior use been???? Certainly is time to check for other damage, and determine what cause the break.

the break was about half way on the cam the back 4 cylinders had no movement in the valvetrain. there were about 10 thousand miles on the motor. the cam came out alright and i don't see any derbries or burn marks on the cam so i will drop the pan clean it out and put a new cam and lifters in and see. cylinder leak down was good.

did the cam actually sever or crack? did it come out in one piece? Really look good at the pan and also the cam bearings. I would also get a good look at the valves, maybe handlap them to see if they make good contact on the seat or if they are bent?