Thread: Interference valve train?

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I am not going to bother you guys with the details, but while my engine was on the stand, it was accidently cranked over (by hand and not by me) with the timing chain off. Needless to say, I am worried a valve could have been bent. Its a stock 454 with a mild cam in it. Is this possible on my motor? I know its can be an issue, I am newbie to BBC...

It's very possible it may have bent a valve,was the rocker arms on it and the valves adjusted ???? if not you will be o.k. but if they where you now need to run a cylinder leak down test......

Damn it...
I asked a buddy to borrow a piston stop tool. He dropped it off when I wasn't home and took it upon him self to throw it in the engine and give the mototr a few turns over, not realizing I had the chain off.

I have hydraulic lifters, do you think they would have enough "give" to not bend a valve if turning the engine slowly by hand?

the chances of his bending a valve are pretty slight. If there was enough interference between the valves and pistons to bend a valve he would have noticed it because it would have stopped the piston travel when it touch the vavle head.
He would have had to put a big breaker bar on it at that point to continue to turn it over.