350 unkown problem
 

I pulling away from a stop light like normal and I here a snapping sound and the engine shut off. And if I got to crank it I hear a tinking sound and it tried to crank but it don't. Idk if the timing chain broke or what. I haven't tore it apart yet. It seems like if the timing chain broke it wouldn't be trying to crank. Also earlier that night I before that happened I got into the throttle pretty good coming off of a light and when I let out of it around 4500 it wouldn't go down to idle and it stayed at 1400 and when I got home it was back to normal. Any help would be great. Thanks
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Re: 350 unkown problem
 

What engine?

Symptoms indicate stripped cam/crank timing gears or broken timing chain.

Re: 350 unkown problem
 

SBC 350. We just put a new lunatic cam kit in and reworked the heads
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Re: 350 unkown problem
 

sounds like the cam broke

Re: 350 unkown problem
 

You can check to see if it's cam, timing chain/gear by removing valve covers and turning or cranking the engine to see if the valves go up and down.

Re: 350 unkown problem
 

So you are saying the motor turns over when you are trying to start it? And it makes the tinking sound consistantly? or it goes "tink" and stops, and does not move any more?

Re: 350 unkown problem
 

It was consistant but we pulled the head and we found that the #8 exhaust valve had broken and fell into the cylinder but luckily the cylinder wall and everything is fine.
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Re: 350 unkown problem
 

How big of a cam? Did you install new valve springs? Its extremely odd for a valve to just break. Usually they dont break until they are hit by a piston. Once in a while the valve face will break off of the stem. Theres something else wrong. The engine would still run with one dead hole.

Re: 350 unkown problem
 

The cam is 465 intake lift 4.88 exhaust lift 224 intake Duration and 234 exhaust duration @50 and yes new valve springs were installed. The Guy that built my dads motor is the one doing the work and he was able to crank it up. I didn't procced to continue trying to crank it after I heard the noise it was making. And I think that's where it broke at the face.
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Re: 350 unkown problem
 

Cause the stem was still in the keepers
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