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Motor will not rotate 360 befor it binds on something just replaced heads could it be head or intake bolt too long in a paticular spot?
 

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That's not good!!!

The 350 is very close to being an interference engine (timing chain breaks valves hit pistons). Cold and turning at slow speed they should not touch.

But, as I said they are very close, did you do any mods, like high lift rockers?

It only seems to hit at one spot?
Are you saying you can turn it until it stops, then turn it the other way until almost the same point when it stops again?

Maybe you have one valve that is the wrong length.

Maybe a valve is loose and fell into the cylinder.

Pull the covers and check the valve action as you turn the engine.

Pull the plugs, it will be easier to turn.
 

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timing chain breaks valves hit pistons
All good suggestions. Years ago when I was rebuilding a Mopar 360Cu In I installed the push rods and rockers but forgot the timing chain, stupid move after a long day! The engine would only rotate a little until it jammed. I wound up bending a couple push rods before I realized what I did.
 

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what was the problem before you replaced both heads ?
replacing the heads use the proper head gasket. rotate the engine by using the crank shaft with the plugs out . could be something fell in the cylinder bore.
 

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You may need a bore scope to look into each cylinder.
 

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My first guess is incorrect valve adjustment. Pull the plugs, back off the valve adjustments and readjust in the correct sequence.
 

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D W, I don't think a little adjustment is the cause, the 350 is considered by many to be a non-interference engine, meaning that under extreme conditions the valves and piston should never meet.
I think it is likely that a valve has lost its retainer and has fallen into the cylinder, or, perhaps the OP left a wrench in there.

He hasn't been back, so we may never know.
 

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D W, I don't think a little adjustment is the cause, the 350 is considered by many to be a non-interference engine, meaning that under extreme conditions the valves and piston should never meet.
I think it is likely that a valve has lost its retainer and has fallen into the cylinder, or, perhaps the OP left a wrench in there.

He hasn't been back, so we may never know.
You could be right. The OP stated he "replaced heads". He didn't elaborate when he discovered the engine wouldn't rotate 360 degrees. He would have had to rotate the engine at least 360 degrees during valve adjustment, so I'm puzzled.
 

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Good point. Yes he would have, a number of times
 

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is there a freeze plug between the flexplate and the block? i bought a van for twenty bucks and that's all that was wrong with it.
 

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Good point fart, could be something external causing it to bind.
 
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