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Discussion Starter #1
Hi, I took my 302 powered mustang to the track and bent a pushrod. Upon inspection, I noticed that the valvespring is slightly compressed (with no rocker or pushrod to compress it.) Im thinking its a stuck valve which may have bent it.
 

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Or the valve hit the piston is bent and it keeping the valve off the seat.
 

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pushrods bend from the valve hitting the piston.

you cannot just "replace" the bent pushrod and the valve.

or else the damage will continue the next time it runs.

you MUST have someone actually check the piston to valve CLEARANCE then the valves are just opening / closing and piston is just before top dead center...valve opening during "overlap" at T.D.C.
you will have to have the eyebrow of the piston cut deeper to gain the needed clearance.
 

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Discussion Starter #6
I pulled the head and yes the valve hit the piston, but why? I checked piston to valve clearance. The only other thing is that while adjusting the valves, the adjustment on that valve was not consistant with the other ones.
 

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out of work hair dresser
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I pulled the head and yes the valve hit the piston, but why? I checked piston to valve clearance. The only other thing is that while adjusting the valves, the adjustment on that valve was not consistant with the other ones.
Then you had a pre-existing problem. You need to find out why this one was different. Are you on a hydraulic cam?
 

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how much previous piston to valve clearance did you have before the engine had this bent pushrod problem. ???

the exhaust valve os usually still open a little just before it is totally closed BEFORE the piston is actually at top dead center.....and the intake is just opening when the piston is AFTER top dead center.

having clearance when both valves are closed and piston is at top MEANS NUTHING...!!!!
 

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the only positive mannor to check the resultant piston to valve clearance is with a hydraulic lifter turned into a solid so that the plunger does not depress..
 

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Discussion Starter #13
when i checked piston to valve clearance i used solid lifters and used no head gasket. Cleared fine with thick clay. Then i installed .040 head gasket.
 

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Billy438Stroker
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Too long of pushrod along with coilbind can cause the same problem..seen lots of valves bend this way
 

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Discussion Starter #18
I have made 400 passes without a problem, then I had water leaking from between the block and head. The machine shop took .006 off of the block. I also checked and installed new valve springs and set them at the recomended 1.800 intalled height.
 

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how does the collets look are they new or reused??? i broke one on my old motor but only happened in the burnout area so i shut it off man did i save some damage !!!!
 

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Discussion Starter #20
Im thinking i spun a rod bearing. I dumped the oil and saw shavings. I also heard a knock when I turned the motor over.
 
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