Originally Posted by strokerman
Hello everyonei have an 1985 chevorlet custom deluxe shortbed truck with an 383 stroker motor,one of the rockers came off and i had 2 busted valve springs and two bent push rods,ok!took it to my mechanic he said he thinks it has a bent valve,but,when he ordered the new springs they sent single ones instead of double ones,so he reordered new ones,but in the mean time he tried the single one to see what would happen,he said the valve would not come back up,could the single spring not be strong enough?he said he thinks the shaft on the valve could be bent,but would not know for sure til he pulls the head,my question is how difficult is that to repair and costly?hopefully it didn't damage the piston,just wondering?i'm a single dad with limited funds,thanksplease repond!!!
The valve should easily be able to be seated w/just a single spring- IF it's not bent. So, it sounds like the valve has been bent in the process.
What caused the bent pushrods, and broken rockers? Over revved? If not, the entire valve train needs to have ALL the clearances verified, among them (from another thread):
It is common practice when installing new heads, or pistons, new cam, different ratio rockers, springs, etc. to check:
- Springs for installed height
- Seal to retainer at full lift
- Valve to piston (also both before and after TDC on overlap)
- Push rod to guide slot in head (if used)
- Rocker to valve tip (by adjusting guide plates if used)
- Rocker slot for adequate length (if using stamped/cast rockers w/pivot balls)
- Proper geometry (push rod length)
- Rocker/polyloc to valve cover
Prolly something else I'm missing. But it has to be physically checked, you should not take it on faith or by figuring it out on paper.
The piston could
be damaged- the valve, if bent, did hit the piston, after all. Sometimes, the damage isn't great enough to cause the piston to need to be replaced. There certainly ARE cases where the piston is totally trashed; you'll need to assess that when the head comes off to repair the valve(s).
Good luck and let us know what's up.