Bent Valve

[goatman]

Well, I was replacing the valve seals on my 93 Z, and got almost done with the exhaust side, and found the last valve was bent. whaty would cause just one valve to bend like that? I have hardly enough money to be doing any of this anyway, and now this! I am pissed!

[TheProfessor]

it might have something to do with another part of your valvetrain bing out of whack like the spring or the rocker arm
do the pushrods look alright

[Lyle's GTP]

Did you own the car originally? Cause it sounds like you have been a victim of some "shady dealings".

Lyle

[SappySE107]

pushrods, rocker arms? Its a 3.4 DOHC, not a pushrod engine. I have no clue what would cause just 1 valve to bend out of the pair in that cylinder.

[RednBlack]

You are replacing valve seals? Then you do not have the heads off. I can't imagine how a stem would bend, unless you or someone previously bent it. Either way, you will have to pull the head, replace the valve and the guide, cause it will be shot also IF the car has been running with a bent valve stem.

[goatman]

No, the heads are off, I was planning on having Ben P+P them for me, but money issues are forcing me to wait. The intake valve opposite the bent one is also slightly bent, no where near as bad as the other, but still bent.

[SappySE107]

My only guess now is that one of the lifters or springs failed at one point, leaving the valve open more than it should have been, and the valves hit each other.

If its not bent in the guide area, the guide may not be messed up. Granted it still could be if it was slightly bent at the head and still managed to seat itself from the spring pressure.

[RednBlack]

Not such a big deal then. Guides should be ok and I'm sure someone has valves here on the site.

[TheProfessor]

could also be from someone flating the valves or is there a rev limiter

[Dave]

overrevving the engine and causing the valves to float and smack one an other, or hang one of them up on the other... (that's just a guess tho)

--Dave.

[goatman]

I know that there is a limiter that kicks in at 3000 in park or neutral, I'm not sure where it is otherwise, though.

[blk92z34getrag]

If your car is an auto I doubt it has ever been taken past 6500. I don't even like running my 5 speed past 7k unless I really want to show off. But I have my rev limiter set to 7750RPM.

EDIT: I've taken my car to the limiter (7750RPM) at least once... ... maybe more than that... anyway, the valves were definately not floating.