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Exhaust valve

what can cause a bent exhaust valve?

A bent valve will cause very poor operation, very rough running, very poor mileage, and possible damage to the piston. A bent exhaust valve will allow raw, vaporized fuel to go straight into the hot exhaust. It can cause a kaboom. Depending on the car’s design, the forces of the kaboom could cause other damage, like a broken oxygen sensor or a crumbled ceramic honeycomb in the cat converter. Again depending on the design of the car, particularly its exhaust manifold, and the moment the fuel ignites, the kaboom could even back up elsewhere and cause other havoc…

can it also cause low compression?

It will cause zero compression in the cylinder that it serves.

so, therefore the engine will not run right?


so how can i fix this problem myself?

So how does an exhaust valve get bent and who diagnosed this? If this is a broken timing belt issue the intakes are the valves that usually bend.

i found the problem

No disrespect meant, but the questions you’ve asked suggest to me that you’d be in “over your head” in attempting to fix this yourself. Replacing a bent valve is a fairly high level procedure. It also requires some specialized tools. And, as already suggested, of the cause of the bent valve was a broken timing belt, you may have more than one bent valve and you may even have piston damage.

How did you find the problem?

i took the cylinder head off and found the small valve was bent which is the exhaust valve

I mean no offense, but I’m confused. You ask us how an engine works, but then have enough technical ability to tear one down?

Because I want to know what the exhaust valve does if it is bent.

actually i am trained in mechanics.

If you’re trained as a mechanic as you say…then why are you asking about how to fix a bent valve???

Confused here also. You’ve done the hardest part of the job already…You removed the head. On some cars that’s a LOT of work just to remove everything so you can remove the head.

I’ll bite. Is this a Honda?

If he hasn’t completed the repair in the 8 months since he started the thread, he has a real problem.

i fixed it the same day thank you very much

automechanic1993: Please write in full sentences like you had to do in school, or like you would in a letter. It is annoying to have to read something that looks like you are texting someone, and your one-line replies don’t have a lot of information content.

I’m not trying to put you down, but if you were talking to someone face-to-face, would you talk like you’ve been writing here and expect to be understood? Would someone take you seriously?

If you fixed it in one day, congratulations. Out of curiosity, what did you use for a replacement part?