Bent valves?

[killab443]

I took valves out of my head because I thought the valves may have been bent and they dont appear to be. Can they be bent and not appear it outside of the head/?

 

[Defiant]

No, but to find out for sure, center them up in a lathe, mill or drill press and measure them.

 

[GTM]

I took valves out of my head because I thought the valves may have been bent and they dont appear to be. Can they be bent and not appear it outside of the head/?

There are a couple of other ways to check without a trip to the machine shop.

Method 1
Hopefully you can put the valves back were they came from. Wipe the valve face and seat clean, no rag threads, bits of carbon or any other foreign particles. Screw the spark plugs in snug. Rest the head on a couple blocks of wood upside down. Slap each valve down a couple of times then fill the combustion chamber with solvent, and let it sit for a while. If they are good then you won't have any leaks and nothing is bent. If you have any dirt they will leak.

Method 2 Grease based lapping compound.
Lap the valves with grinding compound for 10-20 seconds, examine the face and the seats, you should be able to see the lapping marks on both the valve face and seats all the way around.

If you have never done this before get 8"-9" long piece of fuel hose that will fit about 1" on the stem when the valve is in the head. You can now put a dab of compound in about 4 places and then roll the hose between the palms of your hands like you were trying to get them warm. Back and forth as you pull gently all the while rolling the hose. About every 5-6 cycles push the valve off it's seat to draw a little new compound into seat. Essentially you never stop rotating the valve back and forth except to take a new grip or add a little new compound. When you pull the valve out don't let the stem touch the seat.

You will need a couple shop rags to wipe the compound off the seat and face. Do not use these rags for anything else, don't put your valve down on them and keep the stems clean, if you get compound on the stems and then push into the guide you can imagine what will happen.

Cheers,
GTM