Compression Tested Plz Help
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Joined: Feb 2009
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From: Leesville, Louisiana
Vehicle: 2001 Hyundai Tiburon
QUOTE (Stocker @ Apr 3 2009, 07:04 PM)
If the valves are not mating properly with their seats, they will not seal right and compression may be lost through the closed valve.
Lapping is a process of using extremely fine abrasive slurry (valve lapping compound) and rotating each valve's face against its seat. It is a poor man's valve job, and can correct very minor imperfections in the valve seal.
Lapping is a process of using extremely fine abrasive slurry (valve lapping compound) and rotating each valve's face against its seat. It is a poor man's valve job, and can correct very minor imperfections in the valve seal.
Aren't the valves supposed to be perfect? Wouldn't that defeat the purpose of a valve job? I would never attempt anything with the valves by hand. If you polish a bit more on one side then the other, it could widen it enough to break the seal. Explain more please? How do you ensure evenness?
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Joined: Sep 2001
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From: Pflugerville, TX
Vehicle: 2000 Elantra
you people have never heard of www.google.com?
There is a valve guide in there that holds it straight, at the very least.
Lapping the valves subsequent to a valve job by a decent shop would be a waste.
If the head was compression tested and checked out okay, you are all set already and no need to lap or re-cut the valves.
There is a valve guide in there that holds it straight, at the very least.
Lapping the valves subsequent to a valve job by a decent shop would be a waste.
If the head was compression tested and checked out okay, you are all set already and no need to lap or re-cut the valves.
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Joined: Feb 2009
Posts: 11,732
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From: Leesville, Louisiana
Vehicle: 2001 Hyundai Tiburon
I see. that actually sounds like a good idea. I was picturing the valve being all squirly and trying to keep it straight. That sounds like a great at-home way to do a valve job.
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Joined: Sep 2001
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From: Pflugerville, TX
Vehicle: 2000 Elantra
Lapping valves is the shadetree mechanic way to not spend $60,000 on a new Serdi machine. It will get the job done, but a high quality head shop would probably rank it right up there with re-using head gaskets.
Not to say I won't see if I can get away with lapping instead of a proper valve job, but I'm broke and chee- ee- eeap
Not to say I won't see if I can get away with lapping instead of a proper valve job, but I'm broke and chee- ee- eeap
