Valve Service Question
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Instructor
Joined: Mar 2007
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Valve Service Question
Hey all,
My car is coming up to valve adjustment time. My motor isnt ticking at all...still sounds perfectly normal. What are the dangers or going over the reccomended valve intervals? Lets say the motor did need an adjustment (and I was wrong), and I continued to drive her for a few thousand miles. Would that/could that damage my motor?
My car is coming up to valve adjustment time. My motor isnt ticking at all...still sounds perfectly normal. What are the dangers or going over the reccomended valve intervals? Lets say the motor did need an adjustment (and I was wrong), and I continued to drive her for a few thousand miles. Would that/could that damage my motor?
Burning Brakes
Joined: Aug 2005
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From: Austin TX
that's of course assuming they are loose, not tight. if you can smell them / if they are tight / then that can definitely cause damage, though normally they go loose and are only tight if adjusted incorrectly.
Burning Brakes
Joined: Oct 2006
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From: So. Cal (USA)
Originally Posted by buellrunner
If I can smell them? What do tight valves smell like?
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From: Jacksonville Fl
I have read that the wear point is the inter edge of the valve face. This causes the valves to tighten up over time. I've adjusted my valves now 4 times and found mine get tighter. In order for them to get loose, the shaft would have to compress (unlikely) or carbon builds up on the inter edge of the valve face. I wouldn't go past 15K. If your easy on the car, it might be fine. Mine spends most of it's time at the track so I adjust every 10k or so. Mark
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Drifting
Joined: Jun 2006
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From: Dallas/FortWorth Texas
Originally Posted by WMRiceman
...This causes the valves to tighten up over time. I've adjusted my valves now 4 times and found mine get tighter. ...
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Burning Brakes
Joined: Aug 2005
Posts: 1,090
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From: Austin TX
Mine have always gotten looser. While the valve seating contact surface does wear (and make them tighter), more often the contact area between rocker arm and end of the valve wears down more quickly, making them looser. The other thing that might tighten them up is a head or cylinder lifting due to a head stud/nut loosening up - but of course that would be very bad. If you don't hear them and it's time to check - go ahead and give them a check - better safe than sorry. If they're too tight you'll burn a valve.
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From: Atlanta
I just finished a valve adjustment. Last time was 20,000 miles ago. All valves were still fine. I may go as much as 30,000 miles before I do it again. I drive on streets only, and US speed limits evidently keep the engine from needing adjustment as often as the factory recommends.
I would definately check if you do not completely trust the person that adjusted them last time. Not everyone takes a lot of care and I would worry about that except I personnally attended to it. I have seen blue cam lobes and blue rocker arms - overheated during a race because the valve seat evidenty was beaten in, or perhaps the valve head broke of and the motto was "press on regardless".
I would definately check if you do not completely trust the person that adjusted them last time. Not everyone takes a lot of care and I would worry about that except I personnally attended to it. I have seen blue cam lobes and blue rocker arms - overheated during a race because the valve seat evidenty was beaten in, or perhaps the valve head broke of and the motto was "press on regardless".