Adjusting valves with engine running ?
Thread Starter
Race Director
Joined: Apr 2000
Posts: 17,676
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Adjusting valves with engine running ?
Put the new Sportsman II heads on the motor is running great. Quite a difference in power especially over 3000 RPM. It just takes off and the sound from the mufflers is much louder than before when you go WOT.
I have developed a ticking in one of the valves so I cut a long slot in one of my old valve covers so I can put it on and not get any oil on the headers.
MY question is how much of a turn do you go after you get rid if the ticking.
Hydraulic lifters 1/4 1/2 or 1 turn ?
I have developed a ticking in one of the valves so I cut a long slot in one of my old valve covers so I can put it on and not get any oil on the headers.
MY question is how much of a turn do you go after you get rid if the ticking.
Hydraulic lifters 1/4 1/2 or 1 turn ?
Melting Slicks
Joined: Mar 2001
Posts: 3,365
Likes: 5
From: Lake Villa IL
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St. Jude Contributor
Re: Adjusting valves with engine running ? (MotorHead)
I do it by ear. A quarter turn should be enough. But I like to listen to the sound of the engine. The idle will drop if you go too far. You want to remove the lash without imparting a negative effect on the idle quality.
Good luck!
Good luck!
Drifting
Joined: Jan 2002
Posts: 1,645
Likes: 11
From: Schaumburg IL
Re: Adjusting valves with engine running ? (MotorHead)
What does the manufacturer of the lifers say? Generally 1/4 turn will give you somewhat higher RPM's. One turn was what GM recommended which was really a failsafe to prevent valve float. I have always used 1/2 turn and not had any trouble.
Melting Slicks
Joined: Dec 2000
Posts: 3,407
Likes: 2
From: Carmichael CA
Re: Adjusting valves with engine running ? (MotorHead)
It depends on the lifters and their condition...did you check them for flatness? If they are concave from being worn out then you should have replaced them so you can use manufacturers specs. But, if you didn't then you should NOT use manufacturers specs, but somewhat less. The specs account for wear so you don't have to adjust them for the life of the engine. If you add lock nuts you can adjust it until it stops ticking then only 1/4 turn, but with stock nuts I would go to at least 1/2, but no more than 3/4.
Thread Starter
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Re: Adjusting valves with engine running ? (Rockn-Roll)
Thanks guys, I have the lock nuts and they are the old lifters. It looks like a quater turn.
I remember trying this before and I gave up because I couldn't hear anything because of the noise coming from the engine. Any suggestions
turning the idle way down ? etc
I remember trying this before and I gave up because I couldn't hear anything because of the noise coming from the engine. Any suggestions
turning the idle way down ? etc
Melting Slicks
Joined: Jul 1999
Posts: 3,201
Likes: 0
From: Clifton Park NY
Re: Adjusting valves with engine running ? (Corellian Corvette)
I think I'll be trying this procedure pretty soon. Is it easy (obvious) to identify the exact point when the rocker stops/starts ticking, or is it something subtle, that requires some "experienced ear"?
Thanks,
-Pedro
Thanks,
-Pedro
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Drifting
Joined: Aug 1999
Posts: 1,468
Likes: 1
From: Kirkland WA
Re: Adjusting valves with engine running ? (Pedro'74)
Oh you'll know. Back the nut off and the thing will start clattering LOUD. Slowly turn just until the clattering stops. Then, give it 1/2 more turn. Move on to the next one. It takes about 5 min per side.
