noisy valvetrain
Thread Starter
Racer
Joined: Dec 2004
Posts: 336
Likes: 0
From: crystal lake Il.
noisy valvetrain
I`ve got a 383 with an xe274h cam. The motor runs great. no issues except the valvetrain seems to be on the noisy side, not any one valve but overall louder than I like. Is this normal with the xe comp cam?
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,116
From: Crossville TN
If your engine has hydraulic lifters or roller lifters, it shouldn't be noisy. If you have solid, flat tappet lifters, there will be some noise. Sounds like improper 'lash' adjustment or you have an abnormal wear issue due to valvetrain geometry or inadequate lubrication.
Le Mans Master
Joined: May 2006
Posts: 9,993
Likes: 1,136
From: League City Tx
You may need a touch more preload. What rocker arms? Ofcourse it could just be the aggressive lobes of the XE series.....and/or the type of lifters. Could be completely normal. I have a hyd roller on a billet core and Morel hyd roller lifters and mine make a decent amount of noise. When completely warm, it's not too bad, actually have to lean down some and listen for it, but definetly louder then a stock hyd flat tappet setup....when cold, they clatter like mad for a few mins....adding another 1/8 turn of preload(now at 1/4 turn) helped a tad but it's still rough when cold.....just the nature of the beast...
Becareful adding more preload so you don't get your valvetrain geometry off...
Becareful adding more preload so you don't get your valvetrain geometry off...
Thread Starter
Racer
Joined: Dec 2004
Posts: 336
Likes: 0
From: crystal lake Il.
They are hydraulic flat tappet. If I adjust them with the motor running I just back off till it makes noise then tighten till quiet and stop. no more 1/2 turn. It might not be the best way for adjustment. but it sounds easy. I have covers with the tops cut out and the rockers are rollers so not a lot of oil all over.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,116
From: Crossville TN
If you don't add 1/2-3/4 turn more on the hydraulic lifters, you are not really using them. When the "lash" is removed to the point that the clacking noise on that lifter is quieted, you have just set the adjustment at the beginning of the piston travel in the lifter. You need the additional 1/2 to 3/4 turn (CW) to center the piston in the lifter so that it will work properly. That is likely where your 'noise' problem resides.
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