Valve knocking?
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 1,241
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From: Oceanside New York
Valve knocking?
Hey all! After turning on my car, i've become rather critical about the sounds that come from under the hood.
Recently i've heard a light ticking...
I'm guessing that it's a valve knock. I've heard a few remedies, but I want to run it past you guys. Any help is appreciated!
Recently i've heard a light ticking...
I'm guessing that it's a valve knock. I've heard a few remedies, but I want to run it past you guys. Any help is appreciated!
Team Owner
Joined: May 2006
Posts: 21,473
Likes: 356
From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
More than likely you are hearing a lifeter tick or a rocker arm tick!
Once it gets warm it goes away - right?
If it does then it is normal wear, you could try a heavier oil or check the rockers for tightness!
If it is lifters then try the heavier oil that will keep them from bleeding down!
Thanks,Matt
Once it gets warm it goes away - right?
If it does then it is normal wear, you could try a heavier oil or check the rockers for tightness!
If it is lifters then try the heavier oil that will keep them from bleeding down!
Thanks,Matt
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 1,241
Likes: 0
From: Oceanside New York
hmmmm...i'm guessing it could be a rocker arm tick? I wish I could record it. I think I keep hearing it while driving, even when warm. I'm not sure, but I listen hard to see, I could be paranoid. I heard it when it was cold. It's a light tick, but it's consistant...ticktickticktick....i've heard people say "like a baseball card on a spoke", but I don't think it matches that sound.
"Valve Knock" was what I heard....Seafoam was a potential fix....not so sure...
"Valve Knock" was what I heard....Seafoam was a potential fix....not so sure...
Tech Contributor
Joined: Dec 2006
Posts: 10,962
Likes: 29
From: Van Buren Arkansas
Wounded Warrior Escort '11
If its a light tapping sound from the upper portion of the engine, then you have a lifter that isn't pressurizing. Most of the time, this will go away within a few seconds. If not and it takes longer, there are several possibilities. First, look for needle bearings coming out with the oil as there is a possibility that a rocker arm side bearing holder, whatever its called, has opened up, therefore the bearings have fallen out. Might need new rockers in that case. Another is the lifter itself may have worn out, but that usually happens with high mileage engines and will require head removal to replace them. There are lots of other possibilities of course but those are the usual.
Team Owner
Joined: Apr 2005
Posts: 23,900
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From: Foxtrot Delta Tango
What you may be hearing is piston slap. "Not the piston rings, it's the piston to bore clearance, cold. One difficuty with multi-metal engines is the coefficient of expansion between the different parts. An LS1 has an aluminum block with pressed in steel liners. Aluminum expands much more quickly than steel causing the bores to go out of round when cold. All is equalized, and square when at operating temp. The lesson here is, be easy on your car when first started, and allow it to warm up gradually before hitting the hammer hard. I do this with all my cars, especially in winter. If you follow this precaution, I doubt you will ever have a problem."
