BBC valve noise?
Thread Starter
Melting Slicks
Joined: Aug 2005
Posts: 2,606
Likes: 5
BBC valve noise?
This is sorta OT, but still related as we're dealing with a 454...
My boat has a 454 with a mild cam and hydraulic lifters. When cold, I have what sounds like a valve making a distinct metallic hammering sound. As the motor warms up, the sound quiets down some, but is still present. Motor runs fine and I regularly run it at 5500 rpm...has not self-destructed yet.
So...is this noise caused by a lifter, valve or bad valve spring? In what order would I start checking/replacing stuff? I want to avoid removing the heads if at all possible due to the cramped working conditions and the fact that the manifolds weigh 100lbs...
My boat has a 454 with a mild cam and hydraulic lifters. When cold, I have what sounds like a valve making a distinct metallic hammering sound. As the motor warms up, the sound quiets down some, but is still present. Motor runs fine and I regularly run it at 5500 rpm...has not self-destructed yet.
So...is this noise caused by a lifter, valve or bad valve spring? In what order would I start checking/replacing stuff? I want to avoid removing the heads if at all possible due to the cramped working conditions and the fact that the manifolds weigh 100lbs...
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
sounds like a lifter just not quite adjusted in the happy range. They adjust same as on anything else. Pull the covers and adjust for zero lash up and down methode, not turning the pushrod, give it a half turn and fire it up. If it still clatters, see if you can idintify which ones are clattering and give a lil more turn, not more than 1/4. If you have to go more than 3/4 to a full turn that lifter may be bad. While you have the covers off be sure and inspect the keepers and rocker contact points.
Thread Starter
Melting Slicks
Joined: Aug 2005
Posts: 2,606
Likes: 5
Thanks. I'll give that a try.
Any ideas on how to adjust & test-run without re-installing the valve covers? In order to remove the valve covers, I must remove the exhaust manifolds. In order to run the motor, I must install the exhaust manifolds...
Any ideas on how to adjust & test-run without re-installing the valve covers? In order to remove the valve covers, I must remove the exhaust manifolds. In order to run the motor, I must install the exhaust manifolds...
Thread Starter
Melting Slicks
Joined: Aug 2005
Posts: 2,606
Likes: 5
Originally Posted by 73, Dark Blue 454
Do you know what cam is in the engine? Some cams can be noisy, such as Comp's XE line. The steep ramps cause the valves to 'slap' shut and that could be what you're hearing.
However, this noise is coming from one particular spot. I can almost put my finger on it. Sounds like someone is inside the valve cover hammering away (with a very small hammer). Tink, tink, tink, tink....
