Corvette problem
Thread Starter
4th Gear
Joined: Nov 2015
Posts: 4
Likes: 0
Corvette problem
Hey guys got a 79 vette with a 350 makes a very distinct metallic rattle at low Rpm acceleration sounds like left rear does have heat shield on right side pipe but nothing on the left side, left side pipe does leak a little bit but I've check everything can this be from the exhaust leak or otherwise...I did find a small crack by manifold bolt are these the possibilities?
Also did notice a crack on the left side manifold to the exhaust pipe
Also did notice a crack on the left side manifold to the exhaust pipe
Melting Slicks
Joined: Apr 2009
Posts: 2,632
Likes: 112
From: Great Plains Iowa
Hey guys got a 79 vette with a 350 makes a very distinct metallic rattle at low Rpm acceleration sounds like left rear does have heat shield on right side pipe but nothing on the left side, left side pipe does leak a little bit but I've check everything can this be from the exhaust leak or otherwise...I did find a small crack by manifold bolt are these the possibilities?
Also did notice a crack on the left side manifold to the exhaust pipe
Also did notice a crack on the left side manifold to the exhaust pipe
I have found an exhaust leak at the manifold/head union makes a distinct tapping sound whereas down lower its more of a whacking sound and further back a poofing sound. Plug your worst ear with a foam plug then hold a 4 foot piece of 5/8" garden hose to your best ear while probing for the sound. The hose will block out all of the other noises so you can easily pinpoint the source of the noise.
Safety Car
Joined: Jan 2009
Posts: 4,000
Likes: 299
From: New York
I here ya ! For me the whacking and poofing go away when the drugs fade and the alcohol causes me to pass out . After that the car is quiet as a church mouse at mass on sunday in rome ..
You could try this .
Does it do it when in park at idle ?
If so have a friend close off the exhaust out lets briefly and while he does that you search for noise . If you get multiple noises you have multiple leaks to fix .
You could try this .
Does it do it when in park at idle ?
If so have a friend close off the exhaust out lets briefly and while he does that you search for noise . If you get multiple noises you have multiple leaks to fix .
Racer
Joined: Apr 2008
Posts: 406
Likes: 46
From: Lebanon OH
Do you still have the EFE valve? If so, there is a metal clip that attaches the valve bar to a tang on the the butterfly valve in the exhaust. If that comes off, the butterfly valve will move around, causing the tang to hit the exhaust pipe or manifold.
Actually...the tang hits the valve body and not the pipe or manifold, but it still makes a metallic sound when that happens.
Actually...the tang hits the valve body and not the pipe or manifold, but it still makes a metallic sound when that happens.
Last edited by MajD; Nov 14, 2015 at 08:09 PM. Reason: Incorrect information.
