| Engine Noise [message #225107] |
Thu, 10 October 2013 18:03  |
Darryl
Messages: 144
Registered: December 2011
Location: Northern California
Karma:
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78 403 with headers. 62,000 miles. I've been chasing a noise in the engine for the last 2,500 miles or so without any success at identifying it.
It's more of a loud "tick" than an knock. I put a timing light on it and the noise is in sync with the light so it should be in the valve train. I put a stethoscope on it and it seems to be in the driver's side head but I can't really tie it down to a particular cylinder. Through the stethoscope it sounds like light metal-to-metal contact. Pulled the valve cover and ran it - all the rocker arms and push rods seem to be functioning properly. Pulled spark plug wires hoping it would go away without one cylinder firing but no help. Put a hose down by the exhaust gaskets hoping for an exhaust leak but I don't hear or feel anything. Someone suggested pulling the carburetor to check for cracks in the intake manifold but a cracked manifold should make the engine run poorly (it runs fine) and I can't see how it would cause the noise I'm hearing.
It's only noticeable at idle, louder when cold and goes away when I put a little load on the engine. I just did an 1,100 mile round trip to Coos Bay. The engine ran great and the noise isn't any worse now than when we left.
We've got a 2,500 mile trip planned for the end of the month which I'm thinking about canceling until I can get this figured out. Anyone have any ideas?
Darryl Meyers
1978 Eleganza II
El Dorado Hills, CA
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