Breaking in new rebuild (knocking)
#1
11-28-2009, 03:40 PM
Breaking in new rebuild (knocking)
I have just rebuilt a 350 engine for my truck. The bottom end was done at a machine shop. Heads,push rods, roller rocker arms, intake, valve covers were installed by myself.
the problem I'm having is when I turn the engine on to break it in, theres a loud banging/knocking noise coming from the engine. It's more then a loose or sticky rocker arm ticking. The noise does increase as rpm goes up. I checked the PSI (compression) on it and the #2 cylinder has about 175 to 180psi compared to all others at a 150psi. Also the header tube on the #1 cylinder is cold when all others are warm/hot.When checking all the plugs they all have signs of ignition.
I'm not sure what it could be right now, either a bend push rod or maybe the rocker arms could be hitting the valve cover's which are aluminum so it might make a louder noise but it definatly sounds like metal on metal contact somewhere. Any help or ideas would be great!!!
the problem I'm having is when I turn the engine on to break it in, theres a loud banging/knocking noise coming from the engine. It's more then a loose or sticky rocker arm ticking. The noise does increase as rpm goes up. I checked the PSI (compression) on it and the #2 cylinder has about 175 to 180psi compared to all others at a 150psi. Also the header tube on the #1 cylinder is cold when all others are warm/hot.When checking all the plugs they all have signs of ignition.
I'm not sure what it could be right now, either a bend push rod or maybe the rocker arms could be hitting the valve cover's which are aluminum so it might make a louder noise but it definatly sounds like metal on metal contact somewhere. Any help or ideas would be great!!!
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