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Old 10-09-2012, 06:13 PM
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Originally Posted by Monte84 View Post
I had short block done by local machine shop {wham race engines} have not pulled heads yet double checking cheaper fixes first. Engine has about 200 miles on build-up. Noise started within last 5 miles checked all lifters,pushrods,rockers,accesories,transmission,f uel pump,fuel pump rod,distributor,valve springs, and headers.
Pulled engine and did a visual look at bottom end did not see any problems took oil and filter back to machine shop to have builder look at filter and check oil. The owner cut filter open and said filter looked normal for first filter and oil (second oil change) looked normal except running rich, probably from alot of idle time looking for problem.
First, get a handle on the total timing and the advance curve. Start by making a temporary timing tape so you can see what the total timing is w/o a dial back light. Advance curve info here. You need to do this regardless if it's the problem or not. Not knowing what you have for total timing can cost you an engine.

Then be sure it's not an accessory like the alternator, fan clutch, or power steering pump, etc. Even an exhaust header leak can sound just like a knock- I mean JUST like one, and it's fooled experienced guys, too.

You can use a mechanic stethoscope to listen for where the sound is coming from. If you do not have one, use a length of rubber fuel line. Hold one end to your ear and use the other end to touch around the heads, accessories, etc. to see if you can isolate the noise. BTW, do NOT use a screwdriver held to the side of your head. One slip and that screwdriver can end up sunk into your brain.
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