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Need some help from you motor guys


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Please be sure to read all of this first. Para 2 has some enlightenment maybe

Ok so I am still trying to diagnose my engine noise. A knock tap type sounds. It makes the sound a tiny bit at idle but the second you put the motor under load you realy hear it. I drove to the machine shop that built the motor(circle track motor guys)3 of the engine guys came out to listen. All three instantly said that the noise is not a rod or wristpin. One guy popped the throttle while it was running and they listened. They told me if it was a rod or wristpin you would hear it the same or even more on decel. They told me it sounded like a chain tapping something under load, and when load is off, the tension goes to the opposite side of the chain and no tap.

That reminded me, when I was putting the motor together the tensioner guide fit very very tight on the little shaft it pivots on. Tight enough that the spring and plunger would not push it back to tension the chain. I think too many beers because I had forgotten about it until this noise started getting louder.

My buddy is taknig th efront covers off the motor tuesday. I just want to give him so additional ideas of what to look for since this may be an 02 specific issue or sound.

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I don't agree that the tension changes sides on the cam drive chain. The chain is always pulling over the cam and has nothing to do with flywheel/car inertial on decel. Ever try turning the cam over by hand? The chain never pulls on the passenger's side. The tensioner just takes up the slack and has no load on it other than from the whimpy spring. The hydraulics stop the tensioner from retracting away from the chain.

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