Im the original owner. I was convinced it was the idler when i first heard it.
So I replaced the idler.
Its quiet with the belt off for a 20 second run.
Put it all back together, same knock.
Neither of these would typically cause a knocking sound.
robpp, buy or make a mechanics stethoscope, and determine more closely where the sound comes from. Common and more logical suspects are a loose flex plate bolt, a cracked flex plate, piston slap, a broken piston skirt, or a rod knock.
if that's the case then it isn't the engine, it's in one of the items driven by the belt
i'd vote for waiting; it'll definitely get worse, then it'll be easier to find
i been driving it. Im working on a backup just in case.
but right with belt off its quiet.
maybe its right at the front of the crank/harmonic balancer end.
i am only a shade tree mechanic but Im going to get my manual out and look at that area.
what im saying is lets say its internal but it only makes noise when the balancer has TENSION.
is that even possible?
i been driving it. Im working on a backup just in case.
but right with belt off its quiet.
maybe its right at the front of the crank/harmonic balancer end.
i am only a shade tree mechanic but Im going to get my manual out and look at that area.
what im saying is lets say its internal but it only makes noise when the balancer has TENSION.
is that even possible?
Well I did mention in my original reply it sounded exactly like when my A/C pulley bearings went.
Check each pulley on your Serp belt array and see which one doesn't sound/feel like the others. If you got a bad bearing, there will be more resistance in the pulley.
Its just a guess, but it only takes a few minutes to test and doesn't cost any parts, just time.
I like to follow the KISS rule (Keep It Simple Soldier). Start with the easiest & cheapest things to rule out and check first, moving up the line on complicated/expensive, until you find the source.
I followed your recommend. In post 5 I said I brought it to my buddy's shop he checked everything with belt off then put back on and used a fancy snap on stethoscope to listen to each component.
If you take the belt off the noise goes away. The only thing that I've ever experienced that makes that happen is a bad pulley, or a pulley that's been displaced on the array and its hitting something else.
Did he listen to the pulleys with a load on them? I'd assume so. If its not the pulleys, its something related since the noise goes away when they're not under load.
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