Engine Rattle?

Daishi · 01-20-2011, 04:56 PM

Quote:

Originally Posted by 1slow370

no i mean my crank was walking, there was nothing wrong with the pulley the thrust bearing was gone out of the engine and since the crank pulley is attached to the crank you could move the whole crank shaft back and forth by pushing/pulling on the crank pulley. If the car just sounds different with no accompanying vibrations to co with it chances are your bearings are fine, it might just be a resonant frequency in your exhaust at that rpm.

It's possible it's a resonance frequency because of the long tube headers but who knows. I'll try seeing if there's any play in the crank pulley but you would hear it at idle while revving If there were.

1slow370 · 01-21-2011, 03:39 AM

my money is on resonance the aftermarket exhausts are stiffer and not dampened as well as the factory ones so they tend to make these funny resonances sometimes. A lot of times it helps to just loosen them up and tighten them back down to let the pipes move and do their thing from the heat stresses.

Daishi · 01-21-2011, 07:11 AM

Quote:

Originally Posted by 1slow370

my money is on resonance the aftermarket exhausts are stiffer and not dampened as well as the factory ones so they tend to make these funny resonances sometimes. A lot of times it helps to just loosen them up and tighten them back down to let the pipes move and do their thing from the heat stresses.

Sounds good. Ill leave it the way it is and if it starts getting loud or anything Ill keep you guys posted on what happens. Right now its something thats only really noticeable to the driver who daily drives the car. Its not very loud and you have to listen for it and know when its coming.

01-21-2011, 03:39 AM	#2 (permalink)
1slow370 A True Z Fanatic Join Date: Aug 2009 Location: In the D Posts: 3,732 Drives: v8 74 260z ;) Rep Power: 7251	my money is on resonance the aftermarket exhausts are stiffer and not dampened as well as the factory ones so they tend to make these funny resonances sometimes. A lot of times it helps to just loosen them up and tighten them back down to let the pipes move and do their thing from the heat stresses. __________________ ANSWER PRICE LIST Answers - - - - - - - - - - - - - - - - $0.75 Answers (requiring thought) - - - - $1.25 Answers (correct) - - - - - - - - - - $12.50

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