2G Crank pulley vibration

[2fast2evo]

Hi all, I'm just looking for some advice regarding my crank pulley. I have a fresh internal rebuild on my 7-bolt (I'll update my profile soon) and I reused my old harmonic damper/crank pulley among some other stuff. I noticed a *slight*, almost imperceptible, squeaking noise from the driver side (OK...passenger side for me but RHD problems) that was not coming from the accessory belts, in time with the engine RPM. At idle with the hood propped, I also noticed that the crank pulley was vibrating maybe +/-1 mm out of plane. I have no AC so there is no counter-tension on the backside of the pulley. Should I consider this amount of movement as acceptable or should I replace the damper? Is the movement probably just because of the lack of an AC belt? And is the noise possibly related? Any inputs are welcome, thanks.

 

[pauleyman]

No it's not acceptable. Replace the balancer.

 

[2fast2evo]

Thanks, I didn't think it was good but I hate to throw money at parts and solve nothing.

 

[pauleyman]

Balancers should not wobble

 

[gofer]

A DSM buddy had this same "wobble" on his crank pulley so he replaced it with a harmonic damper Fluidampr and it didn't go way. He pulled the crank pulley and started the car and the wobble was still there on the crank sprocket, it looked like the crank was wobbling.

The problem ended up being a damaged crank sprocket and key way.

It could also be the crank pulley though, especially if it's stock and the rubber is old and cracked. I'd start investigating the issue though instead of living with the squeak...

 

[2fast2evo]

I guess I'm not driving it any further or running it until I change the pulley. I just wasn't sure whether or not it required IMMEDIATE attention, although as was said it is a balancer and balancers shouldn't be unbalanced. I read a bit more about some horror stories of balancer shrapnel getting caught in the timing belt so I will wait on this one and update once I have changed things out.

 

[2fast2evo]

Just to follow up on this, the noise was definitely the harmonic damper vibrating. I replaced it with a new one and she is running great now.