Harmonic Balancer/Crank pully wobbling?

[Vendor Defendor]

i am probably halluncating, but... it never hurts to ask. i have a knock some where in my car. i am 92% positive its not rod knock, but i thought it was coming from the valve train. but, looking at my harmonic balancer the other day, it appeared to be wobbling... could this cause a knocking sound?


thanks

 

[Nick Micale]

YES, it can cause a knocking sound.

It can also cause a crank to be trashed.

I would remove the balancer ASAP and check it closely. The snout of the crank may be damaged, and it is very hard to tell with the timing cover in place.

 

[SPOOLN]

Crank Walking

I would check the bolts on the balancer and pully, if they have ever been removed they may have backed off. Also check you crank sensor to see if it is touching the balancer ring. You could pull the crank balancer in or out to see if the is a lot of clearance for the thrust bearings.
Hope this helps,
Tom

 

[turbofish38]

The only time I experienced a wobbling balancer it was the main bearings going on their way out. I didn't catch it in time and ended up trashing the block and crank. I must have put a couple of hundred miles on the engine before it got really noticable. Does your belt tensioner bob all the time too? The strange thing is it didn't make a whole lot of noise in the beginning, kind of sounded like a cam sensor ticking or a valve lifter not pumping up.

Eric Fisher

 

[Vendor Defendor]

ach, this dosent sound to happy, but no the belt tensioner is not wobbling, everone that hears the noise saiys it sound like a lifter.

i changed the rear main seal about 4 months ago, and my rear main bearing looked just fine. and i have decent oil pressure... i have 75psi at start up, and for about the first 5 or ten miles, then it dies down to about 27psi at idle. at WOT it gets to the 75 area too....

 

[JeffG]

That's pretty damn interesting. Mine wobbled too, and then the tensioner started to bounce around and make noise. That happend right abound the time oil pressure started to slide south. Pulled the motor and found the two rear main bearings were done. The not so funny thing is that the new motor I have in there now is starting to do the same thing....Ackkkk

 

[ThikStik]

My lt-1 Caprice motor's damper has a wobbly motion but no sound to it. Its done it the whole 144k miles ive had it . Motor has 216k total miles. Ive always been worried about it. I know the Buick 109 doesnt have a rubber isolater in damper. So the outer part cant seperate. Ive seen a loose crank bolt cause a damper to fracture, and get noisy, yet still stay together on crank.
Good Luck

 

[turbojimmy]

Originally posted by Vendor Defendor
ach, this dosent sound to happy, but no the belt tensioner is not wobbling, everone that hears the noise saiys it sound like a lifter.

i changed the rear main seal about 4 months ago, and my rear main bearing looked just fine. and i have decent oil pressure... i have 75psi at start up, and for about the first 5 or ten miles, then it dies down to about 27psi at idle. at WOT it gets to the 75 area too....

No, that's not good at all. My oil pressure was fine when mine started doing that. Actually, it was fine right up 'til we had to take the motor back out.

I had a *slight* knock and noticed the same thing - wobbling crank pulley. I went through all of the above. Checked the balancer big bolt and pulley bolts. Like a fool, I even replaced the balancer with a nice new GM one. Of course the problem was the entire crankshaft moving around and the knocking was the crank against the back of the block. My thrust and mains were wiped out.

You can minimize damage by not running it anymore....sorry to say.

Jim