Need help with Harmonic Balancer noise

jreask

Member
It rained here in Missouri pretty heavily over the weekend. When I got in my 2002 4Runner after I started it I heard a harsh sound coming from the water pump/fan bracket area. It only lasted a couple of seconds. The timing belt/water pump was done by the PO about 12K miles ago. I stopped and got gas and when I started it I got the same grinding sound. When I got home 10 miles later I started it and no more noise when starting. Today I decided to do a little checking. I sprayed water with a squirt bottle near the fan pulley but no noise when starting. Then I sprayed water near the crank pulley/harmonic balancer and this is when the noise happens. Here is a short video.
<iframe width="560" height="315" src="https://www.youtube.com/embed/x_EpJTfgUmM" frameborder="0" allowfullscreen></iframe>
I hope I did this right. Don't pay any attention to the video, it's the noise you need to hear.
You can hear the grind at about the 4-6 second mark. What do you guys think about the noise? Should I tear it down to check the pulley and balancer ? Thanks for your help.

Joe
 
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It sounds to me if a drive belt may not be grabbing initially. The belt may be too waterlogged to be completely dry yet. I'd also take a good look at the pulleys. If you have to, remove a belt and it start it again.

I'd then check the torque on the HB bolt.

If there was a problem with the key way or the like you should be able to see such in the HB while the engine is running....
 
It sounds to me if a drive belt may not be grabbing initially. The belt may be too waterlogged to be completely dry yet. I'd also take a good look at the pulleys. If you have to, remove a belt and it start it again.

I'd then check the torque on the HB bolt.

If there was a problem with the key way or the like you should be able to see such in the HB while the engine is running....

Thanks for your input. When I spray water around the fan pulley/waterpump I get no sounds at all. It's when the rear or back side of the HB gets wet when the grinding sound is. Does it sound like a belt slipping or something else?
 
Take off all the drive belts and start the engine. See whether you hear that sound again. It could be harmonic balancer touching the timing belt cover. Any rubbing anywhere?
 
Take off all the drive belts and start the engine. See whether you hear that sound again. It could be harmonic balancer touching the timing belt cover. Any rubbing anywhere?

It only touches when it's wet? Sounds like it's under the cover.
 
Then if you have a gut feeling it is under the cover then I guess you know what has to happen.

Maybe the little circular piece that fits on the snout of the crank was put on backwards, though I cannot see how that would cause the sound.

I'd still at least see if the crank bolt is at 217ft/lbs....
 
Then if you have a gut feeling it is under the cover then I guess you know what has to happen.

Maybe the little circular piece that fits on the snout of the crank was put on backwards, though I cannot see how that would cause the sound.

I'd still at least see if the crank bolt is at 217ft/lbs....
Do you think that it is possible that the inner circle of rubber is possibly slipping ? That is what it sounds like. If so, how do I know? Do you know the distance from the top of the keyway to the timing mark? I won't be able to tear it down until Thursday. Just wondering if that is what the rough grind sound was in the video?
 
It sounds like an outer belt to me. I would take off the outer belts and see if that gives you a clue. If that doesn't yield a result, then taking off the top timing cover and looking inside to see if the timing belt got wet. If it did, you will need to replace it. The covers are not completely waterproof.

I also agree that checking the crank pulley bolt torque is a good idea.
 
I'll put two marks on the inner and outer parts of the HB. if they line up after a drive it would appear that the inner rubber part is not slipping.
 
I'd still say like Stir Fry Boy believes that it is an outer belt. If a belt got really water logged it could be days before it drys out.

I have had control arm bushings make all kinds of noise after getting them soaked. Once they dry no more sounds. Instead of being a bushing it sounds like a belt.
 
It sounds to me if a drive belt may not be grabbing initially. The belt may be too waterlogged to be completely dry yet. I'd also take a good look at the pulleys. If you have to, remove a belt and it start it again.

I'd then check the torque on the HB bolt.

If there was a problem with the key way or the like you should be able to see such in the HB while the engine is running....
You are absolutely correct. I took the belts off one at a time and of course, the last one, the alternator belt was the culprit. When I looked at it off of the truck, it was egg shaped. I guess I better get a new one over the weekend. Thanks to everyone for the input and help. I did torque the crank bolt also, it was nearly impossible to get to 217 but when I heard the wrench click it was a big relief. You almost have to stand on the wrench to get 217 foot pounds.

Joe
 

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