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bad harmonic dampner?

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socal97gst

Probationary Member
7
2
Mar 22, 2019
lancaster ca, California
hi i just bought my first dsm after having a horrible gts 3rd gen ecljpse....i am doing all the maintenance before getting go fast parts....oil and filter plugs,wires,cleaning throttle body and a battery....along with worn suspension parts....i have a horrible belt squeal upon start up ive tried tightenung all alternator bolts and adjusting the alternator tension...i think i may have a bad dampner however i dont see much wobble when car is running...here is a pic
 
Hey there, and congrats on your first (proper) DSM!

Pic didn't go through, so maybe try again. The Harmonic Damper (Balancer) is rarely the cause of a squeal. The most common cause of squealing belts is if they are too worn. Followed by improper tightness setting, and lastly but rarely, bent/crooked pulleys.

Just today I finally managed to fix a long-time squeal on mine, after I had replaced both pulleys and harmonic balancer (it had other issues).

What I found was that the power steering pulley had really sharp V-shaped grooves. Almost knife sharp. It caused my ~10,000 mile belt to get very deformed and it ate away most of the rubber material. I kept having this annoying squeal sound regardless of cold/hot. I swapped the belt out and the squeal went away, but it will ruin the belt much more quickly because the pulley itself is bad.

So in your case, I suggest you first locate exactly which belt the squeal is coming from (use drops of water on each belt until the squeal stops), then inspect it. If the grooves are really sharp and perfectly V-shaped, the belt is too worn and you should look at the pulleys too. For reference, a new belt has grooves which look almost trapezoidal and flat on the top.
 
ahh thank you i will try the water trick let ill try and post the dampner pic
 
I agree, there could be other items to check before the balancer first.

If you are looking to test the harmonic balancer, the failure point is typically the rubber section that bond the inner and outer portions together. If there is no clear sign of failure, a quick test to determine if the inner and outer sections are moving independently (rubber section failing), you can use a paint or grease pen to mark a line that intersects both parts of the balancer. If either portion of the line misaligne after a drive (under load) , then you need to replace it.
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I have had a belt squeal from a bad harmonic dampener, it looked fine but the squeal was the dampener slipping inside itself.
 
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