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Noisy Belt.... How To Fix?

BSK

By BSK,
in General Maintenance

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BSK Enthusiast

BSK

Posted
Posted

i got a noisy drive belt that only seems to whine at idle when it drops between 770-790rpm.

how the hell do i fix it????

all the belts are only 8000km old... i've been told to rub dry soap on it to let it slip a little which helps for about 20min then the whine comes back.

suggestions please?

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https://www.sau.com.au/forums/topic/116546-noisy-belt-how-to-fix/
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chrissso Proficient

chrissso

Posted
Posted

Hey BSK.

Can you give us more info?

When you said all belts, is that all fan belts AND the timing belt?

How many km on the clock?

Timing belts can be noisy if old, or aftermarket. Bit of a whiney noise

Could be bearings ^. They sound like a metalic whiring noise.

BSK Enthusiast

BSK

Posted
  • Author
Posted (edited)
Hey BSK.

Can you give us more info?

When you said all belts, is that all fan belts AND the timing belt?

How many km on the clock?

Timing belts can be noisy if old, or aftermarket. Bit of a whiney noise

Could be bearings ^. They sound like a metalic whiring noise.

yep all belts were changed 8000km ago including timing belt. the timing belt is a gates belt. currently at 104 000km

the sound is like a goat trying to hum while being choked, not really a metalic scrapey sound..... not loud but annoying and like above only when im stopped at the lights/drive thru and the idle drops.

a pulley bearing maybe?? is there some kind of spray lube i could use?

sorta hard to tell exactly which belt cos i cant isolate the sound with the fan right in my face.

Edited by BSK
RaseR Collaborator

RaseR

Posted
Posted

Hi BSK,

I've got the exact same noise, I believe in my case it's either the timing belt (brand unknown) or the idler/tensioner bearings (more likely)....I used the 'screwdriver stethoscope' method to pinpoint where the whirring was coming from, put the head of a large flat head screw driver firmly against the timing case cover and listened thru the handle, I could hear the noise clear as a bell.....just be careful if you try, there's lots of stuff spinning on the front of the motor! :/

RANDY Veteran

RANDY

Posted
Posted

If it's a squeal, tighten the belt.

If it's not squeeling, but sounds nasty, try loosening it a bit? My belts were noisy when I overtightened them.

Otherwise yeah, I replaced my idler and tensioner. Not a bad idea, but playing with the belts a bit cheaper and quicker to test this theory.

R33S2 Grand Master

R33S2

Posted
Posted

If the noise stopped when you put the soap on it ,I would tighten the belt a bit, if you can move the belt more than its thickness its loose but make sure you have some movement, if the noise is still there try the soap again.

Why soap works is a bit of a mystery to me, as it is made up of part oil/fat and part acid, maybe it cleans the belt and pulleys and squealing is a result of the belt slipping on the pulleys, but hold it there long enough on both sides and the squeal goes away, well it has for me anyway.

Benno31 Experienced

Benno31

Posted
Posted

You can buy belt quietener, CRC make it.

I have the same problem and the belt quietener spray worked for 5 mins. It isn't worth it in my personal experience.

I am about to remove all the belts and degrease the belts and the pulleys and then refit.

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