belt squeaks and belt dressings - PeachParts Mercedes-Benz Forum

JHZR2 · #1 03-03-2004, 10:57 PM

Hi,

At startup, sometimes I get a squeak from under the hood. It seems to be coming from one of the belts.

I run OEM mercedes belts, installed by the dealer about 50k (2 years) ago. They all look fine, no cracks, etc.

I am curious if a squeaky belt is anything to worry about? I see they sell belt dressings which are supposed to quiet and protect belts. Is this reccomended?

If the squeak is actually a pulley, am I in for trouble? I have no issues with the car temperature (needle always stays just a hair above 80, just in the correct spot), but I worry about if the waterpump would ever go. Alternator, power steering, ac I can do without... But when Im on a long drive 1000mi from home, I cant loose my waterpump. Any suggestions on how to check its pulley, or the pump itself?

Thanks for your help,

JMH

BoostnBenz · #2 03-03-2004, 11:26 PM

All belt dressings do is soften the rubber which shortens the life of it, I wouldn't recommend using one unless you plan on replacing the belts soon anyways. There are two belts on the alternator/water pump so odds are both won't go at once but if it slips to much the car may start running warmer. While MB has a special tool for the belt tension I'd just feel it and if it felt to loose I'd run the tensioner in a bit further. Be careful on the alternator tensioner, they seem quite easy to break.

240-diesel · #3 03-04-2004, 10:06 AM

My 83 had a belt squeek for a couple of weeks, It would happen every other day.
I sprayed a little wd40 on it just to find out which belt it was.
Just spray a small amount while you raise the idle and go from there.
My Alt belt was a little loose and that was it.
Good luck.

leathermang · #4 03-04-2004, 10:12 AM

This is an easy fix.....
Here is the rule....
Change the hoses and belts every two years...
Anything else is just window dressing ( or belt dressing ) and is temporary at best.... not something to trust with the temperature of your engine on a regular basis...

BoostnBenz · #5 03-04-2004, 10:24 AM

I think changing the hoses every two years is quite excessive, maybe it is because I've never had one fail on me but I try to change them every 8yrs or so. I'd say that every few years for the belts aren't that unreasonable though.

JHZR2 · #6 03-04-2004, 01:03 PM

2 years?!?

I guess it depends on the manufacturer. My father still has the original belts on his 94 toyota previa. Thats after 165k! He gets it all done at the dealer, and youd figure theyd love to sell belts. But they check and every time they tell him theyre ok.

Hed have the original hoses as well if the plastic radiator hadnt cracked.

Ive read somewhere that MB hoses are known to go 30 years! I dont think Id push that, but do you really do your belts and hoses every 2 years?

I have the original hoses in my 98 chevy, but the serpentine belt was replaced last winter as it showed signs of cracking.

JMH

Jassper · #7 03-04-2004, 03:00 PM

If your belts squeek take a piece of soap and hold it against the belt from underneath lightly when the engine is running. The squeek will go away. I am not sure how much this will help the general condition of the belts yet the squeek will certainly go away.

If your belts squeek after starting the engine in winter it may just be that your accumulator is discharged. When you start, the alternator has to overcome more resistance to charge a discharged accumulator at startup which can cause the belts slip and squeek.

JHZR2 · #8 03-04-2004, 03:05 PM

That is the most usual situation. They dont squeak much if at all in warmer weather.

Thanks,

JMH

84300DT · #9 03-04-2004, 07:41 PM

most likely - alt belt or a/c belt - both of mine were loose a bit and would squeal like a dying pig..
tightened 'em up and no more squeaks.

agree belt dressing could deteriorate the rubber and be only a 'temporary' fix to an otherwise easy permanent remedy.

BoostnBenz · #10 03-04-2004, 09:31 PM

Since it came up again inorder to properly use the tensioner on the alternator/water pump belts you should loosen the two pinch bolts on the alternator first, and then tighten with the tensioner, retighten the pinch bolts and go another half turn on the tensioner to bind it enough so it doesn't come loose again.