Ever since I had the belt tensioning system replaced, the belt has been extremely noisy and the sound comes and goes... It mostly squeaks when the engine is cold and I've noticed that sometimes pushing "0" on the CCU will make it stop sometimes. Sometimes the squeal is brought on by applying the brakes... and if it still squeals when I jump on the interstate at speeds of 55-65 it almost overheats until the belt stops squealing...

Any ideas or suggestions are highly appreciated!

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BLUE BEAST

Thanks for advice, replys, and suggestions!

1987 300SDL Turbo 308,000 miles
"seen better days"

Are you sure it's the belt and not the alternator?

Get a candle and run it against the edge of the belt while running (carefully). See if the noise level changes. You only need a touch.

I'm not optimistic that this is your issue because the serp belts don't squeal like the traditional v-belts.

Can't you take it back to wherever you had it done?

Sixto
87 300D

I had the identical problem, after the alternator went bad, I replaced the belt at the same time. Original belt had polyester reinforcing thread, I upgraded the belt with a metal reinforcing thread. Car did not like the metal reinforced belt. After two weeks I replaced the belt with the cheaper poylester reinforcing, problem gone instantly.








'91 350SD 532,000
'94 SL500 44,000
'87 300SDL 236,000

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jcciem
'94 SL5000 60,000
'91 350SDL 545,000
'91 350SD 197,000
'00 E55 AMG 77,000

When the mechanic (1 hour away) replaced the tensioning system he claims he got oil all over the belt and thats why it was squeaking... Would the alternator cause the engine to slightly overheat if the slipping continued on the interstate?

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BLUE BEAST

Thanks for advice, replys, and suggestions!

1987 300SDL Turbo 308,000 miles
"seen better days"

........got yourself a real genius there........hey.......

Is this the same moron who tried to remove your ignition with a hole saw?

He screwed something up, better figure it out before the belt lets go. Take some pictures maybe we can see something odvious.

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1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

Did he put it back on correctly? There is no diagram under the hood and you could put the belt on another way - but that would make the belt squeel.

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BENZ THERE DONE THAThttp://www.peachparts.com/shopforum/...c/progress.gif
15 VW Passat TDI
00 E420
98 E300 DT
97 E420 Donor Car - NEED PARTS? PM ME!
97 S500
97 E300D
86 Holden Jackaroo Turbo D
86 300SDL
(o\|/o)

I think that you're about 1/2" short if you try it the "wrong" way. One member struggled for days with the wrong path...........no go.

A failing alternator should not cause an overheat, but a failing water pump can.

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RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

91 W124 300D Turbo replaced, Pressure W/G actuator installed. 210K

90 Dodge D250 5.9 Cummins/5 speed. 400K

RRGRASSI is Right!

And your "Shadetree" is Wrong.

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'84 300SD sold
124.128

There is no performance loss or anything different except for the annoying squeal... which comes and goes. Sometimes it only squeals at idle or if I put my foot on the brake, mostly when the engine is cold. If the squeal continues by the time I hit the interstate the engine begins to overheat, came really close the other night to pulling over, the temp got up to 110C and I almost gave up, but the second it stopped squealing the temp dropped down to normal 60-90C. He said he would put a new belt on for free if I buy the belt... not the same guy as before, other guy had more knowledge than this new guy... somewhat...

__________________

BLUE BEAST

Thanks for advice, replys, and suggestions!

1987 300SDL Turbo 308,000 miles
"seen better days"

Yikes! you live dangerously! Whatever it is, its only one of four things:
1. idler pulley (not likely) 2. Water pump 3. Alternator, and 4. A/C compressor
Those are the only places the belt feeds power. If its the idler pulley it would be squeeling constantly. I can't imaging the water pump binding intermittently so that leaves an alternator shorting intermittently and dragging on the belt or the AC is bad and somehow the clutch is getting activated possible only if you pressed AC button "on".
Whatever, its going to cost you big time if you crack the head from momentary overheating.
You need to find a good mechanic before the engine is toast!

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'95 E320 Wagon my favorite road car. '99 E300D wolf in sheeps body, '87 300D Sportline suspension, '79 300TD w/ 617.952 engine at 367,750 and counting!

You really should fix it before you blow it up. That red mark on the temp guage isn't kidding. Get into red and you will be replacing the head.

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1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

Are you sure the belt is routed properly? It is possible to install it so only a little bit of the belt touches the crank. New belts are very very easy to install, and readily available because the 6 cyl uses the same belt as the GM 3.8 V6.

You could also look to see if the belt is oily, and if it is clean it off. The whole belt would have to be slipping to make the water pump slip... the water pump really doesn't have that much drag. Also, when the belt slips it should shut your aircon off unless someone has modified the climate control system...

-Jason

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1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.