[manikjeet]

This is called setting the Duty Cycle and should never be tampered with. The settings are not common to every engine.

[sportz_kruzer]

Originally Posted by Viraat13

This is the EZL setting which is tuned by a Bosch engineer before every car leaves the factory floor. The setting is NOT TO BE CHANGED. Each EZL matches with the specific engine. I see remains of the wire seal which has broken.

EDIT — It is called something else in the E220, HFM something or the other. It's called EZL in the pre 1992 vehicles, but either way, it isn't meant to be adjusted in these cars. The pre 1992 cars on the other hand, are adjustable according to the kind of fuel you are using.

Oh well it was me who removed it to see what the deal was. Luckily better sense prevailed and I put it back as it without tinkering with it. This was long long ago. I was always curious to find out if I could extract some more performance by tinkering with it..but guess not!

[DeepakMenon]

Originally Posted by sportz_kruzer

Oh well it was me who removed it to see what the deal was. Luckily better sense prevailed and I put it back as it without tinkering with it. This was long long ago. I was always curious to find out if I could extract some more performance by tinkering with it..but guess not!

What I have read is that its for advancing retarding timing to account for fuel quality

[sportz_kruzer]

Ok..I am having this (serpentine) belt squeal issue which just won't go...

The issue: belt makes noise and squeal s at startup only when cold. Goes away say after 10 mins.

Belt : new belt . Make - contitech. The same type n make which was there before. And before there was no noise whatsoever on the older belt. Replaced it coz of signs of aging such as cracking n stuff.

Things tried: the noise goes away in an instant when I apply a little brake fluid on the running belt using a cloth wetted with dot4 brake fluid. While the car is idling and belt is chirping n squealing I touch the innards of the belt with cloth dipped in brake fluid. I do this on the belt running in the space between the ps pump amd compressor (inner side) the noise instantly vanishes. .only to come back the next day!

I also removed the belt..sandpapered each grove of each and every pulley. Was surprised to find lots of sticky rubbery stuff probably from the old belt. Now the noise changes to more of a squeal than a chirp. The aound as far as I can make out distinctly comes from the alternator pulley. I checked for free movement. The alternator spins freely n smoothly. .no groans or grumbles

Tried adding tension using a box spanner and pulling the tensioner to the right yo add more tension to the belt .guess what..the noise increases!

Only brake fluid instantly solved the problem albeit only temporarily.

Any clues what's going on here?

[msaudf]

I've heard a slight dusting with chalk powder resolves belt squeal, as it essentially originates due to slippage and chalk powder gives it some traction.
I haven't tried it ever so please be cautious.

I also think that brake fluid could damage the belt.

Or you could try another belt all together because maybe this new one you just got could have come out of a bad batch and has some problems with the rubber compound.
I realize the reason you are seeking opinions here is so that you may retain the new belt, but a spare one in your boot wouldn't hurt .

[sportz_kruzer]

Originally Posted by sportz_kruzer

Ok..I am having this (serpentine) belt squeal issue which just won't go...

The issue: belt makes noise and squeal s at startup only when cold. Goes away say after 10 mins.

Belt : new belt . Make - contitech. The same type n make which was there before. And before there was no noise whatsoever on the older belt. Replaced it coz of signs of aging such as cracking n stuff.

Things tried: the noise goes away in an instant when I apply a little brake fluid on the running belt using a cloth wetted with dot4 brake fluid. While the car is idling and belt is chirping n squealing I touch the innards of the belt with cloth dipped in brake fluid. I do this on the belt running in the space between the ps pump amd compressor (inner side) the noise instantly vanishes. .only to come back the next day!

I also removed the belt..sandpapered each grove of each and every pulley. Was surprised to find lots of sticky rubbery stuff probably from the old belt. Now the noise changes to more of a squeal than a chirp. The aound as far as I can make out distinctly comes from the alternator pulley. I checked for free movement. The alternator spins freely n smoothly. .no groans or grumbles

Tried adding tension using a box spanner and pulling the tensioner to the right yo add more tension to the belt .guess what..the noise increases!

Only brake fluid instantly solved the problem albeit only temporarily.

Any clues what's going on here?

Well I also tried talcum powder. ..liberally spreading it in the groves on the belt. ..things were good...for 2 days :-(

Can you suggest me any other brands? Dont know if Fenner produces these belts. My "lesser" cars generally use these belts (no offense) :-)

[DeepakMenon]

Originally Posted by sportz_kruzer

Ok..I am having this (serpentine) belt squeal issue which just won't go...

The issue: belt makes noise and squeal s at startup only when cold. Goes away say after 10 mins.

Belt : new belt . Make - contitech. The same type n make which was there before. And before there was no noise whatsoever on the older belt. Replaced it coz of signs of aging such as cracking n stuff.

Things tried: the noise goes away in an instant when I apply a little brake fluid on the running belt using a cloth wetted with dot4 brake fluid. While the car is idling and belt is chirping n squealing I touch the innards of the belt with cloth dipped in brake fluid. I do this on the belt running in the space between the ps pump amd compressor (inner side) the noise instantly vanishes. .only to come back the next day!

I also removed the belt..sandpapered each grove of each and every pulley. Was surprised to find lots of sticky rubbery stuff probably from the old belt. Now the noise changes to more of a squeal than a chirp. The aound as far as I can make out distinctly comes from the alternator pulley. I checked for free movement. The alternator spins freely n smoothly. .no groans or grumbles

Tried adding tension using a box spanner and pulling the tensioner to the right yo add more tension to the belt .guess what..the noise increases!

Only brake fluid instantly solved the problem albeit only temporarily.

Any clues what's going on here?

Ok here are few questions you need to answer

when new belt was put; how was the tensioner made loose?
Is the tensioner back to its proper setting?
New belt does not need any chalk, talcum powder or momma's love; it is a new belt

now if belt is still slipping, check the pulley on the tensioner if it has play
Check the strut on the tensioner, if it goes it shows on the belt


I am 80% sure you need the following [I just changed mine]; if ignored it will break one day and you will be stranded
- New Tensioner
- New Pulley
- New Strut


Note: nothing wrong with the brand of the belt; I have been using that for 2-3 years; replaced like for like; No issues

[Aroy]

The squealing of any belt is due to slippage. That can be either due to poor adhesion or due to loose belt.
. If it is adhesion, then clean all the pulleys in its path so that there is no oil or dirt residue. Clean the belt also.
. If the belt is loose, check the tension. From the workshop manual you will get both the tension and the "give" of the belt at its longest stretch.

[DeepakMenon]

Originally Posted by Aroy

The squealing of any belt is due to slippage. That can be either due to poor adhesion or due to loose belt.
. If it is adhesion, then clean all the pulleys in its path so that there is no oil or dirt residue. Clean the belt also.
. If the belt is loose, check the tension. From the workshop manual you will get both the tension and the "give" of the belt at its longest stretch.

In a W124 you have hydraulic tensioner which manages the tension;

Sportz_kruzer read through this manual for some basic idea

[sportz_kruzer]

Originally Posted by DeepakMenon

Ok here are few questions you need to answer

when new belt was put; how was the tensioner made loose?
Is the tensioner back to its proper setting?
New belt does not need any chalk, talcum powder or momma's love; it is a new belt

now if belt is still slipping, check the pulley on the tensioner if it has play
Check the strut on the tensioner, if it goes it shows on the belt


I am 80% sure you need the following [I just changed mine]; if ignored it will break one day and you will be stranded
- New Tensioner
- New Pulley
- New Strut


Note: nothing wrong with the brand of the belt; I have been using that for 2-3 years; replaced like for like; No issues

1. Belt was changed two months ago. Issue started say 3 weeks ago. After belt change. .the car was idle for a month.

2. I fit the belt myself. I used a box spanner on the tensioner pulley bolt and pushed it leftward to release tension on the belt. Removed the old one and put in the new one. Lost my way in the process..consulted the belt path diagram for e220 and managed to install the new belt. Groove on groove the belt sits snug on all pulleys. Triple checked!

Tensioner pulley puts enough tension in the sense u can vaguely compare the force used to push it to left for loosening with say lifting a 5-7 kg dumbell.

Can you please clarify the following from ur post:

1. Is the tensioner back to its proper setting?

I released tension on the pulley via the box spanner ...the pulley goes right ..puts tension on the belt. and thats it! Iam I missing something. ?

2. Ref play on tensioner. ..can u elaborate? The strut is stout enough. ..pulley spins freely with the belt off and no lateral play on its bearings. Didn't find play anywhere.

I even tried adding more tension on the belt by pushing the tensioner towards right (using box spanner) thus stretching the belt..all while the engine was running. ..and the noise would increase! !

3. Lastly I have a pulley and a strut..where is the tensioner? ? Isnt the pulley strut combo called the tensioner itself? (Sorry if its a dumb question)

[DeepakMenon]

Based on what you wrote; it was installed in the right manner; now since it was done few months back and it was all smooth I would not worry about belt

now check this, this squeaking you hear of can be of the following couple of reasons

1. Your tensioner strut, it will give play to the belt which will make the belt squeal
2. your belt getting contaminated; mostly due to coolant; do you see loss of coolant? if yes check water pump side; this will effect in cold; after a while the belt warms and can manage the drip and not slip
3. your alternator till warmed up can give you these high pitch noises; Very rare; but worth a check


My bet is on the strut, they may seem hard and not leaking, but if you a new one lying around; try replacing

lastly on your question of tensioner, below is the pic of mine when it gave up on me, symptoms.. makes light rattle and then it is a ticking bomb, I ignored and it broke on me;

all parts are different if you buy from MB

Pulley : A1112000070
Tensioner : A1112000770
Strut: A1112000414



Point to Note; If you belt is slipping so much in cold; I am sure your AC compressor might not be kicking in as it senses a slip and shuts down

[sportz_kruzer]

Yes!! Mine does rattle lightly too.. a wee bit of jump in pulley say 1mm +- also I specifically checked for coolant leak -none. I turned on the ac full blast and turned steering fully left n right. .with the headlights on high beam..fully loading the belt in every way. .but there is no change in sound and everything works the way it should. No loss of cooling or power assist..

That component is new to me. .will examine it today

[DeepakMenon]

Originally Posted by sportz_kruzer

Yes!! Mine does rattle lightly too.. a wee bit of jump in pulley say 1mm +- also I specifically checked for coolant leak -none. I turned on the ac full blast and turned steering fully left n right. .with the headlights on high beam..fully loading the belt in every way. .but there is no change in sound and everything works the way it should. No loss of cooling or power assist..

That component is new to me. .will examine it today

use a screwdriver to your ear and check if the rattle is from the pulley or tensioner itself;

they need a change every 100K; so if in doubt change it; coz when this goes you basically cant drive; you will need to be towed


if your AC compressor kicks then the slip is very slight; coz it has a speed sensor which cuts it off if the belt is slipping too much

[sportz_kruzer]

Originally Posted by DeepakMenon

I am 80% sure you need the following [I just changed mine]; if ignored it will break one day and you will be stranded
- New Tensioner
- New Pulley
- New Strut

What exactly happened in your case? Did the belt slip off coz the pulley lost its alignment?

[DeepakMenon]

Originally Posted by sportz_kruzer

What exactly happened in your case? Did the belt slip off coz the pulley lost its alignment?

it started making small noises; I thought will do it in a week or so when free; i think the bearing in the pulley gave away at 40 kmph; twisting the belt and leaving me stranded few km from home

the culprit in my mind was the pulley which slipped took the belt with it damaged the tensioner

as a safety i replaced all;


So in my list of things that can strand u in a W124 this got added
1. Fuel pipe near fuel pump
2. Belt tensioner
3. flexi shaft bushes

all the three are service item; and they need to be changed as they go without much notice [mostly shakes, rattle]