W202 C180 Alternator problem?

[cheesefish]

Hi Everyone,

I've been reading a few posts and think that I need a new alternator or diode pack but I just want to make sure first from you guys.

I was using my 1996 W202 with no problems, then I got into the car the next day and the battery light came on. I did the usual spray of WD40 and fiddled with the wires on the back and nothing happened. I revved the car and it went off...happy days I thought, then it came on again. Yesterday same thing happened and it was fine for about 15 miles, then the light came on again. I managed to get it to an open stretch of road where I gave it some serious rev, upto 6000rpm and the light went off again for about 5 more miles, it's now on and seems to show no signs of going off.

The belt to me seems fine, but then someone else said it looked loose to them, I can twist it easily but there doesn't seem to be any stretch in it. The alternator I have is the Bosch 14v 45-90a 010 154 4602.

I've checked the points on the back and it was suggested that I check the earth, the only one I can see is a brown wire from the alternator upto the body, should there be another one somewhere?

Any advice would be greatly appreciated.

Cheers

Chris

 

[television]

If it is a Bosch,,just get the brush pack from any Bosch service center

http://www.detali.ru/cat/oem_mb2.as....418&VIN=*&CT=M&cat=19K&SID=15&SGR=030&SGN=02

 

[KOMPRESSIT]

Old post, but perhaps someone can help me.

W202 - engine cut out while driving a few nights ago. Jump start got it going until I got home. Charged battery then checked voltage - 11.8v doesn't change when engine running. To me this suggests the alternator Isn't producing any charge, but the puzzle is battery light on dash doesn't come on. Another issue I just noticed is the dash lights go out quicker than they used to when the ignition is turned on. They go out before I can start the car.

Apart from these two issues the car starts and drives OK.

Can the alternator be faulty when the battery light doesn't come on? (Comes on initially t hen goes out although more quickly).

Thanks for any help.

 

[television]

I would say brush pack, they can fail in many ways and only £20 ish

 

[KOMPRESSIT]

Thanks Television.
Checked underneath and removed the plastic cover from the alternator (the screws were so rusted I broke the 8mm screw the small wire was attached to). Hopefully will be able to sort it somehow.

On previous alternatives I've worked on - the brushes are easily removed,but this is a Valeo?alternator and couldn't locate the rectifier/brush pack. Any ideas ?

Do I need to remove the alternator? If so what do I use to rotate the tensioner - is it hex key or torque key ?

Also any ideas why the dash warning lights go out almost as soon as they light up ?

Apologies for3 different questions but at the moment I am stuck. Any help will be appreciated.

Thanks.

 

[KOMPRESSIT]

Hello, I checked the brushes and they are good.
The puzzle is the battery light doesn't come on even when turning the ignition on before starting the car. The other ignition lights come on for less than half a second and go out before turning the key to start the car. Very similar to this post -

http://forums.mercedesclub.org.uk/showthread.php?t=55247&page=2.

In summary - battery light doesn't come on at all, alternator produces no charge (brushes OK), other ignition lights flash on briefly when turning the key to position 1 all go out even before turning to position2. Disconnected alternator - same as above ( which would eliminate alternator electrics ?)

I'm beginning to think I might have two issues - alternator not producing any voltage & something causing an issue with the cluster lights including battery light.

Any suggestions / ideas would be much appreciated.

 

[bigasotonuk]

Hi,
If it was me I would initially be looking at checking the charging light in the cluster, and making sure the bulb hasn't blown. A misbehaving charging light is normally indicative of a failed or failing diode pack.

 

[KOMPRESSIT]

Hello bigasotonuk, thanks for your response. I should have added that I've already removed the cluster and checked the battery charge bulb and it is OK.

I'm thinking of trying a new regulator, but have searched the net and they seem pretty rare for the Valeo alternator. I wonder if I have an electrical fault that damaged both the cluster and the rectifier ?

Again any thoughts or suggestions are most welcome.