99 E300TD alternator problems
 

I had the charge battery light come on .Like others here while running there is a clicking noise from the alternator and a bump of the belt tensinor once in a while when the alt trys to charge . I removed the brushes found that they were not all the way worn down but did not have much travel left untill they would not be touching .Order new voltage regulator brush assmbly.This fixed the problem old brushes were worn about a 1/4 of a inch.It is iteresting that the diesel is the only car that I could find a voltage regulator brush assmbly for.

How many miles on your car? I might pull mine out and check them.

Hi

It might be that there is nothing wrong with your alternator, it could be the pulley on the front of the alternator. The pulley is a free wheeling pulley and it is intermittently free wheeling in both direstions causing your problem.

This is a common problem you need a new pulley but special tool required to change it.


"Pulley (freewheel) – P/N 611 155 0415

Pulley socket tool – P/N 602 589 00 10 00 (serrated wrench 17 x 20 mm DIN 5481 / waf 17 mm)

You can buy the socket tool from from MB Dealer (it's about £27) or you can get them to do the job which I believe is about £120. Apparently the job can be done with the alternator in situ, a hex key can be inserted in the end of the shaft to hold it stationary while the pulley is removed using the socket. Mine has seized also and I am about to replace it, but it looks as though the hex slot in the end of my shaft has been butchered (previous MB workshop ???) so I have no way of holding the shaft stationary. I may just remove the alternator and disassemble so that I can hold the stator by hand while removing the pulley."


Good luck

McCool300TD

Our car has 117k on it .Wife just called and said battery chagre light is coming on again. I had looked it that pulley I can see that the alt is spinning.It worked for a couple of days. I will have to check it when she gets home.

I replaced my tensioner shock and spring earlier this year. Prior to that I would occaisonally get a warning light but now it has been 6+ months without one. Also, there was a small coolant leak from the t-stat housing that might have caused the belt to slip too, fixed that at the same time...don't forget the little stuff like friction on the belt. My light would only come on at startup, when the GPs are drawing most current and the engine is idling...

Hi

When mine was paying up there was a slight squeaking noise from the pulley and it worked intermittently. Watch the pulley at tick over if there is end play in it and any noise from it it is shot.

McCool300TD

The winner is McCool300td
 

I took out the alt and found that I could get pully clutch to slip going in the drive direction for about a 1/4 of a turn.pop the seal off and used a hot glue gun to glue the shaft to the pulley .Just to give it a liitle extra holding power to see if that fixed it,it did .pulled alt back off removed glue, and sprayed some brake clean into clutch and was able to flush out a lot of rust.It now free wheels better and I was no longer able to get it to slip.It does have end play so I am going to replace it but for now it seems to be working.Drove it last night for couple of hours and all was okay.

Hi

Great job, i had asked the guy who changed my pulley if it was possible to weld the pulley to stop it slipping but he said they had tried it but with limited success.

Glad i was of help.

McCool300TD

I went and priced a pulley today dealer wants $134 for it .Any ideas on a source that would be cheaper? I looked around on the net yesterday but could not find one listed.