2001 C220cdi Intermittent Charging

[230K]

Hi

A work colleague has a 2001 c220 cdi and it let him down the other evening saying that battery low alternator npt charging etc etc.

He got towed to my house and i checked her out and sure enough wasn't charging.

I decided i would take the alternator off for him ( what a pain in the a$$ that was) and we took it to a local guy hoping that it was a regulator or whatever.

Turns out it is a Delphi alternator and apperently you can do very little with them other than replace brushes. Anyway the auto electric guy put the alternator on his test bed and tested it and declared that it was working fine. He advised testing the heavy wire had continuity to the battery which it does and after another 2 hours i had this watercooled piece of $hit back in the car and all connected up. Sure enough it was now charging, then it stopped, turned on the heated rear window and lights and again she started producing 14.6v. Mystery...........

Tried again this morning and nothing sitting at 12.4v after running for 5 mins or so.

So anyone any idea what is wrong??

The alternator is between 300 and 600 depending whether you go for a copy of the genuine Delphi item and i do not want to tell him to get a new one if not needed.

Anyone???

230K

 

[230K]

additional info

Hi

One other thing is that there are no warning lights on whenever the car is not charging.

The notification only start to appear when the voltage drops near 11v

Thanks,

230k

 

[Dieselman]

Does the alternator feed straight to the battery or via the front SAM or a battery control module?

Was the one way pulley working properly, they can be intermittent in operation.

It sounds like the regulator pack is iffy and not calling for delivery of power.

 

[Brian WH]

Are you sure it is the Alternator and not the Battery not taking the charge?

 

[230K]

Dieselman

I tested continuity of the big wire back to battery and it was fine but didnt trace the route to see if it goes into any module or whatever but this was with the battery disconnected i had continuity.

The one way pulley was working as far as i could see and the auto spark confirmed that when on load on his test bed.

Can't seem to be able to order regulator pack, only the brushes????

Brian

Battery seems fine, the ctek charger takes hours to take it to full capacity and after sitting overnight the car has 12.4 v so i am assuming all is fine there??

Why can't Mercedes have a charge light on these cars like they used to be?? Simple is best in my opinion. The difference trying to work on the 203 as compared to the 210 is HUGE. massive step in the wrong direction i feel. Why oh why do we need water cooled alternators????

Thanks,

Brian

 

[230K]

Update.....

My colleague bought a new alternator from Eurocarparts for £360. It was a Hella re-manufactured unit nice and shiny but the finish to the 2 water connections surfaces was really bad. The rounded taper had been machined off where the pipe goes in at the top so much so that it cut the new rubber I had to take it off again and round the edges to allow the pipe and rubber to glide in just like the original unit. The other water mating surface had been machined too but they missed a bit which was sitting proud. 2 minutes with emery paper had it acceptable.
So beware anyone buying the same unit to check the mating surfaces.


1 hour had the old one off but 2 and 1/2 hours to get it back on correctly.

Fired her up no leaks and she is charging

230k