Hi wonder if someone can help, my E230 (1991) 4 Cyl Benz recently started to drain the battery totally out. I started the car and removed the ground lead to the battery and the car engine shutts off, so I assume the alternator is not working (maybe the brushes or the voltage regulator) well replaced them and still the same. I do see a voltage increase accross the battery when I start the engine so I assume the alternator is working fine. would you know what could be the issue, this way the battery will run for 2 days and fully drain (car is running of the battery), is there a cuttoff or switch over relay that might not be working? but where are these located. would highly apprciate anyone's help/thought on this one. many thanks

 

no cut off relay.

the alternator is still bad (maybe diodes) since the car shuts off whenever you remove the battery.

 

many thanks Sleepwalker, are the diodes easely removable / fixable? same as the brushes and voltage regulator? I actually don't know what they look like and their location. thanks

 

diodes are attached to the rectifier base. you need to heat the lead to pull it out.

it got two types. negative body and positive body.

you need to test the alternator first. the wave pattern is different if the diodes are bad.

 

Alrighty, so now I've gone ahead and bought a new alternator and am having difficulties installing it. need to lossen the fan belt and to do that need to get to the tentioner bolt and to do that need to remove the fan shroud and to do that need to remove the fan (it won't come off without it, not enough room).

can you please help me on the below questions:
1. the bolt that holds the fan in place, to losen it do I need to turn it counter clock or clock?
2. fan belt how do I lossen the tentioner pully, I see a bolt next to the steering pump, is this it, if so then again to loosen is it CC or clock?

greatly appreciate your help........

 

ok, so I did manage to install the new alternator but in the process loosened the belt and now I hear a squeling noise from the tensioner pully i think. does anyone know how to loosen/remove the engine fan so I can habve more space to work on? thanks