Hi guys, I'm on my 3rd connector in a month ('97 E420). The original didn't leak, but I changed it out while I was doing the transmission service (as preventive maintenance).

The replacement connector worked initially, but leaked badly (lost at least 1 liter) after the car sat for about 5 days.

I replaced it again, and had the exact same experience, making me think it's something other than the connector. I made very sure all o-rings were in place, the 7mm screw was tightened properly, everything was clean, etc.

I'm hoping someone has an idea about what might be wrong. I really don't want to use rtv to seal it up, but I'm running out of ideas.

Thanks! I appreciate any ideas you all might have.

Ther are 2 o-rings on the plug you remove (7mm) bolt. If the o-rings are OK then the plug might be cracked. The harness plug won't cause a leak.

Might have the wrong 0-rings. The replacements are white.

__________________
1993 400E


Mercedes Benz technician since 1982

ASE Master technician to 12/2015

Thanks clarkz71

Interesting ... of the 3 connectors I've had, all have had black 0-rings, not white (the original connector, one replacement from ********, and one replacement from the dealer).

Regarding your comment that the harness plug won't cause a leak - does this mean that the design of the connector is supposed to prevent the fluid from entering the connector? It seems like this should be true, but I've been having a hard time trying to figure out what prevents the fluid from entering the connector through the holes in the bottom of the connector (the holes that the electrical pins go through, and the other holes in that area).

Thanks again clarkz7, and to anyone else who can add anything about this!