W123 water leak / sway bar bushings - PeachParts Mercedes-Benz Forum

Johnhef · #1 10-25-2005, 09:32 PM

I am still trying to track down my water leak problem.

Planned on playing with it a little tonight but the sway bushings took too long. Basically after a run through the carwash or when its rained overnight, with the first 90 degree left turn i make, it dumps a lot of water onto the blower motor from inside the heater box. My blower motor is apparently not a big fan of this. I had to replace it the other night after it locked up and started cooking.

I have covered most of the usual problem areas, under the battery tray has been sealed 2 years ago, still holding -no leaks there. The hood spring cavities have been clean and drain as they're supposed to. The left and right side vent/cowl drains work as they're supposed to and the heater box drain doesn't appear to be clogged so I'm at a loss. Where the hell is the water coming from and why doesn't it drain out of the box on its own?

I don't believe its my sunroof drains ( I think I've checked these before) but I'll test them tomorrow night.

What I did end up doing tonight was replacing my sway bar bushings. The old ones were trashed, almost an inch of play with the bar. The right side was easy to replace- remove the battery tray and easy access to it. The left side was a bit harder. I suppose it could be made much easier by removing the brake booster, but I didn't have enough time to do all that tonight. I was able to access the top nut from inside the wheelwell and the lower nut from above the brake booster. I greased up the bar and slid the new bushing in from near the oil filter housing, it was a tight squeeze getting it behind the booster but I managed to make it work. Steering did feel a little tighter on the drive home, but I thought I'd mention it incase anybody was thinking of doing the same.

samiam4 · #2 10-26-2005, 09:51 PM

Let's see...

Sounds like the water is getting into the air box which eliminates my normal- windshield gasket response(which seems to be the problem 95% of the time).

Take the wiper arms off the car, push the two piece clips apart and remove the vent covers. Then remove the cowling cover by it's plastic rivets. You'll probably have to splurge for a few new ones as old plastic does break. Now, there should be no water standing under there or it will go down the airbox.
Wait- there are rubber 1-way drains on the firewall that drain this area- these could be stuck closed!! Much easier place to start.

I sat in my car with a maglight in the rain. Look at the perimeter of the windshield gasket. Have the lower dash pannels removed and look underneath- you should be able to find where it is dripping.

Keep after it - you'll find it!
Michael

Johnhef · #3 10-27-2005, 09:40 PM

I finished up testing everything else the other night, sunroof drains are all ok. The heater box drain as it turns out was clogged further up in the tube, but after I cleaned it out, I soaked down the car, waited 10 minutes or so)and then made a hard left turn and immediatly stopped and sure enough, I could hear water spashing onto the blower motor again, so apparently I still have a problem.

I havent tried taking that center piece off yet, thats a great place for me to start next time, thanks. Also give me a good excuse to lube up my squeaking wiper linkage.

Johnhef · #4 10-28-2005, 07:47 PM

Ok I think I may have fixed it this time.

I definitly need to replace the front windshield seal as its hard as a rock, although no leaks on the floor inside yet. I pulled both vent covers and removed the center metal cowl piece. right in the center at the base of the windshield was some rust bubbles, so that might have possibly been my source of the leak. I can see now that the water could have been sitting in that part under the wiper motor and when on a left turn, would dump it directly on top of the blower motor, as that flat area will allow water to collect and not drain out anywhere. It did seem like a small area to have that much water collect but I am optimistic about it. I used some mb clear sealant under the rock hard window gasket and pushed the cowl piece back in place. I'll spray the car down again after its dry and see if I still get any water inside my heater box.

Also greased up the wiper linkage, that stuff looked horrible. so nice and quiet now!