Window won't go down - PeachParts Mercedes-Benz Forum

Richard Eldridge · #1 09-23-2003, 11:00 AM

The front passenger side window on my 300TD recently decided to not go down. When I press the switch the lights dim a bit, and I tried connecting the wires to another switch without effect.

The window worked perfectly before, it went up and down smoothly and with no noises, just like new.

Is there a solution to this other than replacing the motor? Is there something other than the motor that could be bad?

Perhaps lubricating the motor? But how? I have white lithium grease and would gladly buy whatever exotic grease that is needed.

I hear the thing is riveted on. Can I use a pop riveter to reinslall a new motor?

What is the easiest way to fix this? Should I trust a "new" junkyard window motor?

#2 09-24-2003, 07:09 PM

The practical solution is a new riser. They are not very servicable. You can either pop rivet the new one in place or simply use nuts and bolts.

Plan on having hands and arms that look like they went through a meat grinder after the job is done.

Best of luck,

dmorrison · #3 09-24-2003, 07:20 PM

If the light dimmed then electricity is getting to the window motor. The window does not have a cutout switch. It just gets to the limit stop and the motor stalls.
The plastic slide that is located in the bottom runner may have jambed as it broke. It can be purchased at the dealer and replaced.
Remove the scissor assembly
Open the door by removing the panel and see if the plastic slide is comming apart. This will now need replacing if it is.
You drill the unit out and install the new unit. Some cautions.
You will do best if you have an assistant. Utherwise you need 4 hands. When peening over the new metal shaft. You can use a ball peen hammer, and a punch. Make sure you do not hit the plastic or have the base resting on the plastic. You will destroy the new slide.
Make or have a small metal shape just the size of the metal that is exposed thru the plastic. You can figure this out as you look at it. Peen the new unit in. Lube the slide with lithium grease and install the scissor unit back in the door.
Gloves and long sleeves will prevent a lot of scratches due to the door metal edges, as Larry explained you can really cut up your hands unless you are carefull. Or tape the edges of the door openings.

Dave

Richard Eldridge · #4 09-25-2003, 01:16 PM

Thanks for the advice. I think I'll buy the plastic thingie, since I will need it either way, and then see if the motor is dead. It worked perfectly until it stopped one day.

I am planning to follow Thomaspin's advice on his website and use the duct tape, sleves and gloves to protect my hands and arms. I was badly mauled by a Buick once before when replacing that silly rear vent on an 82 Regal. It is hard to believe, but the rear windows on all GM cars for many of the "Roger Smith Years" did not roll down., except for the Cadillacs.

I hope poprivit gun can fit in there. I am not sure of how to peen, as I have never peened before.

Once more, many thanks for your help.

Theurig · #5 10-29-2003, 10:28 PM

Well I don't know if you have already fixed your problem as seeing it was posted in Sept, but I just had the same exact problem with my 83 380 sel, the window would not move but was working perfectly before. check the switch it is quite easy. When you remove it , also remove the affected button slowly, a lot of gunk had accumulated and thus when I pressed the switch the contacts where blocked by the gunk, so the window didn't move. clean up with some CRC and window was perfect, I would say 96 % that that is your problem.

dmorrison · #6 10-30-2003, 12:27 AM

Theurig

Actually in his situation the switch is working because he stated the lights are diming when he presses the switch. so it is probably the slide or the sissor assembly.

Peening

A round shaft will stick up thru the metal unit that you are trying to attach the shft to. To peen it over you use a ball peen hammer

http://www.amazon.com/exec/obidos/tg/stores/browse/-/553192/104-2352008-7207964

Use the rounded end to shape the shaft into a rounded over section that tightly holds the shaft to the metal plate.

The shaft as it comes thru the metal will now have a rivet shape.

Dave

The picture shows the rivet shaft going thru the metal and the rivet then peened over to attach it.

Richard Eldridge · #7 10-30-2003, 05:46 PM

I am pretty sure that the switch is okay, as I took it out and swapped it with a working switch, and the passenger side window still would not come down.

I haven't gotten around to this yet. I did buy a set of window hardware.

The local guys (Finish Line here in Miami) tell me that a new window motor will cost me $85 plus tax. But I am guessing that it is simply something stuck or broken, since the window went up and down rapidly and smoothly with nary a groan or squeak.

I have never peened anything. I am a novice peener.

Must I peen this on the car, that is, sideways, or can I do my peening on a nice, flat surface?

Where can I find rivets for some practice peening?

TCG · #8 10-30-2003, 07:15 PM

Give this a quick try. Turn the key on, hold the switch in the down position and SLAM the door (a couple of times). I've freed up a few that way.

TG

Richard Eldridge · #9 10-30-2003, 07:45 PM

Thanks! I'll give it a try.
I hope it does not get stuck in the down position.

Q · #10 10-30-2003, 09:16 PM

Peening is very simple. First, you will have to get one of those coarse grinder deals for your drill if you don't have a Dremel tool. Once you grind the old pin down a bit, you can knock it through the hole. Insert new pin and brace the back against something solid. Take any type hammer and whack away at it. The end of the pin will deform and not allow the pin to exit the hole. It doesn't have to be pretty to make it work. I've done this on one of my windows. I have another one waiting in the wings to be fixed. Honestly, the worst part is getting the door panel off and back on.

abe g · #11 10-31-2003, 11:41 AM

About every 3-4 years on ly 77 450 sl, awindow will"freeze up". Before you take anything apart, try spaying with extnesin nozzle, wd-40 into door around morot and scissors mechanisism. Check glass for alignment. hold door open, pull up or push down same time as trying switch. I did this 2days ago window works fine! No ned to dassemble anything Try this first! Abe G

Thomaspin · #12 10-31-2003, 12:31 PM

While my use of tape on the motor opening may strike some as pretentious, the absence of scars on my hands suggests that 2 minutes putting the tape on is time well spent - I have done this job several times and have yet to hurt myself.

Now replacing vacuum pods on a W126....well, that's a different matter....