I just came to the conclusion that my windshield wipers are not behaving properly on the W140. I've always thought that the unwiped area at the drivers top corner was obnoxious or an oversight of Benz, but now I'm lead to believe that the drivers wiper blade is suppose to translate along its length like the E320. A recent post defined replacement of a (presumed) nylon gear within the wiper motor assembly (and that it wasn't available as a replacement part.)

Okay...I'm the type of guy that scrooge's his way through everything and am looking for pointers on the dissassembly of the wiper assembly before I attempt the repair. Don't really want to have it appart for long.

Any help or pointers would be appreciated.

Ron

__________________
1995 E320 -171k-km
1995 S420 -333k-km

BTDT. The failure in my case was the splines on the nylon gear that's a [poor excuse for a] splined fit on the driver side extension pivot arm stripped so the gear wouldn't drive the extension pivot arm as the gear ran along the track on the inside of the case. It'll make sense when you see it.

JB Weld didn't hold the gear on the extension pivot arm. The W124 and W201 use a metal gear that doesn't fit. The W208 and W210 use a nylon gear that doesn't fit. Thanks to a forum member, I was directed to an eBay listing for a W140 being parted out and got the wiper assembly for ~$50 with no motor. The wrecking yards I asked wanted $250-400 for a used wiper assembly with no motor.

To remove the wiper assembly, remove the plastic box/chamber that sits ahead of the wiper assembly. I think it's held by 5 Philips head screws. You'll have to detach a couple of vacuum hoses near the right hood hinge and some hoses and wires on the other end. Nothing's gonna leak or anything.

Remove the ~10 clips holding the lower windshield trim in place. It's those funny clips that are something like a drywall anchor. Mine were stuck so I sheared off the heads with a blade and bought new ones. By stopping the wipers at near vertical, you should be able to wiggle the center trim piece off the car. The center trim piece might be held by a nut at its lowest point (don't quite remember). Set the wipers back to rest position.

Remove the right arm like you would any old wiper arm. Remove the set screw holding the driver wiper arm to the extending arm. Put some cardboard and towels under the joint. Wiggle the driver wiper arm off the extending shaft. The cardboard and towels are there so the spring force doesn't send the driver wiper arm into the windshield.

Disconnect the wiper motor harness from behind the brake booster. Snake the harness into the wiper assembly cavity.

IIRC there are 3 attachment points for the wiper assembly - by the right wiper pivot, below the base of the driver wiper pivot, and near the motor. With those nuts/bolts released, it's a matter of wiggling the assembly out of the car. What works for me is to roll the assebly about the car's pitch axis rolling the lower forward edge of the assembly upwards and to the back. This gets the right side pivot arm out of its slot, and that's really the only thing holding it in place at this point.

To get into the driver side gear case, mark the relationship of drive arm and the driven shaft, remove the 19(?)mm nut holding the drive arm to the driven shaft, then remove the circlip on the driven shaft. The case should come apart.

If you find the problem to be something other than the fit of the nylon gear on the driven shaft, I probably have spares you can use.

Let me know if one of your front seats won't raise :/

Sixto
95 S420
87 300SDL

I just got finished r&r the windshield wiper assembly & glad I did. Sixto...you were dead on the money, the nylon gear had broken in half and was resting on the end of the container area...pieces of it everywhere but still 2 large chunks that actually where jamming the windshield wiper from its full sweep. Glad I removed the pieces in this instance as it would have destroyed the wiper assembly over time. Full sweep now.

Regarding the nylon gear. I'm going to take the pieces to a gear place locally. As they explain it, setup is the major cost, turning out each additional unit is next to nothing, so.....

Looking for orders if anybody wants to gamble on this procedure. Pretty sure I can get a match to install.

Ron

__________________
1995 E320 -171k-km
1995 S420 -333k-km

Ron,

If the gear fits a 1992 300SE, give me a quote on one.

Tim

One word of caution for anyone doing this repair. You must be VERY careful when removing and refitting the wiper assembly to the car. You do not want to chip the bottom edge of the windshield because it will cause it to crack from the chipped spot.Trust me I learned this the hard way. Good luck, Robert.

__________________
Mercedes Benz Master Tech - Retired

Ron,

I can do you one better. I my nylon gear is intact except for stripped internal splines. It might be cracked but as yet it has not come apart. I can lend it to you for measurement. If I were doing this, I'd get some aluminum gears made and modify the shaft to take a set screw. Or fabricate the gear with a D inner bore and shave down the shaft to take it.

Sixto
95 S420
87 300SDL

I didn't hear anything beyond this thread. AFAIK the seat gear halves are still in my garage. No idea where the wiper gear is. Maybe I sent it to Ron.

My 95 S420 is long gone and my 93 SD, also gone, had all the gears intact.

Entire 140s are selling for under $5000 all around me so wrecking yards should have good stocks of these parts. The trick is getting them to sell just the part rather than an entire wiper or seat assembly. Be patient and check eBay weekly.

I know the fellow on this forum who goes by dieseldiehard. His name isn't Jamie Reed, though.

Sixto
87 300D

I've got a reliable machine shop near me that can cut the gears just fine. I think I am going to do a 25-50 gear production run and put the extras up on my website, www.fryerpower.com.

I would love to get my hands on a W140 with black interior for 500 bucks!

Thanks for the response!

Jamie doesn't go by the name dieseldiehard. He's a guy I knew from the Navy 10 years ago who loved diesel MBs. I think he had an onld 240 back then. I figure if I keep it in my sig. eventually he will see it.

-Jim

__________________
1995 S350D, Green with black leather interior.
Bought January 2008 w/ 233,xxx miles.
I did 22,000 miles during the first year of ownership.