Well, I headed for Kansas City this morning in my 300E. My windshield wiper started hesitating at the corners, that is when it extends to the corners. It then got to where it was slower on high speed than low speed. By the time I rolled into town it would barely run and at one point I smelled a burning electrical smell which might not have even come from my car, but the wiper kept working, struggling, but working.

When I pulled into the hotel the car was running fine, but when I started it up it would not rev up. After about fifteen seconds, it finally picked up RPM and ran normally. I went to eat and it did this same thing again. Is that usually the OVP or the fuel pump relay, or is it the fuel pump going out?

In your experiences, guys, will replacing the windshield wiper motor correct that problem or is it the mechanism that is binding up, or is the eccentric mechanism part of the windshield wiper motor?

Thanks for your help. I should be able to get around while I'm in KC with someone else, and hopefully the rain will clear by Thursday afternoon when I head home.

Wish me luck and please offer your experience about these two items.

Have a great day,

Larry:

I'm sure you've thought of this - I'll thow it out anyway.

It's been my experience that wipers slowing down are often tirmes a sign of a tired battery. If the battery is tired, would this not affect the OVP and other mission-critical electrics?

My 2 cents.

There's always Rain-X in an emergency - it does work unless it's really coming down. Of course it's got to be dry to put it on.

ps - I thought KC was about to get a big ice storm.

No, it's not about to get a big ice storm, it is GETTING a big ice storm.

Yes, I've thought about the battery and alternator, except I drove all the way here, over 400 miles with the headlights on, so the alternator and battery seem to be staying up with everything.

There certainly could, however be something electrical and in common with both problems.

Thanks, and please keep your thoughts and suggestions coming.

Have a great day,

Larry,
I'm far from an expert on this, but have been doing some research on monowipers and have thought about overhauling mine just prophylactically. What I do know is that the eccentric mechanism is part of the wiper transmission, NOT part of the motor. I have read of a number of W124s where their wipers slowed down progressively until they stopped, and were able to be put back into service by overhauling the transmission and using a good quality lube. Hopefully that could explain the wiper problem and be a cheap fix (which is good since the monowiper tranmission is an expensive item -- I've heard about $700-900!)

On the other hand, what could explain both problems you're having? Maybe a bad ground under the hood???

P.S. I know you do your own repair work, but if you don't mind driving another 180 miles north, I know a GREAT tech here in Omaha (but watch out, we're getting hammered with snow).

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Steve
'93 400E

My mono wiper was noisy and catching at the sides too, fortunately I could overhaul it without being 400 miles from home. It is an easy job. Remove all the plastic covers that are over the transmission, under the big one that is in the center you will see the mechanism, it is 4 rollers that sit between two rails. Those rails become bent, they wear out, and it doesn't allow the rollers to move freely back and forth. You can align the rails, lube it up and you should be good to go for a few more years! Good luck!
Brian

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Brian W. Heitman

www.MBCA.org/northtexas

Join MBCA!!!

Good luck and hope you make it home ok

Thanks for all the responses. I have decided that I believe it is the wiper transmission as mentioned here. Especially since it got progressively worse as I got into cooler air, thickening the grease. It was something like 58 degrees when I left and 30 degrees when I got here.

As far as the engine problem, I've had it happen before and it went away. It was only 30 degrees when I was having the problem and the car only sat about 20 minutes before restarting one time and five minutes the other. I don't think that at 30 degrees, it would have had time to freeze. I may get some B12 and put in the fuel just to be safe though. It wouldn't hurt to get out any moisture that might be in there.

Thanks again,

during a Christmas trip from Boston to Cincinnati - as the temperature got progressively colder the wipers slowed down. As the weather warmed during the week the wiper function returned to normal. I also think the windshield got quite a bit of salt spray on it, which increased the drag on the wiper motor, exacerbating the problem. It is probably time to relube that mechanism (which I have never done). Maybe you could, as a temporary measure, spray some WD40 on the wiper transmission?

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Chip Johnson

http://www.club202.com/forums/showthread.php?s=&threadid=3109&highlight=wiper

I've done this on my c280 a couple of times over the years. It's dirt simple. Use lithium grease only. The old grease will collect in a hardened blob at the end of travel on the slides. Clean it off. I have found the lithium grease good for a very wide temperature range. WD40 has poor lubricating properties, and if you are going to go to the trouble of removing the transmission cover, you are as far ahead to use the right product.

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'96 C280 (gone)
'97 C36
'05 C230k