Ok, I have the standard wiper motor issue. On an 87 300D.

I have taken the assembly out, and removed the motor, greased up the gears etc. The transmission seems fine now. I took the electric motor out by itself and plugged it back in and is slllloooowww... I can see the issue is with the motor itself or the voltage to it etc.

1. is there a how to on testing the voltage to the motor (to make sure it's not just the crappy switch inside causing my issues)

2. Is there a way to rebuild the motor?

3. If no rebuild, what the best place to buy or get a good replacement?

The electric motor does seem to work in all settings, parks correctly etc, it just seems slow in all those settings. I can take a small video of it's operation if need be.

Well, crap.

Ok, forget testing it... I tried and fried it.

I found this on the forum... Followed it and sparks flew when I did poss to #4... Now the motor will not park. So don't use this information for a 87 300D.


Testing wiper motor

Warmblood58, before embarking in checking or replacing relay or switch, it is suggested you run the following test to ascertain whether your wiper motor is faulty.

Testing wiper motor

Disconnect the plug on top of the wiper motor and put it to one side.
On the motor there is the male plug connector with 5 pins (2 on the left and 3 on the right as per pics). Ignore sequence of pin No.1. Number them as follows:

From the left (there is only 2 pins) top left number 3 and bottom left number 5.
From the right (there is 3 pins) top number 2, middle number 4 and bottom number 6.
Using crocodile clips make following connections:

Connect a positive and negative line to the battery (or 12V source).
Clamp positive line to plug connector pin No.3 and negative line to pin No.6.
Connect an additional line to positive pole of battery and hold other end of this line against plug pin No.2, then 4 and then 5, one after another.

Pin no.2 actuates slow wiper motion
Pin no.4 actuates fast wiper motion
Pin no.5 actuates interval motion

If all above motions occur, your motor is fine and you need to find relay and switches for the fault as others have advised on earlier posts.

There's a used one on the parts forum.

__________________

Gone to the dark side

- Jeff

Where?

Here they have it listed for 97 bucks

http://www.importecwarehouse.com/Mercedes-Wiper-Motor-W124-124-Bosch-System-87-95-p/mb1248200708.htm

Oreilly auto has a reman for 115 lifetime warranty

http://www.oreillyauto.com/site/c/detail/A1C0/431513.oap?year=1987&make=Mercedes-Benz&model=300D&vi=1430267&keyword=wiper+motor&pt=03292&ppt=C0047

Auto parts warehouse Bosch OE, 107.00 free shipping.

http://www.***********************/details/QQMercedes_BenzQQ300DQQBoschQQWiper_MotorQQ19871993QQW0133-1603823.html

$45 gets you a used motor delivered to your door. Its from a 1992 400E I'm parting out. Believe it to be the same as yours but you would need to verify. If interested, I'll remove and test operation. I also have the transmission arm available.

__________________
Hanno
'79 6.9 Sold (after 27 years)
'83 280SL, 5 spd.
'94 E320 Sdn. 5 spd conversion
'02 E320 Sdn.(on loan to mom!)
'87 300E (5 spd. conversion) Sold
'05 E500 Wagon