Wiper transmission gear -- 94 c280
 

Lots of pollen on the windshield this morning. Hit the "spray" trigger and the wiper started moving. It went all the way over to the passenger side for the 2nd time but stopped halfway back over. Just stopped. No indication prior, no slowing down, no nothing. :eek:

I turned the wipers off.

Jumped out and the wiper can be moved back and forth with very mild resistance.:confused:

Turn wiper on -- you hear the motor running fine.

I am assuming that one of the two gears has stripped. Although -- it seems weird that it would work perfectly and then just stop immediately. It would take a little travel distance for the gears to strip and stop, I would think.

Anyway -- look at picture 3 in this other thread: http://www.peachparts.com/shopforum/showthread.php?t=66429 I am assuming that he big gear (on the left) is metal and that the smaller one is plastic (although the one in this picture appears to be brass).

How safe is it to assume that the small gear is the problem? I'd like to get that part ordered from odometergears.com/mercedes today for $50 and do it this weekend.

Does everyone agree that the gears are the problem and that it is almost certainly the smaller one?

Thank you for the help.

Update:

Upon the recommendation of my mechanic, I rotated the wiper. The telescoping action is firm and strong = NOT the gear. Motor is running = not the motor.

He suggests that a nut came off of the arm. He is not available right now, but would you think he is referring to the nut on the bottom of the transmission hub or in the assembly toward the passenger side of the car?

Either the nut that holds the linkage to the motor OR the nut that holds the linkage to the gearing could be loose.

i have been there several times.you will find that the nut securing the linkage to the motor/gearbox has come off completely.with a magnet you will find it down in the cavity.be careful putting it back together that you line it up in the park position or you will be pulling it apart twice.

Well, you and m.b.doc were exactly right. This is exactly what it was. Now...I certainly wish I had rechecked this board before I put it back together...I did exactly what you said and my wiper parks at 75 degrees to the passenger side. :rolleyes:

Question: Is there a way other than trial and error to get it tightened in the correct position? (At least with this design and I can manually rotate it out of the way until I have another hour to change it.) I did lube it all up while in there, though.

Loosen both nuts & disconnect the linkage from both ends. loose but not OFF.

Then allow motor to run & park. set the wiper arm to the park position & then re-tighten the nuts.

Both? Not sure I follow. The only loose nut was on the very bottom of the motor.

Thanks.

ok once the motor has been turned on and off [should now be in park]set up the linkage so that the long and short rods are directly over each other.this makes it diff to tighten the nut but that is the correct position.when you look at it it will make sense.

Thanks for following up on this. Let me make sure I am clear on this. The ONLY thing that came loose was the nut on the bottom of the motor -- on the motor shaft. I tightened that...but didn't have the wiper at the right position.

Is this the only nut I need to loosen, then reposition, then retighten -- or are you telling me there is another? Also, by lining up the long/short rods -- am I accomplishing anything different than just loosening that nut and rotating the blade to the proper park position?

Thanks