Wiper Motor 75 116 280S

[stiffy]

We've been in a drought - so don't get to use the wipers that much - had a torrential downpour the other day and spent a gruelling few minutes driving slowly with a chamois and my right arm out the window wiping the windscreen whilst dodging hapless paedestrians.

They seemed to get stuck - and when I gave them a bit of a push they started briefly then seized. I wasn't sure whether I had them switched on or off after repeatedly trying different crazed methods to get them to move.

This morning I smelt burning plastic - so have removed the fuse. I think the motor is cooked.

I don't like where this is leading - I haven't seen any other postings about replacing the motor for a 116 - but all the others look fairly tedious.

I assume the motor is up under the dash - behind the heater. I don't want to go in there - please don't make me go there.

Any thoughts?

[wbain5280]

Here's a site for you:

http://www.w116.org/

http://handbook.w116.org/chassis_75_2.htm

electrical system, #82

http://handbook.w116.org/Chassis/82-680.pdf

[cth350]

On the cars prior to the w116, the wiper motor is easy to replace.
Can't think off-hand where it is on a 116; it's been too long.

Aside from removing the motor, you'll need to check the wiper transmission. Relacing that is quite a pain, since you need remove a great deal of the dash. You might get lucky, and be able to free it up in place.

Of course, I am presuming it's rusted up a bit. I don't think you'll know until you remove the motor.

-CTH

[stiffy]

thanks...

that section wasn't obvious when I checked the manual - thanks Warren.

It looks like some of it is accessible under the grille - but I hope i haven't ****ed up the transmission - that looks rather nasty (thanks CTH).

As per the norm with my posts - once i get started I'll take photos and post a running commentary of my woes.

If anyone else has any info I'd really appreciate it.

[Mad Mick]

May be simpler than you think, 'hopefully'.
Had the same thing happen to my '75 W116 and you can get to the wiper motor and motor drivebox easily by removing the chrome grill below the windscreen which is simply held by plastic grommets. You will see the wiper motor and drivebox combined and held by 3/4 small bolts. Remove these and lift out the motor and gearbox combination together. Inside the drive box is a simple linkage system and one of the rubber holding rings for one link had worn away. I needed to order the whole link from a Merc dealer at a cost of €20. in Ireland (maybe $15) Very simple job to do if this is the problem.
Fingers crossed for you.
Mad Mick.

[stiffy]

I literally have just come from working on it.

You're 100% spot on.

I am very happy to not have to try and take the motor away from the car, however - as finding the power plug under the dash is a real mofo.

Luckily I had the same problem as you - although I contacted a wrecker here in Sydney (Mortdale Spares) and they supplied a used piece of the linkage system quite cheap. I now just have to replace the linkage and press the new piece into place (looks straight forward, although I'm not sure if there is a tool to do this).

thanks for your responses

[Mad Mick]

It's great when what you think may be a big job, turns out to be small.
More often the opposite is true.
The new linkage piece should simply push on using finger strength.
Good Day.

[mendodiesel]

how does one remove the expanding rivets of the grill??

[stiffy]

If I recall, the rivets have plastic expanders that will snap off when you try to pull them out.

I was able to source new ones from a local Supercheap.

Just get the blade of a thin screwdriver and ease them out - alternatively, just drill them out and replace them, as the chances of getting them out without wrecking them is pretty slim.

[Mark DiSilvestro]

Originally Posted by mendodiesel

how does one remove the expanding rivets of the grill??

If they're like the ones on the W114/115 cowl vents, the plastic rivets have center pins that push out, releasing the rivet's grip on the holes. Then you can easily pry them out. Note that after a few decades, the plastic rivets are very brittle and may break anyway. If they are still good enough to reuse, you'll need to search under the cowl for those little pins you pushed out.

Happy Motoring, Mark

[Mike D]

[QUOTE=stiffy;1062134]window wiping the windscreen whilst dodging hapless paedestrians.

They seemed to get stuck - and when I gave them a bit of a push they started briefly then seized. I wasn't sure whether I had them switched on or off after repeatedly trying different crazed methods to get them to move.

Now THOSE two sentences gave me a bit of a laugh!

[stiffy]

I checked the local spares shop and they were fresh out of Hapless Paedestrian Remover.