Wiper linkage

[ChrisHC]

I have done something very stupid while replacing the wiper motor, I managed to break the plastic joint between the crank arm on the wiper motor and the drive rod connecting to the wheel box. I cannot explain why I was trying to take this apart, I have removed the motor before and should have remembered that there was no need to separate the arm and the rod.

It appears to me that I shall have to replace the drive rod as it would not be possible to insert a new plastic joint into it. To do that, do I need to take out the entire linkage system, or is there another way of getting to the wheelbox end of the rod? Should the plastic fitting click off and on the ball of the ball joint?

[ChrisHC]

I will answer my own question in case anyone needs to know for the future. To get to the centre part of the linkage, below the passenger side wiper, you have to remove the bulkhead cover plate and take out the cabin air blower. There are several videos about this on YouTube, from which it seems there are different types of cover over the blower motor. With that out of the way, you can reach the linkage. It may be helpful to remove the wiper arm and undo the wiper spindle so that the gear can be lowered to make the wheelbox more accessible. The plastic cups in the linkage can be easily levered off the balls on the arms, and snapped back on in due course. It was a good opportunity to lightly lubricate the blower motor bearings and to remove dead leaves from the heater radiator, visible below the motor housing.

The blower motor went back in easily enough, but getting the four pieces of the cover back on proved more difficult. The combination of old age and yesterday's cold weather made the plastic very brittle, and the tags broke off on the driver's side, meaning I had to jury-rig an arrangement of cable ties over the top to make sure the cover was held down, any sideways movement can cause the blower fan to foul the cover. The other side covers I took inside the house and warmed them up on top of a radiator for a while. This worked very well and that side snapped into place as easily as on the YouTube videos shot in much warmer weather. Then it was a matter of Haynes Manual reassemble it reverse order stuff, making sure the cables on the bulkhead cover plate were kept clear of the manifold which is very close. The wipers needed some small adjustment but now all is well and working fine.

[Contours]

A fairly messy task in bad conditions. I recall an argument on some forum where a couple of supposedly knowledgeable mechanics reckoned it was almost impossible to replace an e30 wiper linkage as the car seemed built around it. It is very surprising how long this wiper linkage lasts--mine is 30 years old , there's no play and is in every day use considering we've only had about 10 good days in that time.

[Brianmoooore]

I recall an argument on some forum where a couple of supposedly knowledgeable mechanics reckoned it was almost impossible to replace an e30 wiper linkage as the car seemed built around it.

This will be 'knowledgeable mechanics' who have not discovered the removable bulkhead panel. An E30 RH drive wiper mechanism can be easily removed without forcing anything at all.
To be fair, I'd owned an E30 for a couple of years before I discovered the panel. BMW designers did a fairly good job of camouflaging it.
As I think the OP now knows, there's never any reason to separate any of the linkage parts to release the mechanism from the motor. Removing the nut on the end of the motor shaft is all that's required.
The linkage parts do just push on and off of their respective ball joints, but as touched on up the thread, plastics don't like the cold, so warm things up in cold weather.