Wiper linkage broken or 'popped off'

[johnny_quattro]

After a quick clear of the windscreen recently, my wipers stopped abruptly - pointing upwards, presumably paying homage to DTM cars. I opened the bonnet and saw that the lower link had popped off the top link. A quick search online revealed just one wiper linkage set and that was in Lithuania, and of course, it was left-hand drive. A call to Maria at A8Parts and it was established that there was no current stock. Yikes.

I called a friend who's pretty handy with mechanical things and we knocked up a Heath Robinson affair by drilling a 3mm hole through both the domed cap on the lower arm and into the metal lump on the top arm while the two items were linked in place. Inserted an M3 bolt from the bottom with washer, another in the middle and then one on the top which was then tightened enough to ensure it retained the top part without binding. A second nut was used to lock it, along with a dab of superglue as we had no Loctite. It all seems to work beautifully.

Ideally I'd like to replace the whole thing but that depends [a] on the availability of spare and [b] the condition of said spares. I'm going to monitor the situation over the coming days/weeks and I'll have a spare kit in the car in case it snaps or something. If it does, then I'll have to drill it again to take an M4 bolt - and you can get M4 nyloc nuts too.

[MikkiJayne]

A common problem, and a fairly common solution. The cause is usually the chromed steel ball losing its chrome and going rusty which then grinds away the inside of the plastic bushing. New bushings are available, but if the ball is worn out they won't help much.

The other cause is the wiper spindles seizing up in the bushings because the rain has washed all the grease out. The extra force needed to move them tends to escape at the weakest point, that being the plastic joint.

There is a design flaw in the plastic caps that go over the wiper spindles, in that the hole in the top is such that it allows rain water to pool on the top of the spindle, when then seeps in to the spindle and washes out the grease, then makes it all go rusty and seize up. I've been printing replacement caps which are a tighter fit to keep the water out, but they're only really useful once the mechanism has been apart and re-greased. Quite often the spindles are irreparably worn as well though, so there's not much that can be done at that point. If the spindles are still ok, the bushings they run in can be replaced, although this is a non-trivial task.

I've been meaning to re-engineer this with rose joints for some time now but haven't got round to it. Ideally I'd like to find a replacement for the spindles as well but thats proving tricky. The mechanism for the centre wiper is a tad complicated and not very easy to replicate though.

[Stromaluski]

Originally Posted by MikkiJayne

A common problem, and a fairly common solution. The cause is usually the chromed steel ball losing its chrome and going rusty which then grinds away the inside of the plastic bushing. New bushings are available, but if the ball is worn out they won't help much.

The other cause is the wiper spindles seizing up in the bushings because the rain has washed all the grease out. The extra force needed to move them tends to escape at the weakest point, that being the plastic joint.

There is a design flaw in the plastic caps that go over the wiper spindles, in that the hole in the top is such that it allows rain water to pool on the top of the spindle, when then seeps in to the spindle and washes out the grease, then makes it all go rusty and seize up. I've been printing replacement caps which are a tighter fit to keep the water out, but they're only really useful once the mechanism has been apart and re-greased. Quite often the spindles are irreparably worn as well though, so there's not much that can be done at that point. If the spindles are still ok, the bushings they run in can be replaced, although this is a non-trivial task.

I've been meaning to re-engineer this with rose joints for some time now but haven't got round to it. Ideally I'd like to find a replacement for the spindles as well but thats proving tricky. The mechanism for the centre wiper is a tad complicated and not very easy to replicate though.

One of my wiper spindles looked like this, with one of the bushing seized to it. I replaced the entire linkage with one from a parts car that was better, but still very much not great. I will eventually have to do something else.

[MikkiJayne]

Yeah thats what I mean about the spindles. You can see on that one where the chrome has worn through.

It might be possible to turn them down and fit a repair sleeve with new bushings. A grease fitting on the housing would help too.

This is the cover I made. The original is the same shape but has a larger hole in the centre so is really just cosmetic. This one will hopefully keep the spindle relatively well sealed from the rain.

[spannerrash]

I think I have a spare (used) unit kicking around somewhere if you want it. I can't vouch for its condition bearing in mind it's age but for the price of delivery, it's yours if you want it.

Without a doubt it will need stripping and Re-greasing.

PM me your address if you want it and give me some time as I'll have to dig it out and find something to package it in.

Cheers Frank

[MikkiJayne]

I'll collect any scrap / broken linkages too - they can usually contribute something to getting another unit working, or can be cores for when I figure out the rose joints

[Stromaluski]

Originally Posted by MikkiJayne

This is the cover I made. The original is the same shape but has a larger hole in the centre so is really just cosmetic. This one will hopefully keep the spindle relatively well sealed from the rain.

Do you sell those?

[MikkiJayne]

I wasn't planning to as they're just an experiment, but happy to send you a set if you cover the postage $10 to the usual address please

[Stromaluski]

Originally Posted by MikkiJayne

I wasn't planning to as they're just an experiment, but happy to send you a set if you cover the postage $10 to the usual address please

Thanks!

[johnny_quattro]

Originally Posted by MikkiJayne

Sticking 3 drainage holes there is a pretty silly design from Audi, in my opinion. The photo you attached shows the 3 holes which are directly above the wiper mechanism (driver's side) which has worn through and popped off on my vehicle. Remove the plastic vanity cover hiding the wiper motor and you'll see it in all it's glory. Drip drip drip straight on top of the rotating joint.

I'm convinced that this is the reason my wipers are borked in the first place. My previous fix lasted a month before it snapped the M3 bolt whilst in lane 2 of the A303 on the way back home from Somerset. A 2h 45m journey took me 6h 20m and I think I used pretty much every lay-by before diverting to Salisbury and purchasing some RainX. Managed to get home safely and was entertained for the remainder of my journey by the reverse-Matrix effect of the rain going up the windscreen.