windscreen wiper issue - help needed!

[95-540iLE]

Picked up the 3.6 M5 in Melbourne on Thursday. Drove it around there for a few days and it is now back here in Tassie with me.

Having a great time with it, love the sound and the feel of the power when the revs get over 4000, but still not sure I don't prefer the torque and more linear delviery of power from my M540i.

Anyway, on Friday night, as I drove towards the boat to take me from mainland Australia to Tasmania, a thunderstorm broke (and the temperature plunged about 10 degrees celsius to about 30 degrees). I turned the wipers on for the 1st time and no problems.

However, after about 5 mins, I noticed that the drivers arm wasn't going all the way down and in a few more strokes of the arm, stopped at the vertical position.

The passenger arm was working fine.

It appears that whatever grabs the arm and drives it no longer has the teeth or ability to grab any longer.

I stopped the car and you can now grab the arm and freely move it up and down.

Any idea what part it is that has worn out and how hard it is to fit.

Comments appreciated.

Cheers

[GJPinAU]

Have you compared the mechanism on the 540 to see what has gone amiss?

[genphreak]

However, after about 5 mins, I noticed that the drivers arm wasn't going all the way down and in a few more strokes of the arm, stopped at the vertical position. The passenger arm was working fine. It appears that whatever grabs the arm and drives it no longer has the teeth or ability to grab any longer. I stopped the car and you can now grab the arm and freely move it up and down. Any idea what part it is that has worn out and how hard it is to fit. Cheers

Sounds like the driver's arm spline is loose- not much else can cause this unless a linkage breaks (and wow) you would hear that. You need a 5mm allen key to tighten it, as well as a flat screwdriver to get it off/adjust it. Be sure to get it in the right position, if unsure make the arm overwipe the bottom of the screen rather than encourage it to go further over until you can inpsect the arm for the well known issue: 'Bonnet bashing arm'. This is common and can be caused by a twisted arm or sunken bonnet catches (caused by old bonnet struts becoming ineffective and allowing unwary persons (or the wind) to slam the bonnet (hopefully not on one's head) onto the catches (and promptly 'adjusting' them down to their lowest adjustment point on the frame).

The catches are easy to adjust (3x10mm nuts inside the gaurds near the ebox)- but that said my arm still hits, indeed almost every e34 I see seems to have this problem. ie Wiper arm hitting the bonnet risking damage to the wiper mechanism. BMW's service of them sucks (wiper component pricing is simply impossible).

Mine have just been in pieces again. They don't seem well documented by BMW or the Bently; there are two settings critical to the pressure device that are not well-covered.

I can adjust my arms to wipe correctly, ie the drivers side (the most critical from an adjustment point of view & mine has no problems with the passenger wiper) wipes from the far top corner of the screen to a horizontal position perfectly, but the arm itself hits the bonnet lip at the top of every wipe. This partly because I adjusted the arm so I got the right wipe points. I should have left it (I had originally thought it was retarded by one spline as it overwiped the bottom of the screen (no big deal) and missed going to the far corner by a fair way. After I adjusted the wipers to wipe correctly, the lower (curved) section of the arm badly hit the bonnet (as it had done before). I adjusted the bonnet locators to the highest vertical location, put 3 washers under the bonnet catches, but still the arm hits. Every wiper component is original BMW; but from inspection it is pretty obvious the arm has twisted near the pivot, from hitting the bonnet. Just now I replaced the motor due to a cracked internal cog form the strain of all the hits (Aussie stealer wanted US$400 for a new one). It is proving hard to get a new arm though- that's what I really need. For the time being I have twisted the arm back just a bit... am now considering buying a new arm from the stealer.

So don't just tighten the spline to get the wiper moving again, take care to examine why it was slipping in the first place (they don't). ie Be sure to look carefully for signs of the dreaded bonnet bash first- on the arms and the far edge of the bonnet.

Nick

[BobHarris]

Have you tried to tighten the nut that holds the arm onto the spline?

Edit: You seem to have it well coverded Nick. I started this before you but then got called away.

All the best

Bob

[genphreak]

Edit: You seem to have it well coverded Nick. I started this before you but then got called away. All the best Bob

That's great Bob, you kinda summed up what I was on about anyway! [and yet more proof that this is the board of choice for bimmer related info]

[95-540iLE]

Have taken a 5mm allen key and the arm is now engaging again. however, there are signs of the arm hitting the bonnet (hood) so, as recommended, I think I will need to investigate further.

thanks for the assistance.

Sounds like the driver's arm spline is loose- not much else can cause this unless a linkage breaks (and wow) you would hear that. You need a 5mm allen key to tighten it, as well as a flat screwdriver to get it off/adjust it. Be sure to get it in the right position, if unsure make the arm overwipe the bottom of the screen rather than encourage it to go further over until you cna inpsect the arm and the (well known issue): 'Bonnet bashing arm'. This is common and can be caused by a twisted arm or sunken bonnet catches (caused by old bonnet struts becoming ineffective and allowing unwary persons (or the wind) to slam the bonnet (hopefully not on one's head) onto the catches (and promptly 'adjusting' them down to their lowest adjustment point on the frame).

The catches are easy to adjust (3x10mm nuts inside the gaurds near the ebox)- but that said my arm still hits, indeed almost every e34 I see seems to have this problem. ie Wiper arm hitting the bonnet risking damage to the wiper mechanism. BMW's service of them sucks (wiper component pricing is simply impossible).

Mine have just been in pieces again. They don't seem well documented by BMW or the Bently; there are two settings critical to the pressure device that are not well-covered.

I can adjust my arms to wipe correctly, ie the drivers side (the most critical from an adjustment point of view & mine has no problems with the passenger wiper) wipes from the far top corner of the screen to a horizontal position perfectly, but the arm itself hits the bonnet lip at the top of every wipe. This partly because I adjusted the arm so I got the right wipe points. I should have left it (I had originally thought it was retarded by one spline as it overwiped the bottom of the screen (no big deal) and missed going to the far corner by a fair way. After I adjusted the wipers to wipe correctly, the lower (curved) section of the arm badly hit the bonnet (as it had done before). I adjusted the bonnet locators to the highest vertical location, put 3 washers under the bonnet catches, but still the arm hits. Every wiper component is original BMW; but from inspection it is pretty obvious the arm has twisted near the pivot, from hitting the bonnet. Just now I replaced the motor due to a cracked internal cog form the strain of all the hits (Aussie stealer wanted US$400 for a new one). It is proving hard to get a new arm though- that's what I really need. For the time being I have twisted the arm back just a bit... am now considering buying a new arm from the stealer.

So don't just tighten the spline to get the wiper moving again, take care to examine why it was slipping in the first place (they don't). ie Be sure to look carefully for signs of bonnet bash first- on the arms and the far edge of the bonnet.

Nick

[ILoveMPower]

I'm glad to see this, the same thing happened to me the other day for my passenger side wiper. I assumed it was from the freezing weather and the snow on my windshield. I'll be sure to check it out today...

[632 Regal]

wiper arms commonly hit the hood, something about a worn bushing or you can replace the arm to a new style one that doesnt match the other one...

[Paul in NZ]

they all hit the hood dont they....but i am sure its the passengers one that hits the bonnet on mine.....my drivers side overwipes slightly at the bottom of the wipe making a racket on fast.Glad you have got it sorted though David.
How did the melbourne meet go?

[95-540iLE]

Thanks Paul

Melbourne meet went well. Had 2 LE's (#16 & #52), my M5, an M6, an Alpina B10, some other assorted E34's, a couple of E28's and some E30's for good measure.

A pic of some of the cars attending is attached.

Cheers

they all hit the hood dont they....but i am sure its the passengers one that hits the bonnet on mine.....my drivers side overwipes slightly at the bottom of the wipe making a racket on fast.Glad you have got it sorted though David.
How did the melbourne meet go?