Quick bit of help re misbehaving wipers

[Richard_420R]

Hi all - hope everyone had/is having a good festive season!

I had my wiper motor replaced under warranty but it's always (and still is) a right pain.  It just sticks and needs a firm prod to get it moving again.  This is hard when strapped in and on a motorway etc.

I've just had a fiddle and looks like the posts are grinding a bit so just popped in some wd40 and ran them for a bit.  They seem a lot better now but am wondering if there is a standard maintenance procedure for this.  Ie a particular type of grease or a way of cleaning/oiling to ensure this doesn't happen.  Any ideas or suggestions?  Am thinking the wd40 might be too thin etc and it needs something different.

Rich. 

[Jonathan Kay]

I can't remember it being discussed... I'll have a look.

If you've had two with the same problem I'd check the electrics, and is it possible that there's something about the fitting that's causing both to bind?

(I can't remember how easy they are to fit... did you do the replacement yourself?)

Happy Christmas

Jonathan

[Richard_420R]

Hi Jonathan, it was done by Oakmere as I had it done under warranty.  
How smooth should the mechanism sound?  On mine it sound a bit 'grindy' - once it's running to and fro it goes quite smoothly and it's normally on first/cold operation where it can move about 1cm and then stop - if I give it a bit of a push it will run okay but that's not really an option when on the move.  I wonder if the mechanism wasn't correctly lubricated during factory build or something - suspect first motor was burnt out due to inability to move the mechanism.

For once this doesn't quite seem like a "they all do that sir" which was what I was expecting ;)

Rich. 

[Jonathan Kay]

I don't think that they all do! And I didn't find anything in the archives.

Jonathan

[OldAndrewE]

Is the mechanism still essentially the classic Mini system.  Should not be that noisy and certainly not "grindy".  Sounds to me as if something is not lubricated/installed correctly and possibly that one of the rack tubes has been bent and the rack is binding

[Richard_420R]

Thanks.  Is there a noddy guide somewhere to get into the scuttle to access and take a look?  My maintenance abilities are pretty weak - changing brake pads is about all I'm doing for the moment.  Oakmere is too long a drive for me aside from my annual service - and for some reason I didn't ask them to look at this issue when I took it recently - must have been working fine for a bit!

Rich. 

[Richard_420R]

... and a bent tube is a possibility as I manhandled the blades in a forlorn attempt to get them going when stuck in rain on a motorway.  This was on the trip that got the motor replaced but maybe there was damage to the mechanism that they didn't spot.  Eyeballing it would be handy but can't see an easy way to do that and my googling so far hasn't unturned an easy video/how-to guide.  Any pointers would be gratefully received - including a "don't try this at home if you're not very good at it" advice and I can find someone to take a look for me :) 

[Jonathan Kay]

Private Message sent.

Jonathan

[ChrisC]

They are still a classic Mini wiper, or almost every BL car of that era.  The ratio changed (how much sweep they have) but that's about it.  They are all noisy compared to modern car wiper motors, but it's more of a mechanical noise over a grinding.  

The principal is simple, the motor turns a large gear, which basically pushes and pulls a spiral flexible rod.   The rod is in the tube that runs under the dash. In the base under each wiper arm there is a gear that's turned by the spiral rod as it's pulled backwards and forwards by the motor.  The tube is held together by the wiper arm bases which are bolted together. 
They should be lubricanted from manufacturer, with a grease.  I imagine if needed just any general purpose lithium grease would be fine.  
Wiper motor repairs in a 420 are not east given the location, not the complexity of the system. The process will be dismantle the system bit by bit until they work again, then replace as needed (warranty dependant).  For example remove the arms, are the splines now turning, or is the rod moving in and out.

There was a bad batch of wiper arms sometime in 2019, where the arm wasn't a good fit on the spline, resulting in wipers that made a horrendous noise but didn't move, or feel off.  My car had them, one feel off at the end of the wiper test during IVA, the other departed the car on the motorway soon after.  Replacement arms where the fix, supplied under warranty.