Estate rear wiper repair, you dont need to replace it!

[J.R.]

My rear wiper has recently been groaning and giving up after a couple of sweeps but always seemed to come back to life later.

 

I had seen a thread with photos of where the cover was removed and the gears etc greased but cant find it now.

 

Mine was a bit dry but after an initial greasing and refit then a more thorough strip down and lube the motor was still labouring when the blade was in contact with the screen.

 

I bit the bullet and removed the motor assembly and worm drive then removed the rear cap and lubricated both ends of the motor shaft, reassembled, bench tested with 12v direct to motor and its as good as new now.

 

In hindsight the motor probably does not need to be removed, the shaft behind the worm drive can be lubricated from inside the gear case leaving just the motor end cap to be removed, unusually the brushes are at the output end so its safe to remove the end cover and nothing will go flying about, the bushing was dry and causing the seizing, another possibility is grease getting onto the circular tracks for the self park mecahnism creating resistance so its worth cleaning them up and the 2 contacts.

 

The circuit board can be removed allowing direct access to the motor terminals for bench testing.

 

Had I not wasted time on the first 2 removals & refits then the whole job would only have taken 20-30 minutes, definitely worth doing before shelling out £80 or so for a new or second hand motor.

Edited 25 February, 2020 by J.R.

[Vrsburnzy]

Not my thread? Ive done a few now, I’ll always strip and repair before replacing, although the hatchback motor has the water pipe in so I’ve used o-rings in the past to help seal the leaking connection.

[J.R.]

No not that one but I did enjoy reading it at the time and commented.

 

That motor was really Fubar'd!!!!!!!

 

Mine being an estate & not having the water running through it was very clean inside, the grease was still in all the areas it should be and clean, some water ingress & corrosion on the wiper shaft but the real culprit was the motor bushes.

 

needs a few metal tabs bending to get it apart, there is a spring clip holding a wedge shaped plastic thrust bearing, if these are removed you could probably get WD40 into the shaft bush without removing the end plate but its pretty simple.

 

I hate replacing stuff just for an easy life, reading trough threads on here thouands of pounds have collectively been spent on new motors, OK the main dealers are just going to throw parts at a job but we have a choice.

[Guest]

2 hours ago, J.R. said:

I hate replacing stuff just for an easy life, reading trough threads on here thouands of pounds have collectively been spent on new motors, OK the main dealers are just going to throw parts at a job but we have a choice.

 

See, this is what happens when kids no longer play with Meccano.  They grow up not knowing which end of a screwdriver to hold!

[MikeTheThinker]

11 minutes ago, MicMac said:

this is what happens when kids no longer play with Meccano

 

Only the other day I was bemoaning having sold my extensive Meccano set as an early teen; it was a full wooden suitcase-type kit; can't even remember what I bought with the 12 squid I sold it for back in 1966 ...

 

 

[pikpilot]

On the facelift Estate rear wiper motor it is also worth worth looking at the brushgear. My wiper became intermittent then failed to work because the brushes were too tight in the brush holders and no longers making contact with the commutator. As the brushes wear down, the springs behind them are supposed to push them down but they get a point where the reduced spring pressure (because they have already moved a bit) is overcome by the friction in the holders.

A quick clean and a to and fro movement of the brushes to wear the sides away and everything works again.

[Tilt]

15 hours ago, MicMac said:

 

They grow up not knowing which end of a screwdriver to hold!

 

And when they do learn which end to hold some just want to prise open a cash till whilst others just want to stab someone with it.........

[Jigger72]

6 minutes ago, Tilt said:

 

And when they do learn which end to hold some just want to prise open a cash till whilst others just want to stab someone with it.........

 

I don't know how you can bear to leave the house with all these screwdriver-wielding thugs about. Jesus! 

 

The only criminals I've ever encountered with a screwdriver have been plumbers and sparkies … and mechanics. Robbing barstewards 🙃

[harrylime]

Gas fitters/plumbers take the prize for being greedy bar stewards. They think they are better than the other trades and worthy of £100k p.a. plus. And many are just parts fitters with no idea how to diagnose a fault

[Hawthorn654]

Very helpful thread - thanks for sharing  

[russ17]

On 26/02/2020 at 14:19, pikpilot said:

On the facelift Estate rear wiper motor it is also worth worth looking at the brushgear. My wiper became intermittent then failed to work because the brushes were too tight in the brush holders and no longers making contact with the commutator. As the brushes wear down, the springs behind them are supposed to push them down but they get a point where the reduced spring pressure (because they have already moved a bit) is overcome by the friction in the holders.

A quick clean and a to and fro movement of the brushes to wear the sides away and everything works again.

 

Hi,

 

I understand that you have disassembled the motor from the gearbox. I have a similar issue on my estate wiper. I have removed the gears and the CANBUS PCB, now I want to separate the motor from the gear unit. It seems to be held in by four large metal tabs. Bending them away from the body will allow the motor to be separated from the gear box, but a cannot see how the brushes are held in. Do the brushes come out as part of the motor, or do they stay in the gearbox unit?

 

The close up image is the contacts of the motor, after the CANBUS PCB has been removed. The PCB is held in place by two torx screws (one gets removed by removing the cover), then you need to gently lever the PCB up as the motor contacts and the "fingers" which contact the gear, to allow self parking, are located in sockets on the underside of the PCB (last picture).

I wanted to do this to allow direct testing of the motor, without risking damage to the CANBUS PCB. In the image you can see the correct polarity of the motor -  +12 V to the outer terminal and ground to the inner terminal.

 

  

[pikpilot]

You seem to have disassembled the unit more than is necessary or your unit is different to mine.

I found that access to the brush holders and the brushes inside them was quite easy. I moved the brushes back and forth in their holder to wear away the sides of the brushes until they became not so tight.

 

I have repurposed the wiper motor assembly but if time allows, I will take some photos for comparisons.

 

Sorry for the delay in posting but I had not noticed that the topic had slipped over to the previous page. 

[roy@ck]

Hello Everyone,

Sorry that it's a couple of years after this item was posted, but I've just had this wiper motor failure happen on my motor, and hope you may have some further info. Like many a child of the late 1940's I too had a Meccano No.3 Set which is probably why I became an engineer. I have looked at the wiper unit and like russ17 removed the printed circuit to reveal the motor terminals. I tested the motor with a 12v supply and the motor and gearbox unit worked perfectly - so I'm thinking that the problem is with the little circuit board. However, the board itself shows no signs of malfunction. Is this component available as a spare part or replaceable part from an aftermarket source? I have checked the wiring in the tailgate and this is OK, with 12v available at the connector when the ignition is ON and the wiper control in the one click forward position - and the tailgate closed.

Any ideas anyone, your thoughts would be much appreciated.

 

Many thanks, Roy

[J.R.]

Check the wiring in the tailgate bellows, if you are lucky you will find that one of the canbus twisted pair is fractured and making intermittent contact.

[roy@ck]

Hello J.R.

Thank you for your suggestion, I certainly will check the wiring in the tailgate bellows. I'll let you know what I find.

 

Many thanks,

 

Roy

[lejf11]

Hello, have the same problem as described in this thread. 

But my biggest problem now is how do i remove the panel ? i tried some yesterday, and got it to lose from a couple of clips. But it sits rock hard at the end upwards . it´s loose in the back where the closing mechanism is located. 

does anyone have some photos or good explanation on how to lose it? 

 

car model. Superb II Station wagon (3T5) 2.0 TDI 4x4 (170 hk / 125 kW)