Wiper Motor Repair Guide

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Re: Wiper Motor Repair Guide

Post by Taggers » Sat Jan 07, 2012 6:59 pm

Cheers Piers,

The problem is, the fault originally showed up on a new replacement switch (or maybe before, that may be why I replaced it, to be honest I can't remember!), now I swapped it for the old one again, but the symptoms didn't change. Perhaps I'll put the new one back in.

All a bit desperate.


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Re: Wiper Motor Repair Guide

Post by piers.morrell » Sat Jan 07, 2012 7:15 pm

Could be the park switch on the wiper motor giving you grief, you can get it off without removing the motor, give it a good clean refit and try again. Available from svc for £11 off the top of my head if you need a new one. Took me a fair while to sort mine so I understand the frustration!


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Re: Wiper Motor Repair Guide

Post by tony.idle » Sun Jan 08, 2012 12:35 am

Other than the delay unit possibility the symptoms suggest the parking switch isn't operating. Unclip it from the motor & operate it manually. The wipers should stop. If they do the switch or the ramp/cam on the back of the drive gear is worn - or the circlip has come off the external end of the drive gear shaft.


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Re: Wiper Motor Repair Guide

Post by scimjim » Sun Jan 08, 2012 10:21 am

if you don't have power at the G/W parking feed - where is the motor getting its power from when you turn them off? you must have a wiring problem or internal problem in the motor?


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Re: Wiper Motor Repair Guide

Post by Taggers » Sun Jan 08, 2012 2:46 pm

Gah.

More later.

I suppose it's stupid to ask if anyone's got a column switch?


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Re: Wiper Motor Repair Guide

Post by tony.idle » Sun Jan 08, 2012 4:35 pm

Does this help? It's one I drew out to explain 5a wiper operation for someone on Yahoo a while back. Whilst the physical appearance of the switch and an odd wiring colour may be different the principle (once you remove/ignore the delay unit) is exactly the same. Notes: the wiper always parks using the low speed circuit; the park switch removes power and short circuits the motor to brake it; the contacts of the park switch are shown on the drawing detached from their housing/connector block for clarity.
Attachments
5A Wiper.jpg


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Re: Wiper Motor Repair Guide

Post by scimjim » Sun Jan 08, 2012 5:22 pm

the text refers to LG but has G on the diagram Tony.


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Current: SE5 (8Ball), TI SS1 (snotty), 1600 SS1 (G97), 1600 SS1 (C686CCR), 2.5TD SE5a (diesel 5a), 6 x random other SS1s.
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Re: Wiper Motor Repair Guide

Post by Taggers » Sun Jan 08, 2012 6:19 pm

Cheers all. what a pain!

Ok, here's where I'm at. I found evidence of burning at the wiper fuse. I was fairly bad, so I've clipped the wires off the fusebox crimped in an inline fuseholder. Not great, but works until I fit a new fusebox.

At the motor end, the B/G crimp just fell off, so I've remade that.I cleaned about a trunnion's worth of grease out of the gearbox. After a load of fiddling I think the column switch checks out ok.

I get the same symptoms with the new and old motor switch, so I think that must be fine.

The result is:

Ignition on, switch on wipers, they go really fast. "Slow" and "Flash" (you know what I mean, down) seem to be the same speed (V fast). "Fast" is a bit slower!

If I have the motor switch in my hand, the button on it stops them (they don't seem to want to park).

With everything bolted up , once they are on, they stay on. If you turn the ignition off or unplug them and plug them back in, they will (usually) stop- and then park!

The nib on the motor switch is the same length on both switches, and doesn't look unduly worn.

I think, like Jim, it must be internal to the motor, so a new brush plate should sort it (would a worn or stuck brush, do this?)

The other possibility, I suppose, is a worn out ramp on the wheel, but it didn't look bad, certainly not across the length of it. I see there are various wheels available, does anyone know the right angle?


Chris.


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Re: Wiper Motor Repair Guide

Post by scimjim » Sun Jan 08, 2012 6:41 pm

have you checked which wire is live when you turn the switch off? it must be your fast speed wire (not sure of colour on a 6) which is getting power all of the time - where from?


Jim King

Current: SE5 (8Ball), TI SS1 (snotty), 1600 SS1 (G97), 1600 SS1 (C686CCR), 2.5TD SE5a (diesel 5a), 6 x random other SS1s.
Previous: SE5, 3 x SE5a, 2 x SE6a, 3 x SE6b, GTC, 2.9i GTC, 3 x 1600 SS1, 1300 SS1, Mk1 Ti Sabre, Mk1.5 CVH Sabre
Chief mechanic for: 1400 K series SS1 (Megan3), 1400 CVH EFi SS1 (Grawpy), Sabre/MX5 auto (The Flying Broomstick),
1300 SS1 (Number One) & Sarah's coupe.
CURE THE FAULT - NOT THE SYMPTOMS

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Re: Wiper Motor Repair Guide

Post by Gemini Bob » Sun Jan 08, 2012 6:50 pm

Chris does it have an intermittent control and if so have you removed it by just joining the connectors together to discount it?


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Re: Wiper Motor Repair Guide

Post by Taggers » Sun Jan 08, 2012 6:54 pm

It hasn't got an intermittent, Bob.

That would make sense Jim, sadly I'm now too frazzled to remember, and it's too dark to check.

Chris


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Re: Wiper Motor Repair Guide

Post by Roger Pennington » Sun Jan 08, 2012 7:20 pm

Taggers wrote: The other possibility, I suppose, is a worn out ramp on the wheel, but it didn't look bad, certainly not across the length of it. I see there are various wheels available, does anyone know the right angle?


Chris.
The gear should be a 130 deg one (it should be stamped on the front face).


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Re: Wiper Motor Repair Guide

Post by tony.idle » Sun Jan 08, 2012 8:34 pm

Jim

There's another mistake as well: ULG = blue/light green not black/light green. However I hoped the drawing might help understanding of how they work. Once that's understood faulting becomes easy.


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Re: Wiper Motor Repair Guide

Post by tony.idle » Sun Jan 08, 2012 8:44 pm

Incidentally there is nothing inside the motor that would make it do this other than (possibly & I haven't thought it through) an electrical problem. Certainly not the brushes or armature (which together with some magnets comprise the motor).

If you operate the parking switch in your hand and the motor always stops (quite abruptly) with everything else fitted then the fault is, quite simply, that the motor gear for one reason or another is not operating the parking switch. Operated in this manner the wipers obviously won't park because you have the device that determines where to park in your hand.


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Tony

Embrace your feminine side - RTFM

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Past: 2x5A, GTC. Current: SST, Smart, Hymer Motorhome, Rialto, Robin, Bug, MZ Skorpion x2.

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Re: Wiper Motor Repair Guide

Post by tony.idle » Sun Jan 08, 2012 8:47 pm

Jim

There is always power to the motor when the ignition is on regardless of the column switch position.


Regards

Tony

Embrace your feminine side - RTFM

RSSOC 2332 since 1981
Past: 2x5A, GTC. Current: SST, Smart, Hymer Motorhome, Rialto, Robin, Bug, MZ Skorpion x2.

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