NA wipers slow

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Discussion

Gad-Westy

Original Poster:

15,085 posts

220 months

Monday 26th February
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My 93 import’s wipers are pretty sluggish and there seems no discernible difference in speed between normal speed and high speed. I’ve taken linkage itself apart and cleaned and regreased it so I’m confident that’s okay. I understand the stalk can cause problems but does that fit with these symptoms? Any way of diagnosing that? And if it’s the motor itself what are the best options nowadays for refurb or replacement. Not keen on just buying a random used one. Thanks in advance.

Belle427

9,741 posts

240 months

Tuesday 27th February
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I would check the ground to it is ok, can make a difference, maybe add a temp one to see if things change.
Weak voltage maybe, if the battery is good try again with engine running and a wet screen to see if things change.
Not heard the switch problem personally, i would think it either works or not.
Im guessing you totally stripped the linkage and cleaned those spindle shafts up?

Gad-Westy

Original Poster:

15,085 posts

220 months

Tuesday 27th February
quotequote all
Belle427 said:
I would check the ground to it is ok, can make a difference, maybe add a temp one to see if things change.
Weak voltage maybe, if the battery is good try again with engine running and a wet screen to see if things change.
Not heard the switch problem personally, i would think it either works or not.
Im guessing you totally stripped the linkage and cleaned those spindle shafts up?
Cheers. I'll try the earth, good plan and easy to check. I did indeed clean and grease the spindles. I actually have two linkages and fully restored one of them to put on the car in the hope it would sort it but it's the same on both. Battery is good and it seems to make no difference whether engine is running or screen is wet. Come to think of it the spindles run at the same slow speed even if the wipers are removed. Unfortunately I do not have a spare wiper motor to test. Since asking the question, I've read a lot about the internal speed controller of the motor being the most likely culprit. Lots of mentions of that on forums but unfortunately no mention of how to repair or where to buy a replacement.

I'm tempted to buy a used one on ebay, install it and then pull the old one apart to take a look as I don't really have a better plan right now. I will try the earth thing and report back if it's a success but I'm not confident.

Risonax

351 posts

23 months

Saturday 16th March
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The speed controller on the wiper motor wears out; there are soldered tracks. There are three different wiper motors used on Mk1s.

Gad-Westy

Original Poster:

15,085 posts

220 months

Tuesday 19th March
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Risonax said:
The speed controller on the wiper motor wears out; there are soldered tracks. There are three different wiper motors used on Mk1s.
Thanks Risonax. Since I last posted on this I did actually take the motor apart and cleaned and regreased everything and I gave the contacts a bit of attention too, bending them up slightly to compensate for wear and making sure the copper tracks were clean. I also swapped the linkage over (again just in case my last refurb had made the fitted one worse. Both those things have improved the situation but I'm still not fully happy. Every now and then, the intermittent wipe will stick mid stroke and generally all settings seem slower than they should but I do now see a distinct improvement between speed 1 and 2. Voltage and earth at the motor seem good. I think I'll pick up a spare motor and try it but I can more or less live with how they are now if I have to.