Wiper sweep

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Tootall
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Wiper sweep

Post by Tootall »

Hi all,

I have a '63 with clap-hands wipers.

Currently, the wipers are parked just about on the bottom windscreen rubber and sweep up to approx vertical... ie right in the driver's eyeline.

I seem to remember that, before I had to remove the rack and clean out all the old concrete (grease) and likewise with the motor (single-speed) they used to sweep further across the screen, towards the A pillars.

Am I imagining it?

Is there a way of adjusting something to make the rack push and pull a greater distance, so the wipers sweep further?

Or do I need different wiper boxes? I changed mine because the outer nut on one of the old ones had totally rusted on and I could not free it, so had to hacksaw it off.

I have just purchased another replacement set, second-hand, because the rear edge of the bonnet always catches the wipers over the spindle and it never used to before.

The replacements have a different number stamped on them but also catch the bonnet edge.

I see ESM do wiper boxes for clap-hands wipers, which might cure my bonnet-fouling problem - if they're shorter by a few millimetres - but will they do anything for the wiper sweep? Do clap-hands boxes have a different number of teeth, for instance, so that each movement of the wiper rack elicits more movement?

Do I need to reposition the little contact in the 'cup' above the wiper motor? I did try moving it but nothing seemed to change. The sweep was the same and the wipers parked in the same place.

As is so frequently the case with my dear old Minor, I'm clueless...

Does anyone have any good pointers?
simmitc
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Re: Wiper sweep

Post by simmitc »

Two factors affect the sweep: The gear wheel fitted to the motor and the gear fitted in the wiper boxes. Alter either and the sweep changes. They cannot be adjusted as such, only swapped. The modern boxes do not have the correct number of teeth on the gear wheel, hence the different code stamped on them. I identified this issue many years ago and had protracted discussions with several parts suppliers, some of whom no longer trade. In a nutshell their attitude was that they sold what was available and if we didn't like it, then tough. Refunds were made, but they carried on selling the same incorrect units - ever heard the "Nobody else complained, you're the only one with the problem" excuse?

I suspect that you have run in to the same problem as me. I was lucky in that I could refit the original boxes after a lot of cleaning and careful filing of splines and cutting of thread; but if you had to use a hacksaw then you are going to have a problem :-( It's not you, it's incorrect boxes that are causing your problem.

You could try compensating by altering the wheel in the motor. You will need to move the pin that engages with the rack further out so that it prescribes a larger diameter circle as it moves, and therefore pushes the rack further. I'll leave the calculation of how far to move it to someone else. If you can find a couple of scrap motors then you could play around with their wheels rather than risk damaging yours.
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