1966 2-Speed wiper motor question

[GtgBevitt]

Hi everyone,

I’ve converted my ‘66 coupe to RHD, and I’m having trouble getting the wipers to sweep correctly.
Originally I thought it was a problem with where I relocated the motor, but what I’ve found is that the “park” location of the motor is further down the windscreen than when the motor is operating.

I have the park location correct, and at full sweep is good (parallel with the a-pillar). It’s on the downsweep whilst operating that only wipes to about 45degrees, rather than right back down to the bottom of the screen.

I’ve pulled off the cover and inspected all gears, everything appears to be working correctly.
I suspect it might be a length issue of the linkage (because I’ve converted to RHD might need modification), but with the max sweep and park location correct, I didn’t want to throw that out.

Any suggestions would be much appreciated!

[jiffy]

Just to confirm how this is operating:

Wipers are low on windscreen at park, turn them on and the up-sweep covers the full windscreen, but the down-sweep only reverses to about halfway, then goes back to full-sweep position, then this cycles until you turn the power off?

When you turn the wipers off, the wipers return to their position low on the windscreen? Or do they stay mid-sweep?

This to me sounds like you have an electrical problem within the wiper motor. The motor is returning halfway before re-energising (possibly in reverse) for another upsweep, then this continues until the power is removed from the motor until it returns to the park position. You may need to check your wiring.

[GtgBevitt]

You’re correct, and when I turn off the wipers, they return to their position low on the windscreen.

Thanks for your input, I’m thinking something similar about the wiring, and will go down that path

[jiffy]

ok - this might help a little. Here's a write-up on how to fix the park feature.
https://forum.mustang.org.au/index.php/topic,36877.msg340777.html#msg340777
It's not exactly the issue you're having, but it might help you to understand and visualise the internals of the wiper motor.
You should be able to disconnect the wiper mechanism and ensure that the wiper motor is turning full circle (the park feature working implies that it does), you'll see the two brushes that rest on the armature at 180 and 135 degrees that allow the two speeds to operate at two speeds.
You sure have an interesting issue to fix - I would try to establish whether the motor is turning a full 360 degrees (which would make it a mechanical problem) or it it turns and then reverses (an electrical problem)( - then try disconnecting the wiper mechanism and see what it does, then try a known good wiper motor without the mechanism connected just plugged into the harness.

Try a process of swapping until you find the root cause...

Good luck

[big al]

Your problem is in the arm that bolts to the motor.
It needs to be modified