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MG MGB GT V8 Factory Originals Technical - wiper motor runs backwards

I now have around 250 miles on the Buick 300 BGT, and as it was raining a bit thia AM, I discovered a problem with the wipers. They want to wipe the bgonnet, not the glass. Not too effective. On a GT with 2 wipers, the blades park on a counter clockwise sweep, looking from the drivers seat. My wipers park on a clockwise sweep. Although I thought I used a GT moter/cable/arm setup, It acts like a 3 wiper roadster.

How to fix this? As far as I know, all the motors (2 speed) are the same. Are there different park switches? I don't see any differences in wiring.

Since the cable, wheel boxes & tubes are correct & in place, I do not want to change them if I can avoid it.

Good suggestions?

Jim Stuart

Maybe you have the wiper boxes in backward. When sitting in the car, the side of the wiper box that has the post sticking up for the wiper arm should be closest to the engine bay, and the side that has the opening for the gear should be closest to the driver and passenger seats.



Sounds like the cam for the parking switch is in the wrong hole in the drive gear, it can be fitted 180 deg. apart and if ‘wrong’ gives the symptoms you describe. Remove the gear cover, disconnect the drive and remove the gear, on the back side there is a plastic cam which operates the parking switch, pull the cam from one hole and replace it in the other.

Geoff King

I actually did this to make the wipers park on the other side, it is the small plastic cam. Or just point your wipers to park on the other side.

Doesn't matter if the motor runs backwards or not since it parks at an extremity of movement hence no matter which way the motor turns the rack will move in the same direction. Neither does it matter if the cam is 180 degrees out on the gear wheel, that will just make it park on the other side. If they are sweeping the bonnet and the wheelboxes are correct you have put them on the spindles incorrectly i.e. on the wrong side of the screen. Put them on the spindles while parked on the 'wrong' (for you) side, then alter the cam to get them to park on the side you want.
Paul Hunt

And the WINNER is Geoff!!

Thanks to all who responded. As far as I can tell, there is no way to install the wheel boxes incorrectly, as the drive stem must go through the hole in the valance below the windshield, & if installed backwards, would have to be outside the car. Maybe we are just not communicating on this item.

After disassembly, I find the metal gear with a drive pin which parks closest to the cable end of the gear box. It must park there because of the hump on the plastic backing that depresses the pin on the park switch. I removed the gear & plastic backer, carefully pryed the plastic back so I could rotate it 180', & this made the gear park in the rear of the gear box. Reassembly & reinstall the wiper arms & all is well.

No idea how things got screwed up, as this was the original wiper assembly, as it turned out, & had never been disturbed, as far as I can tell. Perhaps it was the extra 4 cylinders driving the alternator....

Jim Stuart

This thread was discussed between 30/07/2003 and 31/07/2003

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