Wiper Motor Park

[CRBASIN]

My SV wipers no longer park and run continuously (unless I pull the fuse). As I understand from reading old posts, there is a switch inside the wiper motor that opens and breaks the ground circuit when the wipers reach the park position. I removed the end plate of the motor (without taking out the armature), but could not see the switch.

Any suggestions on where the switch is and what it looks like? I am hoping that a simple clean will do the job.

John's Sunbeam "restoration" blog is case you are interested...

 

[Tom H]

The WSM describes the switch in three different wiper motor models , See page 36,37 here:

http://sunbeamalpine.org/wp-content/uploads/2017/10/15-Electrical-System-N.pdf

 

[CRBASIN]

Thanks Tom.

As far as I can tell, the workshop manual explains how to adjust the park position, but does not say how to clean the limit switch. Would the switch be under the domed cover?

John

 

[Tom H]

Opps, I referenced the wrong manual for a SV. Here's the correct link and you need to look at pages 48-50.
http://sunbeamalpine.org/wp-content/uploads/2017/10/15-Electrical-System-N-2.pdf

Assuming you have a 2 speed wiper then the figure on page 48 shows you where the "switch" is. It's a wiper inside the domed cover. See items 2, 5, and 10, in the dwg. That item 10 wipes along the surface of item 5, which connects to ground, except for the segment ( item 2) where there is insulation. But before you do any more disassembly make sure your problem is not in the wiring between the motor and the panel switch. You say the only way to stop the motor is to pull the fuse. Instead, try disconnecting the 3 wires at the motor. That will for sure stop it as one of those wires is the power to the motor. But then reconnect only the GREEN ( 12 V power) wire. If the motor stops, then you will know that the problem is in the wiring from the motor to the panel switch or it may be a bad panel switch.

Tom

 

[Tom H]

Note I edited the previous post to correct an error.

 

[CRBASIN]

Great. This looks very good. The pages you sent in the second post don't seem to be in my WSM. Along with your suggestions, I think I will figure this out.

Thanks Tom.

 

[Tom H]

It's really pretty simple. The Green wire carries power to the wiper. If you then connect the Red/ Light Green wire to ground the wiper should run fast. And if you connect both the Red / Light Green and Brown/ light Green wire to ground it should run slow. and if you connect neither wire, it should run just until it gets to the park position. In these old wires it may be hard to see which wire has the Red and which has a Brown tracer, but it may help to peel back some of the vinyl jacket to see the colors less aged.

 

[puff4]

(Every time I read the title to this thread I keep imagining a very wet recreational area.)

 

[CRBASIN]

Problem solved. Thanks for your help, Tom. After reading your description of the wiper park circuit and studying the WSM pages you sent in the second post, I figured out how park works--the absence of a ground. I think--but cannot prove--that the mystery ground was caused by a short (to ground) at or near the brush connection.