O.K.? What's the secret about wiper motors?

[SBPage1]

I have a 1988 C3500 w/7.4. Been having the same issues with wipers working sporadically. Went to local parts store and bought some Dielectric Grease and some Contact cleaner. Took module out, cleaned the contacts on both ends of module, put dielectric grease on contacts at both ends, as well as running a piece of sandpaper across the contacts that look like points. Reinstalled module and it works like a champ!

Antiquated system for sure. Give the cleaner and gel a try!

[mountie]

Good job,,,,, I did the same "band-aid fix" ( no offense).... It will fail again.

Do what I did.... get a '95 wiper motor. Bolts up same as the old one.

[abig84]

Originally Posted by mountie

The symptoms start slowly. As you turn on your wiper, it could do a number of things:
A split second pause to react.
Will turn on but will stop/start once in a while.
It only works on fast mode (most often does this).
Turn off ..it won't stop at bottom... you have to "time" the off so it stops at the bottom.
Won't turn on at all....... THEN it turns on whenever it wants - off whenever it wants.
(You start to worry)
Bump the wiper motor with screwdriver handle to turn on ( fast mode only)

Wished you looked for the "&%$@*&" part sooner.

my 1990 had the same issue. so i figured it was something with the circuit board because if i pulled on the plastic parts it would usually start working fine. so about 5-6 years ago i shoved a bolt between the plastic part of the motor and the firewall... worked fine ever since

i do have a back up one though that came out of a 1991 (hopefully its the same) if it ever goes out but so far that temp fix has held out

[mountie]

Yea... What I enjoy about my older truck is it is cheaper & kinda fun working on it. I also like to improve/upgrade it as stock as possible.

If I had to upgrade my wiper motor again, it would take 45 minutes or so.

also put a new switch in the steering coloum. The turn signal lever is just the "knob".... the actual switch is inside. That will wear out.

[SBPage1]

All great inputs and I will remember these as I deal with this module. Temp fix for now and when I get time I'll look into a new wiper motor with different module. The big block in this truck generates a lot of heat and I can see all my working drying up soon.

Thanks for the help

[metalman]

Cracked solder joints was mentioned back earlier in this post. Here is a pic of what that looks like for people. I reflowed them, lets see if i can get another 30 years out of it.
Also there are 3 electrolytic capacitors on the PCB. I plan to replace those as well as they can dry up and can cause problems and usually need replacing every 10 to 15 years. Mileage may vary on that as i have see much older ones still going and have see some only a few years old leaking goo. I always try to fix before i buy. Sometimes it works, sometimes not. lol
This is on my '88 C1500 by the way.

[LT7A]

So glad this thread was revived. Was very surprised to see the comment about it being six years old. How does that matter if the info is still relevant? This is why the search function is there. I have just begun to have problems with my wiper motor and wasn't looking forward to the diagnostic process. I now know where to start. Thanks dudes!

[j0ee]

Hello everyone, I have the same problem and I went with the 40-158 for my 1990 Sierra with the aftermarket built in module and I got nothing. The pulse board began to smoke and I immediately turned in off. I plugged the old one back in and it worked, but I assume that when it gets warm it will begin acting up. Could the 40-158 been defective, I had no luck and am not sure I can get my money back for a replacement to try again. on that 95 is that the same 40-158?

[mountie]

Originally Posted by j0ee

Hello everyone, I have the same problem and I went with the 40-158 for my 1990 Sierra with the aftermarket built in module and I got nothing. The pulse board began to smoke and I immediately turned in off. I plugged the old one back in and it worked, but I assume that when it gets warm it will begin acting up. Could the 40-158 been defective, I had no luck and am not sure I can get my money back for a replacement to try again. on that 95 is that the same 40-158?

I also enjoy keeping my old stuff original & maintained.... But, sometimes, " old is old" & then time to replace.
I replaced my old wiper motor with the newer 85-158... ( as mentioned in earlier post), it swaps exactly the same & now, your maintenance is easier.

You can replace the circuit board from any parts place. ( if needed) ..& about same cost as older " discontinued" style.

[manimal]

There are all kinds of videos on youtube showing how to fix these circuit boards. The "rebuilt" boards are just some yahoo soldiering the cracked joints and sending them out. Save your money and do it yourself.

[j0ee]

Originally Posted by mountie

I also enjoy keeping my old stuff original & maintained.... But, sometimes, " old is old" & then time to replace.
I replaced my old wiper motor with the newer 85-158... ( as mentioned in earlier post), it swaps exactly the same & now, your maintenance is easier.

You can replace the circuit board from any parts place. ( if needed) ..& about same cost as older " discontinued" style.

85-158? Is that the one that worked for you? I might have to look into that one.

[mountie]

Originally Posted by j0ee

85-158? Is that the one that worked for you? I might have to look into that one.

Ask for a 2002 Tahoe ... ( someone told me that & it fit perfect)

others probably are the same, but that's what I did)