simple wiper question

[datto62073]

well maybe two. i have a 76 K25 GMC, and i would like to have intermittent wipers. is there a retrofit that i can do with out rewiring the whole truck?

also i am having issues with my washer pump. it works kinda. if i mess witht he pump and make sure all the linkages are lined up right it works for one rotation. anyway to fix that???

thanks for the help guys!

 

[bucket]

The simple answer is no, there's nothing simple. The '77 model had optional delay wipers and all you would need is the wiper switch and delay module, BUT that setup is very hard to find and the stuff is prone to failure. The '78 model got an improved setup that works much better and parts are more common, but there is some rewiring that needs done. It requires basically every part related to the wipers besides the wiper arms themselves. If going to that trouble, it's very simple to convert to the later style remote washer pump that works very well.

All in all, it's not a difficult swap, it just takes a lot of parts and it can be time consuming.

 

[datto62073]

parts are not to much of a problem. i work for a parts house. all i need is a list of parts. i can find diagrams, thank god i can read them. i own euro and old japanese vehicles so making things work is not an issue.

 

[bucket]

There's used parts that you need too. The best thing to do is find a donor truck to get everything, then replace whatever is no good (like the wiper motor).

You need the dash switch, wiper delay module, the electrical pigtail from the dash, the wiper motor, the wiper motor pigtails, and also the arm that bolts onto the wiper motor.

Besides splicing in the new pigtails, you need to run one additional wire from the wiper switch to the motor (for the park switch IIRC), and modify the opening in the dash for the switch (different size and slight location change). You can use a wiper motor for an '85-up that has remote washer pump, but it's just a matter of rerouting your original washer pump wires (at wiper) to the washer pump that is mounted wherever you put it. You can also use a factory washer bottle from '85-up that mounts the pump in it.

 

[datto62073]

Sounds easy enough. I would be getting as much I can new though. I am weird like that.

so the parts list as I understand it is as follows....

wiper motor
linkage arm
switch
pigtails both motor and switch
delay module and harness
and a later washer bottle with pump.

anything else is am missing?? And what year would be best for a stock look?

 

[bucket]

The switch and module will come from a '78-'83. The switch is available new, but not the module. The wiper motor and pump/bottle will come from an '85 and later square body.

I had the diagrams at one time that made it easy to convert the wiring, but I have no idea where they are now. If you can't get it figured out, just let me know and I should be able to help.

 

[datto62073]

cool. thanks! i will hit ya up if i cant figure things out. i do appreciate the help

 

[datto62073]

Ok I was able to snag an adjustable wiper switch from an 83 'Burban. I snagged the switch and the box right behind the switch but could not find anything else. Is that it?? I can post a pic when I get home if that would help.

 

[bucket]

Yep, that's the parts. Did you also get the harness connector that plugged into the box?

Then you also need the harness pigtails and linkage arm from the wiper motor.

 

[datto62073]

yeah, clipped it back as far as i could. i couldnt find an 85= truck out tehre at the time, so i havent grabbed that stuff as of yet, i just saw the switch and grabbed it. just wanted to make sure i had the switch stuff i needed.

 

[Silverminer]

The switch and module will come from a '78-'83. The switch is available new, but not the module. The wiper motor and pump/bottle will come from an '85 and later square body.

I had the diagrams at one time that made it easy to convert the wiring, but I have no idea where they are now. If you can't get it figured out, just let me know and I should be able to help.

Good news - the module IS still available through Rockauto, O'Reilly's, and maybe other places as well. The AC Delco part number is D6355A, and the UPC # is 36666288582. I bought mine from Rockauto for a 1980 just a few months ago, and it was over $100 which wasn't much fun but it sure is nice to have everything working again.

 

[datto62073]

Good news - the module IS still available through Rockauto, O'Reilly's, and maybe other places as well. The AC Delco part number is D6355A, and the UPC # is 36666288582. I bought mine from Rockauto for a 1980 just a few months ago, and it was over $100 which wasn't much fun but it sure is nice to have everything working again.

ill look it up when i get to work and maybe pick a new one up. thanks

 

[datto62073]

ok. i now have the parts to do this, i think. heres what i have.

78 intermittent wiper switch with box and pigtail
86 wiper motor and linkage at motor AND to pivots with pig tails
86 washer bottle with pump and pigtail

i have the diagrams that i think i'll need as well. 76 wiring diagram, 78-84 wiper diagram both switch and motor, and the 87 wiper motor diagram. is this all i need? or does someone have a diagram that they made up for just this swap?

next question though, is the black/light blue wire the one i am gonna need to run? and the rest i could splice in?

thanks again, i dont know what i would do without this AWESOME resourse to help me with this beast.

 

[chengny]

Just looking quickly at the two schematics, It appears that you are going to need a pulse module from a 1978 model. To match a 1978 switch up to a 1986 module won't be easy if it can be done at all.

Once you have a 1978 module in hand, it will be a straight forward modification.

The wiring on the outlet (non-switch) side of the 1978 module will be cut and spliced into the 1986 harness (as it leads into the cab from the engine compartment).

On the engine side, set up the 1986 wiper motor and washer pump just as would be found in a 1986 truck.

Here are a couple of wiring diagrams (check my work - I have been sloppy lately):

1986 coming in from the engine compartment:

You must be registered for see images attach

1978 switch/module group and how to cross over to the 1986 harness:

You must be registered for see images attach

 

[bucket]

next question though, is the black/light blue wire the one i am gonna need to run? and the rest i could splice in?

I believe that's what I did. The others were matched up by comparing diagrams and splicing in the new connectors.