Richard454
Well-known member
After driving the past two Hotrod Power Tours - 3000 miles in a week on my mostly original 73 coupe. There were a few things I felt were more a need that a want-
Working AC, overdrive trans and delay/intermittent wipers!!!
The wipers are really not that terribly tough to add a delay- but haven't really found one I like or thought it could be a lot better.
The two I have seen-
First the simple "555" timer board has been used- but since there's no way to "read' the location of the arms-they will stop at different positions each time. Sort of makes the modification half-baked - especially true if you add a wiper door in the mix. Cost- simple board found on the internet from $20 to a "packaged unit" for under a $100.
Second solution is using the late C3's intermittent wiper set-up. There have been a lot of issues w/ the 40 year old technology- pretty telling is that you can buy a harness to bypass the bad module!!! Not to mention the less than accurate delay cycles. Until recently, the replacement boards were unobtainable- now are new solid state boards- however you must find a used cover to control the intermittent wipers - new switch and place to put it- the wiper motor set-up - and if you have a pre-75 you'll have to add an outboard washer pump set-up plus wiring and connectors. So the cost- easily over $300 probably closer to $400.
Harness to BYPASS non-working intermittent wipers!!!
Here's my solution-
Late 90's GM wiper motor w/park- wiper switch controller and your old wiper motor. Getting these at your local Pull-A-Part about $35. On eBay less than $75-100.
I wired the "new" motor to it's controls-it worked great- NO external modules needed- all the electronics are in the wiper cover.
What it does-
- mist -turns on-sweeps once and parks
- wash -operates pump for a couple seconds wipers sweep twice and park
- 5 delays (30 /15/8 /4 /2 /1sec) Sweeps once and doesn't park till turned off-
- low and high speeds.
Originally I was just going to use all the new stuff- replace the motor, switch and new wiring.
HOWEVER-
Could get the new motor to fit-even had same size stud for the arm. BUT the new motor was "clocked" differently- as the motor would have to be horizontal to park the blades correctly....bummer.
Line up the motors- and the park is in a different position- won't work!!!
Have to cut up the firewall for it to park correctly....
Plan B-
Use the old -dual field shunt speed controlled negative switched motor w/ the new electronics that were positively switched. Plus use the new cover on the old motor to so the electronics would "see" where the wiper arms were. That required swapping out the park solenoid switch as well to work w/ the new board.
I was able to make everything work-has to be a 73 or later motor case-because of the size of the park switch/solenoid- AND 68-72 w/ the wiper door controls can easily be added to the new electronics w/ a relay. I did have to use two Bosch (SPDT) relays to change the polarity and switch to high speed. But everything works as it should.
Hopefully will fit one in my 73 this weekend- next step is incorporate the stock push function to operate the washer and just add a rotary knob to control mist/delays/low and high speed. Thus everything will pretty much look stock but operate like what's found on newer cars.
BTW- I have a rain sensor board to try out on my 71. YES- you heard me correctly -uses an optical sensor...turns the wipers on when it senses rain!!!
[ame]youtube.com/watch?v=gM_dO041chM[/ame]
New cover versus old pump cover- will have to add a washer pump pre-75
park solenoid through the years- 69-72 73 and the late 90's
Wiring- for testing- will use weather packs on the car. Power & ground- just run the harness and not use factory stuff. Blue and red wires operates washer pump.
The controls-just add knob
almost finished- some minor work needed to seal it up-
The "Rain Sense" board- note eight wires versus 6
Working AC, overdrive trans and delay/intermittent wipers!!!
The wipers are really not that terribly tough to add a delay- but haven't really found one I like or thought it could be a lot better.
The two I have seen-
First the simple "555" timer board has been used- but since there's no way to "read' the location of the arms-they will stop at different positions each time. Sort of makes the modification half-baked - especially true if you add a wiper door in the mix. Cost- simple board found on the internet from $20 to a "packaged unit" for under a $100.
Second solution is using the late C3's intermittent wiper set-up. There have been a lot of issues w/ the 40 year old technology- pretty telling is that you can buy a harness to bypass the bad module!!! Not to mention the less than accurate delay cycles. Until recently, the replacement boards were unobtainable- now are new solid state boards- however you must find a used cover to control the intermittent wipers - new switch and place to put it- the wiper motor set-up - and if you have a pre-75 you'll have to add an outboard washer pump set-up plus wiring and connectors. So the cost- easily over $300 probably closer to $400.
Harness to BYPASS non-working intermittent wipers!!!
Here's my solution-
Late 90's GM wiper motor w/park- wiper switch controller and your old wiper motor. Getting these at your local Pull-A-Part about $35. On eBay less than $75-100.
I wired the "new" motor to it's controls-it worked great- NO external modules needed- all the electronics are in the wiper cover.
What it does-
- mist -turns on-sweeps once and parks
- wash -operates pump for a couple seconds wipers sweep twice and park
- 5 delays (30 /15/8 /4 /2 /1sec) Sweeps once and doesn't park till turned off-
- low and high speeds.
Originally I was just going to use all the new stuff- replace the motor, switch and new wiring.
HOWEVER-
Could get the new motor to fit-even had same size stud for the arm. BUT the new motor was "clocked" differently- as the motor would have to be horizontal to park the blades correctly....bummer.
Line up the motors- and the park is in a different position- won't work!!!
Have to cut up the firewall for it to park correctly....
Plan B-
Use the old -dual field shunt speed controlled negative switched motor w/ the new electronics that were positively switched. Plus use the new cover on the old motor to so the electronics would "see" where the wiper arms were. That required swapping out the park solenoid switch as well to work w/ the new board.
I was able to make everything work-has to be a 73 or later motor case-because of the size of the park switch/solenoid- AND 68-72 w/ the wiper door controls can easily be added to the new electronics w/ a relay. I did have to use two Bosch (SPDT) relays to change the polarity and switch to high speed. But everything works as it should.
Hopefully will fit one in my 73 this weekend- next step is incorporate the stock push function to operate the washer and just add a rotary knob to control mist/delays/low and high speed. Thus everything will pretty much look stock but operate like what's found on newer cars.
BTW- I have a rain sensor board to try out on my 71. YES- you heard me correctly -uses an optical sensor...turns the wipers on when it senses rain!!!
[ame]youtube.com/watch?v=gM_dO041chM[/ame]
New cover versus old pump cover- will have to add a washer pump pre-75
park solenoid through the years- 69-72 73 and the late 90's
Wiring- for testing- will use weather packs on the car. Power & ground- just run the harness and not use factory stuff. Blue and red wires operates washer pump.
The controls-just add knob
almost finished- some minor work needed to seal it up-
The "Rain Sense" board- note eight wires versus 6
