69Myway

Okay,

Final update on this part of the project. I am no longer able to access CF from work, so I will check and update when I can. Any of you with interest in this mod just e-mail me at home. chrisnikki@juno.com

Here is what you need.

1. A 2" stroke linear actuator from www.uslinear.com ($170)
2. A headlight control module (fits 88-96 Vette, and 87-88 Fiero) Cost new is over $100, but you can get one from the extreme left front inner fender at the bone yard on only the 87-88 Pontiac Fiero for $10 or less. ***make sure to clip out the wire harness at each end about 10" back because you will need those pigtails to hook this up***
3. A normally closed 12v heavy duty relay from radio shack.
4. You will need to punch a larger hole in the firewall where the stock vacuum goes, and fabricate a metal bracket to pivot mount the actuator.

5. Remove you wiper door assembly and grind off the linkage where the stock vacuum actuator pivots on the assembly to where you have only the last arm remaining that is attatched to the main shaft. This is where you will run a bolt through to the head of the electric actuator, and at the other end you will run a bolt through the bracket you made throught the bottom of the electric actuator.

6. Look at your wiper motor. You will notice one thicker wire next to a thinner one going into the wiper motor housing. You need to splice in there with a jumper wire. Leave the factory grounding micro switch alone and make sure it is functional.

7. On the headlight module, connect the two red to 12+ key on, connect the black to chassis ground, connect the white wire direct to one side of the normally closed relay, then run the other side of the normally closed relay straight to 12+ key on power.

8. Run the jumper from the wiper motor to the 12+ coil side of the normally closed relay, and continue to jump it to the yellow wire on the headlight module.

9. Go ahead and connect both the left and right headlight signal wires together so they work together. You don't have to do this as you can use either side, but this will keep you from having extra wires going to nowhere.

10. Run the up/down outputs that you just hooked together to the actuator.

11. Now, test and shim your firewall bracket as needed to get the exact opening you are after.

Here is how it works.

When you turn the wiper on, the power wire straight to the motor gets engergized, but it won't do anything until the ground connects. That same wiper motor wire shoots a signal to the headlight module on the upstroke wire, and through the normally closed relay will trip the constant down stroke force of the 12+ key on signal. At this point the wiper door will swing open, make contact with the factory grounding micro switch and the wipers will run. When you turn the wipers off, the motor has power on it until they park. So, the door will stay open. As soon as the power drops off the motor, that signal dies allowing the normally closed relay to go back closed and thus re-exciting the down stroke side of the headlight module and down the door goes.

The linear actuators are weather proof and have built in micro switches that shut them down at the end of the stroke even though power is being applied.

Just e-mail me at home if you have any other questions.


I have also figured out with the help of my friends as CACC how to convert the old shark to delay wipers and even the trick needed after that is done to keep the wiper door open during the delay cycle. Let me know if you want to know how to do that as well.

mrvette

I did the intermittant windshield wipers about 5 years ago, using a 555 timer and radio shack relay, that part is easy, the hard part is understanding how to hook it up to the vacuum door assembly.....
I need to do this with all junkyard parts to electrify the door assy, all I need is time....;-)))......
You are rong in your assumption of how the motor assy is wired....
the two yellow wires are connected together in the harness, one to the pump circuit, blue gets grounded by pushbutton for pump/washer action, the other activates and feeds voltages into the CONTROLL section of the wiper motor, the motor FRAME is ALLWAYS grounded, the heavy red wite goes to the interrupt switch with +12 on it, and gets killed when door closes.....that is directly in series with that switch on bottom of dach for wiper blade service.....

at any rate, I don't see the need, OFFHAND for the controll board off headlights.....all I see need for, from your description,.....is a DPDT relay in the normally open position when wipers are off, that will feed correct polarity to the actuating solenoid to close door, self limiting by the internal switch you mention....so then turned on, the relay reverses polarity and opens door......OR if the liner motor/solenoid you are using doesn't require polarity reversal to work....that's easier yet, just a SPDT relay and it's done....but that would require 3 wires from the solenoid coil, one to ground, and 2 to the fixed contacts of the relay, the moveable contact to +12, coil activated on.....now to hold relay 'closed' long enough for wipers to close before door is actuated, you need a diode from MOTOR side of +12 to the relay coil input....

GENE

Garys '68

Pure genius!
"built in micro switches that shut them down at the end of the stroke even though power is being applied."
That's what I've been missing. I was thinking about doing the same thing but the actuators I've found didn't have the microswitch and required reverse polarity to bring them back down.
Damn!!!!! I just bought a whole new actuator, linkage, and vacuum lines. All that stuff costs more than the electric actuator you found.
Gary

lbell101

re: I did the intermittant windshield wipers...

OK - I'll bite on that one. You added intermittent wipers to a C3 without them??!!
I NEED this mod. Is there details anywhere?
thanks!

mrvette

IBELL, I did it myself as I"m an old geek, you know, electronics tech/engineer type....so I know how to do chips and all that dip....
now it's easy if you familiar with a 555 timer, if not, forgetaboutit....

I mounted mine in the old original position, after filling in the original holes and then redrilling new ones...for new controll pot, pushbutton for WSW function and switch for high speed....

GENE

lbell101

Thanks Gege!

Looks like I'm in the forgetaboutit catagory!

69Myway

Oops, I must have confused you Mrvette. The wires I was describing have NOTHING to do with the C3 wiper motor. I was describing the wires on the control module. This is in the event some brave soul out there wants to follow in my footsteps, I am saving them tons of time figuring out where the wires go on the headlight control module. Why buy all those relays and extra timers and stuff when you can have it all in one factory tested and proven piece. I have yet to see one go bad, and they are plentiful in the bone yard. Plus, it is fun going to the junkyard and looking for cool stuff.

You need to stop over some time if you are still in the Orange Park area. I have not seen you or your vette in some time.

The problem with just putting a delay (555) timer in the stock C3 (68-77) wiper circuit is you never get a true delay system. That is, a true delay leaves the wipers up on the windshield and will pulse based upon the amount of delay you have requested.

I found a 1982 c/e Corvette and clipped out the entire wiper circuit. Went to G.M. and bought a new delay module. I mounted it in the dash instead of the rear cubby as the 69 has no speakers up there. That also shortened the wires. After that it I was home free.

The big trick was frenching the 82 switch into the center console panel. What I did was mount it facing down and modified the plug ends to clear the upper dash pad.

My photopoint account is down so I can't easily post up pics.

Like I said, just drop me a line if you want more details.

mrvette

69MYWAY, you got to check in, I got my car up on blocks, and doing all sorts of cool poopie...

375-0151.....any evening....most weekends....gimme a call....

GENE