Wiper motor retrofit question

[zachmac]

I am trying to retrofit a VW Bosch wiper motor (ala James Seabolt post on Miafiori). I have that write up and good wiring diagrams of my 80 FI spider. BUT, the Bosch motor I have has slightly differnt wire color codes than the one in Seabolt's writeup. In trying to figure out how to wire it I have a few questions:

The existing six wire setup runs to a large extent through the intermittent relay. That relay is shown as a "black box" on the wiring diagrams. I need a diagram of the inside of the intermittent relay or a verbage write up of the four wires connected to it as far as what does what. Anyone got such a thing?

Also, couldn't help but notice on the stock harness that the Lt. Blue / white trace wire on the red connector (C14) doesn't need to connected for everything to still work fine. The stock Marelli motor works in slow, fast, intermittent and parks fine with or without it plugged in?????

BTW, the Bosch unit rotates about 160% faster than the stock unit so I want to make this work. It has five wires, brown = ground; green / yellow = high speed and soild green = slow speed . BUT I cannot figure out a combination of connections for the remaining black and green / black trace wires on the Bosch unit to get it to park.

[aj81spider]

I ran into a similar problem when changing out my wiper motor. I just took the cover off the gear box on both and traced the wires - rewiring the new one to make it look the same. That was simple as there was only one wire connected differently. On my 81 the wires coming out of the starter motor are:

Light Blue and Gray go to the brushes in the motor. I believe light blue goes to the fast setting brush (red coming out of the motor to the solder lug) and gray goes to the slow (green coming out of the motor) - but I am relying on scribbles from several months ago for that.

Black is connected to the motor chassis and is ground.

There is a switch that is moved by a cam that lets the motor run until it hits the parked position (the cam opens the switch). The common of the switch is connected to gray-black. the Blue-white goes to the normally open contact and the Blue-black goes to the normally closed (again relying on old scribbles - so may be backwards - check your motor).

On the new 5 wire motor one of the two contacts (I forget which one, but seems likely that it was the normally open) was jumpered to ground. I unsoldered that connector and ran a new wire to make the new into a 6 wire configuration that plugged right into the car. I also had to clip the connectors off the old motor and solder them onto the new motor because the connectors were different.

Although that didn't directly answer your question I hope it was of some help.

A.J.

[zachmac]

AJ Thanks for the reply. Couple of more questions as I am still confused:

I'm still confused on how I end up with 6 wires. Currently the bosch has a green and a red wire to the motor windings (slow and fast speeds) and a brown ground wire. The clearly correspond to the same three wires on the stock marelli motor hookup.

That leave two wires running into the gear housing that do indeed make and break contact to ground momentarily as the motor rotates (a white and a blue wire on the VW motor I happen to have) In addition, there appears to be a connection internally that comes out of the gear drive housing through the insulated connector block that goes to a tab bent over to connect with the body of the motor.

My particular Bosch motor has the cover to the gear housing riveted on so I am trying to do this without having to open it up and then have to tap the rivet holes for screws. Is it possible I can do what we are talking about by simply bending the external tab that grounds the "sixth" point to the body away and make my sixth wire connection there?

Not sure any of this makes sense without a picture?

[zachmac]

I think re-looking at Seabolt's article I have my answer which is NO, I don't have to open the cover. I think the connection to ground is via a tab from the internal finger that comes up through the plastic "pass through" and bends over to contact the body. Looks like if I just dremel that tab loose from the body and bend it up I can simply add a wire there and then wire it up as per Seabolts article. It certainly won't do any harm to cut the tab and bend it up and then I will know by running the motor if the ground connect is gone and the open close between the two wires and the new wire still works.

[aj81spider]

If the tab does break with ground and you can solder to it without opening up the housing make sure you shrink wrap it and insulate it well so it doesn't vibrate back into a short.

[spider2081]

For what it is worth the Fiat Spider 200 Electrical Diagnostic Manual 1980-1981 states "If wipers only make one sweep and stop: Check for continuity from C13, through the park switch to LT BLU/WHT wire of C12.
Looking at the wire diagram it appears to me the wire is there to reset the delay timer. Once the timer times out the wipers should sweep again and park. When they reach park I think a sort duration positive voltage resets the the timer for the next sweep. I did not try disconnecting the wire on my car to see if everything works as you did.
Certainly the book could be incorrect.

[zachmac]

I simply separated the "shorting tab from the cover and soldered on a sixth wire there. Hooked it all up per James Seabolt's article and it works like a champ! I just need now to splice it to the stock motor harness and I'll have a plug and play setup. Hopefully whenb I am all done I'll also have useable wipers!

[grittracing]

who make a wiper motor that the arms criss cross that i think is the same length apart as our spiders ?

[spider2081]

For what its worth I did this yesterday
My wipers were soooo slow they were practically unusable. I checked the mechanics for binding and re-lubed and made sure all was free. Then checked the voltage at the motor windings. I was only getting 8.5 volts to the motor. So I traced the the circuit and found many small voltage losses. The greatest was at the fuse connections. I cleaned the connections as best I could but still there was some loss.
I bought an inline fuse holder, installed a 10 amp fuse and connected the fuse holder directly to the alternator output. I looked up under the dash by the ignition switch and found the gray/black wire that feeds the wiper speed switch in the center dash. There was just enough slack in the wire about 8" to fold it in half and cut in the middle. I connected the side that comes from the steering wheel switch to a Bosch Auto relay coil. The other side of the coil to ground. I routed the new fused wire through the firewall to the same area and connected it to the normally open contact on the relay. I connected the other half of the gray/black wire to the relay contact common. Now the wiper motor power for both high and lo speeds comes directly from the alternator/battery and the motor operates with the same hi/lo delay and park that the original configuration has.
Wiper fast speed is now to fast unless there is a full down pour. I am amazed at the speed the wipers have in the fast position.
So for me retrofitting a different motor would not be worth it right now.

[124JOE]

i see youve only owned it a few years.
so ,ill just say the frist week igot mine, i stripped one for parts
after 3years, i stripped 2. IDK if you could pick up a parts car ?
they have saved me over and over again.
but with the parts online we're all ok.
not like some other cars without parts.