Wiper motor circuit update (photos and video)

[Turbofiat124]

OK guys I know some of you have suggested using a relay to compensate for the
voltage drop across the wiring and switches in the wiper motor system and all
and I'm not saying anybody is right or wrong but I guess sometimes I tend to go
at things differently. I had already started on this project so I wanted to see
how well this device was going to work.

Also there is not much more wiring involved in this step up converter versus a relay anyway.

OK so I finally got my elusive 8 amp circuit breaker from a company called Crimp
Supply. It seems none of the autopart stores sold these circuit breakers below
15 amps. The converter itself is rated at 5 amps which should be sufficient since both the blower motor and wiper motor operate off an 8 amp circuit. I don't know how much current each individual component pulls.

I went back and rewired my converter (to and from) using 14 AWG wire which is
good for 15 amps.

I ran the input and output wires through the grommet on the passenger side then behind the dashboard and to the ignition switch. There are two yellow/black wires that goto the column switch which are connected to the yellow output (15 volts) wire. The red input (12 volt) wire is connected to a wire coming directly off the ignition switch instead of the fusebox.

The reason for using the 8 amp circuit breaker initially was, with the engine was not running, the wiper motor would make one swipe then blow a 7.5 amp fuse. My guess is because the less voltage you feed into a step up converter, the more amps it pulls. But with the engine running, it would not blow fuses.

But the voltage drop was not that low. I tested the voltage with the engine not
running and it was around 12.4 volts and somewhere between 13.5 and 14 volts engine running. I did not test what it was directly at the
wiper motor by the time power went through all the switches and such.

It seems at one time the circuit breaker tripped for a second to two but that
was it. So I may be upgrading to the 10 amp version of this device if this occurs again.

Here are some photos. I found a "cutout" in the cowl which is where I decided to mount the converter which is water proof. I figured it being mounted in a heatsink, it would get plenty of airflow and help cool it.







Here is the video of the wipers on fast speed:

http://s222.photobucket.com/user/turbof ... ort=6&o=35

One thing about it, unlike before when the headlamps and heater motor fan are
switched on, they do not affect the speed of the wiper motor at all. So far I'm
impressed with the result. Also I should point out there is no Rain-X on the
windshield whatsoever. Before Rain-X was a must or the wipers would otherwise
stop and I'd have to help them return to rest.

I have no idea why this video is sideways. I thought I had my phone
in the correct position. I guess not.

Also Photobucket is currently dog knotting my computer
so it's taken me about 20 minutes to paste these photos and the video in this post. I guess
it's time to give into the man and upgrade to Windows # whatever. I've milked
this Emachine computer for the past 10 years! I bought it a couple of weeks
before Christmas in 2005.

[RRoller123]

So if I understand this correctly, you are stepping up the voltage from ~12VDC to 15VDC and applying it to the wiper motor?

Pete

[Turbofiat124]

So if I understand this correctly, you are stepping up the voltage from ~12VDC to 15VDC and applying it to the wiper motor?

Pete

Sort of.

I kind of doubt the wiper motor is actually seeing 15 volts by the time power goes through the column switch and rheostat speed switch. It may be closer to 14.3 or 14.5 volts.

But if it is receiving a true 15 volts then I seriously doubt stepping up a volt or two is going to shorten the life of the motor or intermittent module. I'm using is a Bosch wiper motor from a VW/Audi by the way.

[RRoller123]

From the video there seems no doubt that it is faster than stock!

Pete

[DieselSpider]

Most RV/Camping Trailer Stores should have the lower amperage popup breakers.

[seabeelt]

Certainly faster, but I thought the VW/Audi motor was the upgrade originally posted by James Seabolt. It would be interesting to see a before and after on an original spider wiper motor with your method installed. Just curious do you have and can you post the wiring conversion to go from the spider harness to the VW/Audi motor... ie which wire color to which wire color.

Many thanks

[Turbofiat124]

Certainly faster, but I thought the VW/Audi motor was the upgrade originally posted by James Seabolt. It would be interesting to see a before and after on an original spider wiper motor with your method installed. Just curious do you have and can you post the wiring conversion to go from the spider harness to the VW/Audi motor... ie which wire color to which wire color.

Many thanks

Initially it seemed to be. Here was a video I shot after I installed the Bosch wiper motor.

https://www.youtube.com/watch?v=c5J_LTjM4r8

I don't know why but eventually it seemed it started to drag against the windshield like the Marelli motor. Now if it was coming a torrential downpour, the wipers would work just fine.

Here is a write up I used to have on my webpage:

Since day one, the first thing I noticed about my Spider was it's mediocre windshield wipers. I tried several things to boost the speed of the wipers. Everything from fixing the ground, cleaning/ greasing the motor, linkages, etc. All of this helped but it still wasn't to my liking.

I used a Bosch wiper motor from a 1977 VW Rabbit. I got this particular motor for $9.00 plus shipping. If you decide to look for one of these motors, any motor from a mid 70s VW or Audi up until the mid 80s should work. Just be sure it uses five wires. Also this wiper motor uses a relay style connector so it was easy to wire up. This motor is made by Bosch and bolts right in. However requires a slight modification so that the wipers will park and allows the use of the intermittent wiper function. Also there is an extra bracket on the Bosch motor that needs to be cut off. This isn't the only motor that will work but seems to be the most readily available and without much fuss to modify.

Original Marelli:



Bosch:




I was also able to modify a wiper motor from a Yugo which also works much better than the Marelli motor. But after some bench testing I determined the Bosch motor was the best choice. The original speed of the Marelli motor was 46 RPMs on fast. After cleaning the Bosch motor and greasing the commutator bearing and reduction gear I got 73 RPMs when bench tested! Actual speed on a wet windshield was timed at around 65 RPMs. A significant increase in speed.

I dismantled the motor, and cleaned it in kerosene and repacked the grease around the gear with wheel bearing grease.

The easiest way to put the motor back together is to pull the brushes apart and insert the commutator into the gear head. Then stick a flat head screwdriver between the reduction gear and the screw. This will prevent the magnets in the housing from pulling the commutator out of the brushes.

The Bosch motor uses five wires. The 1979+ Spider uses six wires. Here are the wires coming from the car's harness and their function:

Blue/Black --> Always hot when ignition switch is on
Blue/White --> Hot only when wipers are in constant mode
Black/Grey --> Hot on both slow and fast, constant and intermittent
Blue --> Hot only on fast speed
Grey --> Hot only on slow speed
Black --> Ground


Here's a photo of the Yugo motor with the gear exposed. The Bosch motor is similar.




Notice the fingers on the gear cover. As the motor turns each finger makes contact with a certain spot on the disc. One makes contact all the time. One touches the brass portion of the disc briefly and the other one makes contact most of the time.

On the Bosch wiper motor, the trick was to isolate the finger that is grounded to the body and solder a six wire to it. I took some wire cutters and cut the tab and bent it so that it did not touch any of the other wires or the body of the wiper motor and soldered a green wire to it. When I linked the wires from the car's wiring harness to the wiper motor, I used 12 AWG wire. 14 or 16 AWG is OK.




The color of the wires on the Bosch motor do not correspond like one would expect. From some reason the Germans like to use brown as the color for the ground. Even on my East German Trabant. All the ground wires are brown.

Brown ---> Ground
Red ---> Slow
Yellow ---> Fast
White ----> Hot on fast and slow
Black ---->Always hot
Tab -----> Grounded to the wiper motor's body


Once the tab on the Bosch motor is isolated from the gear cover and a six wire soldered to it, it's just a matter of connecting the wires from the motor to the harness on the Spider.

So it's like this (Bosch motor ---> Spider's harness):

Brown --> Black
Red --> Grey
Yellow -> Blue
White --> Grey Black
Black --> Blue/Black
Tab (new wire soldered to it) ---> Blue white


Here is a photo of the Marelli motor's gear cover removed. These should be the same on all Fiats except for the number of wires used. On five wire motors, one of the contacts will be grounded. So there should be no need to break the tab on the back of the Bosch motor and solder an extra wire.




Notice that one contact is fixed and is attached to a tab which can make contact with two other contacts depending upon the position of the wiper motor. In this position the circuit is being completed "most" of the time. As the cam gear rotates, it breaks contact and makes contact "briefly" with the other contact. On the backside of the gear cover are wires soldered to these contacts. So once you figure out what these wires do on your Fiat, correspond them to the wires on the Bosch motor.

Something else you might notice. The Bosch motor turns in the opposite direction as the Marelli motor! But it doesn't matter once it's connected to the linkage.

Here is a new video I shot demonstrating how the lights and heater fan no longer effect the speed of the wiper motor:

http://vid222.photobucket.com/albums/dd ... fbuq2i.mp4

[AriK]

Great upgrade and very creative! It sure beats the ageing Fiat motors that are physically challenged by a dry windshield. Also, nicely organized workshop you got there Turbofiat!

[Turbofiat124]

Great upgrade and very creative! It sure beats the ageing Fiat motors that are physically challenged by a dry windshield. Also, nicely organized workshop you got there Turbofiat!

Thank you!

Although my garage is a mess. Just the other day I threw about six CRT monitors away. Now that you can buy a used LCD for $20 at the Salvation Army or thrift stores.

I can't believe it just took me almost 25 years to figure this out. And how much effort it took to get the wipers to function like a normal car.

Using the step up conveter might work just as fine on the stock Marelli motor.

Interesting is the wipers on my Yugo work just fine and I've never had to do anything to them to increase their speed. I think one reason is the gear reduction. I think the wiper motors used on Yugos produce more torque so they are less likely to stall (drag). They don't spin as fast but don't stall out like the Marelli motors do.

[seabeelt]

Very nice post, Thanks much

[wop]

Certainly faster, but I thought the VW/Audi motor was the upgrade originally posted by James Seabolt. It would be interesting to see a before and after on an original spider wiper motor with your method installed. Just curious do you have and can you post the wiring conversion to go from the spider harness to the VW/Audi motor... ie which wire color to which wire color.

Many thanks

Initially it seemed to be. Here was a video I shot after I installed the Bosch wiper motor.

https://www.youtube.com/watch?v=c5J_LTjM4r8

I don't know why but eventually it seemed it started to drag against the windshield like the Marelli motor. Now if it was coming a torrential downpour, the wipers would work just fine.

Here is a write up I used to have on my webpage:

Since day one, the first thing I noticed about my Spider was it's mediocre windshield wipers. I tried several things to boost the speed of the wipers. Everything from fixing the ground, cleaning/ greasing the motor, linkages, etc. All of this helped but it still wasn't to my liking.

I used a Bosch wiper motor from a 1977 VW Rabbit. I got this particular motor for $9.00 plus shipping. If you decide to look for one of these motors, any motor from a mid 70s VW or Audi up until the mid 80s should work. Just be sure it uses five wires. Also this wiper motor uses a relay style connector so it was easy to wire up. This motor is made by Bosch and bolts right in. However requires a slight modification so that the wipers will park and allows the use of the intermittent wiper function. Also there is an extra bracket on the Bosch motor that needs to be cut off. This isn't the only motor that will work but seems to be the most readily available and without much fuss to modify.

Original Marelli:



Bosch:




I was also able to modify a wiper motor from a Yugo which also works much better than the Marelli motor. But after some bench testing I determined the Bosch motor was the best choice. The original speed of the Marelli motor was 46 RPMs on fast. After cleaning the Bosch motor and greasing the commutator bearing and reduction gear I got 73 RPMs when bench tested! Actual speed on a wet windshield was timed at around 65 RPMs. A significant increase in speed.

I dismantled the motor, and cleaned it in kerosene and repacked the grease around the gear with wheel bearing grease.

The easiest way to put the motor back together is to pull the brushes apart and insert the commutator into the gear head. Then stick a flat head screwdriver between the reduction gear and the screw. This will prevent the magnets in the housing from pulling the commutator out of the brushes.

The Bosch motor uses five wires. The 1979+ Spider uses six wires. Here are the wires coming from the car's harness and their function:

Blue/Black --> Always hot when ignition switch is on
Blue/White --> Hot only when wipers are in constant mode
Black/Grey --> Hot on both slow and fast, constant and intermittent
Blue --> Hot only on fast speed
Grey --> Hot only on slow speed
Black --> Ground


Here's a photo of the Yugo motor with the gear exposed. The Bosch motor is similar.




Notice the fingers on the gear cover. As the motor turns each finger makes contact with a certain spot on the disc. One makes contact all the time. One touches the brass portion of the disc briefly and the other one makes contact most of the time.

On the Bosch wiper motor, the trick was to isolate the finger that is grounded to the body and solder a six wire to it. I took some wire cutters and cut the tab and bent it so that it did not touch any of the other wires or the body of the wiper motor and soldered a green wire to it. When I linked the wires from the car's wiring harness to the wiper motor, I used 12 AWG wire. 14 or 16 AWG is OK.




The color of the wires on the Bosch motor do not correspond like one would expect. From some reason the Germans like to use brown as the color for the ground. Even on my East German Trabant. All the ground wires are brown.

Brown ---> Ground
Red ---> Slow
Yellow ---> Fast
White ----> Hot on fast and slow
Black ---->Always hot
Tab -----> Grounded to the wiper motor's body


Once the tab on the Bosch motor is isolated from the gear cover and a six wire soldered to it, it's just a matter of connecting the wires from the motor to the harness on the Spider.

So it's like this (Bosch motor ---> Spider's harness):

Brown --> Black
Red --> Grey
Yellow -> Blue
White --> Grey Black
Black --> Blue/Black
Tab (new wire soldered to it) ---> Blue white


Here is a photo of the Marelli motor's gear cover removed. These should be the same on all Fiats except for the number of wires used. On five wire motors, one of the contacts will be grounded. So there should be no need to break the tab on the back of the Bosch motor and solder an extra wire.




Notice that one contact is fixed and is attached to a tab which can make contact with two other contacts depending upon the position of the wiper motor. In this position the circuit is being completed "most" of the time. As the cam gear rotates, it breaks contact and makes contact "briefly" with the other contact. On the backside of the gear cover are wires soldered to these contacts. So once you figure out what these wires do on your Fiat, correspond them to the wires on the Bosch motor.

Something else you might notice. The Bosch motor turns in the opposite direction as the Marelli motor! But it doesn't matter once it's connected to the linkage.

Here is a new video I shot demonstrating how the lights and heater fan no longer effect the speed of the wiper motor:

http://vid222.photobucket.com/albums/dd ... fbuq2i.mp4

.


So if one were to install a relay at the wiper circuit, how would that look? I have a stock rebuilt fiat motor.
It it sooo slooooww

[wop]

So, being only marginally talented, i can't seem to figure out how to add a relay at the wiper circuit, how would that look? I have a stock rebuilt fiat wiper motor. would i need a relay for each hot wire?
It is soooo slooooww

[spider2081]

This is the wire diagram I use. I do not cut the grey/black wire as shown though. I mount the relay on the cross member that the dash mounts to. It mounts in the area above and toward the center of the car from the ignition switch close to the signal light flasher. I remove the gray/black wire from the wiper speed switch and connect it to relay terminal 85. I then fabricate a new #14 gauge wire to connect relay terminal 87 to the post on the speed switch that the grey/black wire was removed from.

hope this helps

[OttawaTom]

I didn't see this thread until I had already installed relays on my wiper circuit. Some interesting ideas so far... Has anybody tried a circuit to step up the voltage to the headlights, over and above any advantage you get with relays?

I have a spare motor/linkage, so my winter project is to clean it up a bit...

I installed two relays: one for slow and one for fast. I re-purposed a couple of spares I had lying about. I installed them right at the motor (once the motor is mounted, the relays will be underneath the bracket).




A couple of advantages to doing it this way is that the original wiper circuit is untouched up to the connector that's attached to the motor, and there are no switches at all between the power and the motor; just the relays. I will just have to add a power connection (with an inline fuse) to the alternator post/solenoid and a ground somewhere (that's the new connector in the photos).

If the circuit isn't obvious and anybody wants it, I can draw it out and post it.

-Tom

[red107]

I did this mod today using a bosch motor from a 79 VW rabbit. Everything works great until I lay the cowling down and tighten it down. No movement from the motor. So something is hung up. I will look at it next weekend.