Porsche 911 Rear Wiper Switch to Fan Motor

[Bookd]

I have upgraded to the Elephant Racing 911 front mounted oil cooler. In the book 101 Projects for your Porsche 911 by Wayne Dempsey it is suggested that you use a rear wiper switch to start and stop the fan motor. My question is how do I wire the 4-pronged rear wiper switch that I just purchased from pelican parts. My car does not have the rear window wiper. Thanks.

[Luccia at Pelican Parts]

Bump! Post was in moderation, so want to get your question back to the front page. Any Pelicanites have some input for him?

[86 911 Targa]

If your new oil cooler has a bung, install the factory temp sensor
in conjunction with a relay and a fuse.

pm me as needed.

Best,

Gerry

[Koizumi]

Originally Posted by Bookd

I have upgraded to the Elephant Racing 911 front mounted oil cooler. In the book 101 Projects for your Porsche 911 by Wayne Dempsey it is suggested that you use a rear wiper switch to start and stop the fan motor. My question is how do I wire the 4-pronged rear wiper switch that I just purchased from pelican parts. My car does not have the rear window wiper. Thanks.

I’m wondering if you’ve figured this out.

[darrin]

this kinda helps a bit Question on rear wiper switch 91161332101

Seems the key is to bench test it with a test light to determine which connectors toggle on/off with the switch and then use these connectors to trigger a relay instead of directly handling the current going to the motor.

edit -- here's another -- Rear wiper help Needed

Sounds like terminals 53 and 53a are the ones to try first, as that looks to put the switch between the fused power and the motor

[jamesrg]

I used this link to wire my switch.

oil cooler fan t'stat and switch installation

Tapped into the grey wire in the trunk, ran a wire to the switch. Ran another wire from the switch to a bolt on a trunk bolt hinge. Flip the the switch up fan acts as normal, flip the switch down and the fan comes on. I think I used the top two terminals on the switch.

[tirwin]

My car has an oil cooler fan wired to the rear wiper switch by a previous owner. My question is, why not either wire it to run constantly or just leave it on all the time? It’s much easier to prevent high oil temps by running the fan BEFORE you really need it rather than turning it’s on AFTER you have high oil temps.

[jamesrg]

With my setup you could flip the switch so it is on all the time. But I rather not have the fan running all the time. Wear and tear on the fan I guess, in the winter there is no point in having the fan on at all. I rarely get above 210 in the winter. In the summer I switch it on when it gets above 210ish boil out the water in the oil (high humidity in Houston) and it takes 5min or so and it drops back down to 190ish. As long as I am moving it stays in the 210 range, but if I get caught in traffic and the middle of the summer 2 things happen. 1. I start baking 2. the car temps start to climb. So if that happens I flip the switch on if I encounter traffic and keep the temps around 210 for peace of mind. Just the way I do it, seems to work for me.

[Koizumi]

You guys are awesome, thanks!

[tirwin]

Originally Posted by jamesrg

With my setup you could flip the switch so it is on all the time. But I rather not have the fan running all the time. Wear and tear on the fan I guess, in the winter there is no point in having the fan on at all. I rarely get above 210 in the winter. In the summer I switch it on when it gets above 210ish boil out the water in the oil (high humidity in Houston) and it takes 5min or so and it drops back down to 190ish. As long as I am moving it stays in the 210 range, but if I get caught in traffic and the middle of the summer 2 things happen. 1. I start baking 2. the car temps start to climb. So if that happens I flip the switch on if I encounter traffic and keep the temps around 210 for peace of mind. Just the way I do it, seems to work for me.

I see your point but then wouldn’t it make sense to rig a thermostatic switch to come on at say 210? I just prefer the automatic approach. One less thing to think about... but it’s probably splitting hairs.

[mo-mon]

I also used ianc's thread as a reference on installing a rear wiper switch for my oil cooler fan-Thanks ianc!
Left the stock thermostat as I was lazy to replace it with the BMW part.

[86 911 Targa]

Originally Posted by tirwin

I see your point but then wouldn’t it make sense to rig a thermostatic switch to come on at say 210? I just prefer the automatic approach. One less thing to think about... but it’s probably splitting hairs.

^^^^^
Yup,

Here is what I used.

210f-On

197f-Off

Gerry

[tirwin]

Awesome, Gerry! I’m adding that to my to-do list.

Do you have a source for the thermostatic switch?

[86 911 Targa]

Nason is the name of the company.

https://www.nasonptc.com/
^^^^^
Just call them & tell them what you need.

As mentioned I used:

197f-OFF

210f-ON

You will also have to add a relay at the fuse panel.

Gerry

[darrin]

Originally Posted by 86 911 Targa

Nason is the name of the company.

https://www.nasonptc.com/
^^^^^
Just call them & tell them what you need.

As mentioned I used:

197f-ON

210f-OFF

Gerry

Gerry -- think you have it backward on the above -- 210 ON and 197 OFF, right?

[86 911 Targa]

Originally Posted by darrin

Gerry -- think you have it backward on the above -- 210 ON and 197 OFF, right?

Spot on!!!!

Post corrected.

Thank you.

Gerry