jcg928s

Hey guys,

As you all know, I have created different threads about how I went electric on my fans instead of a pulley fan.

Well I am now back to a pulley fan and havent looked back since.


I think the electric fan setup for the early 928s are great (Ford Contour or the Ford Taurus). They move some serious air.

However while I only have the 90amp Bosch alternator, it just wasnt enough to support driving at night with the A/C on (3 fans running). Too much of a load at idle.

Now I know I could have gone with a higher amp GE alternator, but I just didnt want to spend more money.

When I first discovered my 928 would creep up in temp, while sitting still. I decided to make it right.....

I COMPLETELY flushed the system, removed the radiator flushed it and even cleaned the fins, I even ordered a new thermostat from the local autoparts store (I believe this was the culprit). I even got both of the Orings for the thermostat as well.

After performing this task, the car acted a little better, but not how I thought it really should.

So, I went electric. (Everyone in my thread said my fan clutch was bad anyway)

Well after the temp would still creep up more then I liked (just below the second mark) with the A/C on, and the charging system getting a workout, I decided to make the car back to stock.

I spent the 20 dollars on clutch oil and followed Landseers thread about how to refill with oil. VERY EASY procedure. It took BOTH bottles. I was amazed to say the least. Now here is where it gets interesting. I thought to myself, "What if it was the new thermostat? I didnt get one from our vendors, just a local autoparts store".

So I ordered a nice Wahler Thermostat from one of our vendors.

Conclusion........

This car can now sit in 102 degree Humid New Orleans heat with the A/C on and wont go above midway.


My thoughts are that the electric fan conversion would have kept the temps down with the CORRECT thermostat, but I still would be taxing the charging system. So, the repaired clutch and Wahler thermostat made my car normal again.

I'm not saying anyone elses car wont work, I am just sharing my experiences. Try the fans, they do work well. I just didnt care for how much pull they had on the Alternator.

I will say, buy a decent name thermostat from a reputable vendor. Dont go cheap like I did. LOL.

Anyway, just wanted to share my experience with my 928 family.

Mrmerlin

thanks for posting this info Joey, glad your runnin cool.....Bro.

jcg928s

Thank you MR. Merlin, you were one of the gurus that had given me some direction while I was troubleshooting.

Mrmerlin

Keep Em Flying!!!!

Alan

Glad you are now happy with it - however there is a potential issue here...

You don't really know how accuurate the sender & guage in the pod is so before getting into a lot of work it would be nice to know if you have a real problem with the cooling system or merely an inaccurate sensor...

I'd want to have an independant readout of coolant temp before spending too much time & money to fix a problem that might not be as real as it seems. This could be as simple as testing the external radiator temperature (IR or otherwise) to be sure where you stand before diving in.

Not saying you didn't have an issue here - but in general cooler is not better unless you were too hot...

Lowering the engine temperature too much below the target is a problem for engine efficiency.

Alan

Landseer

I've got 5 gauges on 5 cars. They all read the same when the fan is filled, coolant level is right, thermo seal is intact and radiator is clear, and heater valve is working, ..but they seem very sensitive to slight changes in condition of the cooling system.

I think a lot of the gauge inaccuracy talk we've heard about isn't really the gauge.

It would be interesting to run a true wet calibration check from car to car.

Infrared measurement I've used seems less accurate due to varying surface conditions

Alan

I agree its not a common problem... but since this can be a huge amount of work and expense - makes sense to be sure what you are chasing...

Alan

jcg928s

Well I did measure the temps with an IR gun at the coolent outlet of the motor and the coolant inlet. This was measured on the rubber coolant hose, approx. 2 inches from the hose.

Electric fans and cheap thermostat after sitting for 15 minutes
Outlet 195F to 200F and inlet 185F to 195F

Pulley fan and Wahler Thermostat after sitting for 15 minutes
Outlet 170F to 175F and Inlet 160F to 165F

I know the IR temp guns are inaccurate, but it was all I had.

I compared that with my temp gauge and I was satisfied.

Bill Ball

The radiator should drop the coolant temp a lot more than the 10 degrees you seem to be reporting, at least with the fan(s) running and temp above the T-stat operating point. Shoot the IR gun at the radiator inlet and outlet.

jwillman

I finished my Mystque electric fan conversion this week. My belt driven fan would not hold the new silicon fluid (what a mess) so i went with the dual electrics. I used a hayden dual fan controller from Oriellys that turns on one fan at set temp and then the second at +10F higher. I am seeing volatages at the battery 9 volt meter connnected to battery and read from cabin while running) below battery voltage at idle (AC on, blower hi, Aux elect fan on, bothe radiator fans on) but come back up to ~13V at 1500RPM and 13.4 at 2000 rpm.

I had previously replaced my thermostadt with a 75C unit from Pelican Parts. Don't remember the brand but hope it was a good one! Is there a difference in how opening travel?

I am seeing similar results temp wise from a radiator inlet to outlet using a IR temp gun. What should the differential be?

dcrasta

TL;DR - to sum it up..

The Stock system when working correctly works ?

jcg928s

Thanks Bill, I will try that.

Jim, that voltage looks good! you are picking up the voltage at a higher RPM. It looks like the fan setup and thermostat are working great for you!

dcrasta, It looks like the stock setup is working properly.

worf928

Did anyone ever suggest that the problem might be a migrating impeller on the water pump?

Tony

Don't trust the gauge in the car...

AC on...stop and go...a bit of boost...and about 113'f in Vegas.



Tap the sender right on the water crossover. Best couple of bucks you will spend for accurate temp reading on your motor...especially in hot climates.

jwillman

That brings up another question. What are the symptoms, if any, of a weak / failing water pump assuming no leaking? What about poor radiator effiency?

Driving my car this weekend with OAT at ~100F and AC on with my newly installed dual fans the temp guage neared the 2nd white line while at speed but actually seemed to drop at lower speeds / RPM's.