I need some soft start controllers for the fans ive got sitting under my tool box at work....

factory temp sensor is on the intake manifold near the T-Stat

 

OK, you're gonna have to explain to me how a running fan, drawing air in the direction of air flow, reduces air flow?? How is that fan any more of a hinderance to air flow over one that's not running? The incoming air flow is basically blowing that fan in the direction it want's to turn anyways, not much drag on the motor there in my eyes. Clutches...in an electric motor??

 

sorry i meant to say "brushes" not "clutches"

anyways, think of it this way:

lets say your fan is 2200 CFM (Cubic feet per minute) at full power.
16" fan has an area of 200.96 IN^2
2200 CFM has a volume of 1573.63 ft/min imperial calculator
1573.63 ft/min is the equivalent of 17mph calculator

so after 17mph your fan is no longer effective, and will actually be reducing air flow, by trying to spin at its max speed of 17mph. So you're doing 60, the air coming in is slowing down to 43 and you're overheating over torquing your small fan motor, thus burning your brushes.

 

Copy that, and agree with everything you just said, but I think you're trying too hard, LOL! I also have some actual, observed rebuttals to your statements.

After 17mph, fan is no longer effective??? I traveled from Sacramento to St Louis pulling my full, 23' toy hauler in late June of last year (insert your own outside air temp assumptions here) I drove for years with the same assumption as you...the fan makes no difference at speed (from observed operating temps, anything above 35 mph, but whatever...moot) the same thing you said. During this trip, on some long, hot, grades, my water temp (monitored via real temp gauge) would occassionally rise to my personal "no-fan" limit of 225* (and saw 230* couple times). Now, using your theory that the fans are completely ineffective above these lower speeds, you'll now have to explain to me how turning my fans on at 65+ mph, would cool my truck down from 225 and climbing, all the way down to at least 200, if not 195-ish. Every single time! Turn the fans back off, temp starts climbing again.

I would argue two more points...

By the time a particle of air makes it through my grille, my big tranny cooler, the AC thingie, then my two core radiator, I'd say the impact pressure on that fan is minimal at best, maybe even non-existant. (note--this is the [my] reason/theory the fans actually are effective at upper speeds...they still draw additional air across the radiator)

If the airflow through all that was significant enough to drive the fan, it's driving it in the same direction the motor is trying to turn it anyways, thus assisting the fan motor, not over torquing it in any fashion.

I also don't see how a fan spinnning under power in the direction of the airflow would induce more resistance over a static fan. That makes no sense to me at all.

Not trying to argue with ya Pat, I've just observed things as mentioned that rebute what we would have normally thought.

 

my personal experience, towing with a car hauler, and a 4k car (around 6k total) My fan would try and turn on at highway speeds, and when it was coming on and staying on, my truck started getting warmer then "normal" on the dummy gauge. Pulled over turned controller to max heat, continued trip with AC on (in July) and never got above operating temp again.



my setup at the time, was single 16" fan (passenger side) on a single core radiator.

I since have gone to a dual core, dual 16" fans, and a beefy trans cooler. and haven't gotten hot under any circumstance again.

 

Was your a/c wired to the fan? If so your fan was running most of the time anyway. The single core rads suck ***** when you are working your truck.

 

no, never had it wired to AC.

currently have a switch per fan, and a basic temp controller for the primary fan as a system redundancy

 

I had an extra long weekend this past weekend and loaded the quad up and hooked up the travel trailer and went to Caroline Alberta. I saw my temps rise to 228 degrees with both fans running (shown on my Gryphon). If I shut them off it would keep climbing just like Galaxy. Maybe I need to upgrade my rad as well like Gotts mentioned.

 

FWIW I run a 180° thermostat.

 

^^^It would open sooner but would that help much when I am loaded up and making my truck work?

 

Yes, with a 180* thermostat, it opens earlier but does nothing for cooling. It does not aid cooling capability contrary to popular belief. For example...your truck was heating up to 228* because the system did not have the capability to keep it any cooler under whatever conditions you had it under. A cooler thermostat buys you nothing and your truck would run the exact same under those repeated conditions. Don't know why guys continue to want to run a cooler thermostat when this motor is designed, makes the best power, and most efficient at 200 + - 5 (this does not include forced induction motors with tunes calling for cooler thermostats...I'm talkin NA)


I ran another small test on my truck the other day...starting with a normal temp and a heatbindex of 102 outside, I drove around to see what speeds had what effect on temps! At any speed under 20 mph, the water temp (on my real gauge) continued to climb consistently. It took at least 30 mph just to maintain any type of steady temp and 35+ to induce a cooling effect back towards normal. So much for the 17 mph theory.

 

I was looking around for a two row rad for my truck and I found the choices are limited.

The first thing I found out is that you can't have the OEM rad recored to a two row because the plastic tanks can't be expanded to fit.

There is one on eBay but I am not sure of the quality.

Auto Parts Warehouse has one with a 1 year unlimited mileage warranty. Part number P2136 that will fit the 97-04's unless you have a King Ranch then 01-03 or the HD are 00-03. The price looks good (not sure if I can post that) but I need to look into shipping it to Canada.

I still have not pulled the trigger on any controllers yet either. I have one working still and the other will come on with the defrost so I may hold off until the end of summer and towing/camping season so my truck is not out of commision when I need it. That will give me some time for more research but right now the Spal PWM-V3 is a front runner.

 

I went to a good, local radiator shop and asked for a radiator for a '97 F-250 LD...didn't seem to be a problem.

The SPAL is my fav too!

 

I will check into that. Since your truck is an 02 that should work for me as well.

Thanks!

 

Thats a spectra premium rad 2136. I have the same one. They sell them at partsource here in Canada. Don't ask for a rad straight up for your truck or they will sell you the single core replacement. Give them that number p2136. They will get it to you in a couple days.