mastacox

Ok, so I'm doing a bit of research to confirm/deny a theory of mine, which is the following:

Theory:
A Toyota Truck/4Runner with a 3.0L V-6 and Automatic tranmission will have overheating problems if you try to convert to a 'budget' electric fan (Taurus Fan or FAL FLX-165) and drive up mild to moderate inclines...

Answer the poll truthfully, and we'll see if there is anything to this theory.

ChickenLover

I've had overheating problems with the flx-165 on hills. If I'm running the a/c, I will overheat on the slightest of hills. When not running a/c, the hill has to be much steeper and longer for the engine to overheat. But it will. The rest of my cooling system is in perfect shape. With my a/c off, the outside temp has to be in the upper 90's to cause concern. With the a/c on, I run into problems at about 85*.

mastacox

Thanks ChickenLover. The temperature data is a good idea, since someone who live in the arctic should be fine (dang canadians )

04 Rocko Taco

I've heard not so great things about both the FAL and the taurys fan with the 3.0 I think the taurus fan doesnt fit so well inside the shroud, and I'ver just heard a lot of negative thigns about the FAL fans, I know a lot of guys are having luck with them on thier 3.4's though, I didnt vote in the poll, cause I dont have a 3.0, but I've got a theory that a properly trimmed shroud, and a perma cool fan, (WITH a GOOD controller, with an A/C jumper) should be fine even with the 3.0.

mastacox

I understand that with the proper set-up, any engine can be cooled with an e-fan, I'm most interested to see if people with the automatic have on average an overheating problem when going electric. It seems that the 3.0 with a manual does ok, but I have heard about several people that have had overheating problems with the Taurus fan and an auto. I'm trying to see if there is actually a correlation between autos and the overheating issues when changing to an e-fan.

ChickenLover

I've been wondering if there is a correlation between e-fans, high elevation (thin air), and overheating.

mastacox

Well, I live at 7500 ft and don't overheat. But, with an automatic all bets are off, I have a manual transmission. Also, higher elevations tend to be cooler, which might help make up for the thinner air.

aviator

My bet would be that with the added load of the auto tranny cooler and a/c condenser the rad is only just getting enough air flow to do the job with the stock fan.
With the conversion to e-fan [if you're not set up for two speeds] it just does'nt have the moxie to pull enough air through.
You could try putting one of those small [heavy-duty cooling] fans on the auto tranny cooler. [I think some of the big 3 vehicles have these when you order the heavy towing package].
...or just get a manual next time. haha!
Aviator

mastacox

Looking at some numbers, and assuming ambient temperatures are the same, you would have to push 20% more air at 8000 feet than at sea level to cool the same amount... that difference is about 13% at 5000 feet, and 5% at 1600 feet.

mt_goat

I never realized that, so the thinner air doesn't cool as well? So if you were in outerspace with no air there would be no convection cooling?

mastacox

Absolutely correct, convection cooling can only occur with fluid to flow (vacuum = no air/fluid). The only form of heat transfer in space is radiation (and possibly solid coolant sublimation, but that's another topic ).

The cooling capacity goes down because the air is less dense, so it can't hold as much energy per cubic meter (or whatever volume unit you like). Basically, the air is less dense, so you need to flow more of it to get the same amount of energy pulled away from the radiator.

mt_goat

Well that makes sence, I guess I never thought about it and it was probably too basic for my heat transfer professor to even mention, or else I wasn't paying attention.

Marc P

I have run my taurus fan for over 2 years now with no issues. I have a clean radiator with good coolant, a recent t-stat, and I keep up on all services. I have run it in the So Cal desert in many different conditions. Granted when I am crawling on rocks at slow speeds I usually turn my a/c off.

Now that I said this I will probably overheat on my way home

mt_goat

All right dude! And I know it gets hot in Santee, that and El Cajon are like an arm pit lol. But... do you have an auto tranny?

Marc P

Yes..auto trans, 4.88 gears

mt_goat

Great, do you run the Taurus fan on high or low speed? Also do you have a good shroud fit for it?

Marc P

I have it on low speed, with the stock Taurus shroud. I have a mechanical temp guage with sender installed in the back of the engine where the stock sender was.

I use a Hayden adjustable controller, and used an infared thermometer to set it so it comes on when the top of the radiator hits 185 degrees.

I recently added an led so I know when the fan is running. I am contemplating added a switch for the high speed.

Here is my setup


This is the fan/shroud I have

mt_goat

Ok Brian, I'm calling this theory busted

mastacox

DAMN!

Marc P

I wonder if gear ratio/tire size makes a difference? I have 33x10.5's with 4.88 gears.

I know its a streach, but maybe with a lower gear ratio and bigger tires it makes the engine bog down??