Using Electric cooling fans
 

My son-in-law just purchased an aftermarket kit to replace his belt driven cooling fan with 2 electric ones on his Ford Expedition. He said it would give him 20 add'l HP. I want to economically improve my fuel economy on my 99 Dodge Diesel and was wondering if that same conversion is available and appropriate for my vehicle and if someone has fuel economy increases with the change?

It sure will work. Only problem is that last time I heard, a twin electric fan setup would not pull enough air for towing. You can buy a replacement fan clutch for your stock fan for $600. I just installed an electric fan on my friends engine and it dropped his cruising RPM's down 400 rpms. He was getting like 15 or 16 on the highway and now he's getting ~20mpg. Power is also noticeably increased.

I just installed some electrics on my 96. Since I don't tow, I really don't think I'll have any problems. A "bolt in" kit is not available for our trucks. I made mine out of two fans from late 80's Park Ave's. They're each 18" diameter. It's a tight fit, but with some fabrication they'll go in. I figured that electrics would be fine after running all winter without any fan and I never had any noticeable increase in temp above normal (even in low 60F temps). Will it save fuel?? I can't say. It is quieter.

How did you mount the fans? How are they controlled? Did you use an adjustable temperature gauge to turn them on and off?

This subject has been talked about before and I will say it again, I definately DO NOT recomend putting electric fans in your truck. They just dont have the CFM to pull enough air through your radiator to keep your motor cool. If you tow anything or drive in hot weather you will not be happy. Sure you may save some change in the very long run but then you have to accurately figure the cost of the electric setup verse the gain in MPG. You are probably looking at many years just to get your money back. I know someone that tried this route on a small motor home that wasnt pulling anything but its own weight and it caused nothing but trouble. Not to mention it gets very hot under the hood when the fan isnt blowing the air around. Eventually had to switch back. Plus, just something to think about, how many vehicles designed for towing or HD use come from the factory with electric fans? I cant think of one. Do you think the auto companies are oblivious to the extra HP gains with electric fans in HD vehicles? Just another opinion.

What kind of CFM do our stock fans flows? The one I'm looking at getting flows 2175 CFM and I'm going to mount 2 on there. That equates to 4350 cm. I can get one that flows up to 2350 CFM. Which equates to 4700 cfm of air. That's a lot of air. And if you wire it to stay on all the time, or use an adjustable thermostat to turn them on, I don't see what the problem is. I installed an electric fan on my friends gas engine and his engine struggles to get above 180* in traffic on a hot day. It used to hit 210* with the stock fan. A new thermostat probably helped a little, but not that much. I'm just tired of my fan constantly running.

Voice of experience - if you tow heavy, forget the electric fans. There's a reason Flex-a-Lite doesn't have an "official" kit for our trucks.

I learned this $500+ lesson on my 3500 V-10 which we used to tow a 30' 5th wheel. Let's say the stock fan takes 15 BHP. The twin Flex-a-Lite setup (the largest they made that would fit the V-10) drew 50 amps. Well, 50 amps x 12 volts = 600 watts = 0.8 BHP. As I found out, 0.8 BHP will not move enough air to cool an engine towing a 5th wheel up a 6% grade on a summer day.

Ya pays yore money and ya takes yore chances.... :rolleyes:

Rusty

Electric fans will not cool the truck enough,if you do want to put some on i would use either taurus w/3.8l or a couple from a Mark series car.Just my .02

Why the taurus fan?

I guess it depends on the part of the country you live in and what you do with the truck. Example: My wifes uncle lives in the Pocono's (PA) and uses 1 fan from an eagle talon. He owns an excavating business and repairs all of his equipment. He even does diesel conversions on pickups & vans. All he uses are electrics. NOW if your towing a heavy load or are in the south/southwest maybe they won't work for you. I sure wouldn't count on them to keep the truck cool pulling a fiver out of death valley in the summer up a 7% grade. For me (in the Northeast), I think electrics will work fine. I have every confidence that they'll keep the engine cool enough after seeing how oversized the cooling system is by running without any fan this winter. This post is not intended to flame anyone. What I'm getting at is one size may not fit all. It really depends on what you do with the truck.

All my truck is scheduled for is the 1/4 mile. The heaviest thing it might tow is an 8-10K 3 horse gooseneck. And that gets towed a grand total of 10 miles. The biggest hill we encounter in south texas is an over pass.

Ummmm....yup, but some of us venture into the Hill Country or Davis Mountains with a 13,500 lb 5th wheel in tow. We find out pretty quickly if the fan clutch isn't working!

Rusty

[laugh]

What about switching to a 180* T-stat and using some electric fans? That should help cool things off a bit. I know that a diesel makes power with heat and all that stuff, but I'm wondering if a 180* T-stat and some BHF (big honkin fans) would help keep things under control. My temp gauge staysa needle's width over 190 no matter what. I have full coolant and it's circulating fine and the fan is working. But even on a 60* day, it stays over 190 so the fan stays on the whole time. Talk about noisy and slow. My truck is noisy enough as it is (4" straight piped dumped, no silencer ring, Scotty w/hole). The last thing I need is a noisy fan. I'm curious as to why the fans off a taurus would work vs. an LS1 chevy engine? Those engines produce a lot of heat since they are aluminum (normal temps are 220) and the twin fan setup cools those down. It even cools down the high horsepower guys fine.

I'm surprised I haven't heard anyone mention the Horton fan.:confused:

The Horton isn't really an electric. It is an electromagnetic fan clutch that uses the stock fan.

Mike

And it's like $600.

Last I heard, a stock fan, when fully locked, takes 20HP, and moves 10,000CFM. (PM DTR Member infidel)

I have 3 fans on my truck, but, of course, the truck isn't running yet.

I have 3 16" fans, each moving 1,300CFM through a typical 4 core radiator. I WILL be towing heavy (45' Goosenck @ 6,500Lbs empty), and WILL be racing.

What I wanted was a "snappier" engine, faster cool down, and colder A/C. I guess I'm about to find out how the truck tows with them.

I'll be moving 3,900CFM. Two behind the radiator, and one in front of the A/C condensor.

I'm also running a 180* t-stat, BUT, once the T-stat is open, it depends on how much cooling capacity your truck has. I'm running a lower temp t-stat because of some benefits I have heard rumoured. (better MPG, better response, quieter motor, but on Auto's, hotter tranny temps)

If it's a 160* or 200* t-stat,, if you are overloading (becuase you are producing to much heat, or not removing enough heat) you will overheat.


Merrick

None of the fan maunfacturers recommend REPLACING your stock fan in a heavier duty diesel application. They suggest only SUPPLEMENTING your stock fan. Even if they could pull enuff air, you wouldn't know it if one gave out until your gauges start to shoot up. Then, you might get stopped in time to take action.

Sounds like you've been busy, but then again, I woulda never guessed!!!![laugh] [laugh] [laugh]

MCummins, you brought up a VERY important point about a fan being in front of the A/C condensor. If (whoever) changes out the stock setup for electric then you have to make sure to wire the fans so that they come on with the A/C or you will be looking at a very expensive A/C repair bill.

what about electric draw with so many electric fans and the grid heater and evrything??

If you use a thermostat on the fans, the grid heater and fans will never be on at the same time.

we discuss on the camaro forums occassionally.

in a gas car, if the fans are electronically controlled by a thermostat, then the thermo MUST be set above the temp at which the engine operates at driving speed. (that's where the lower thermostat temp comes into play, the road/air cooling plus the temp at which coolant is allowed to circulate )

IOW, the fan can't run while the car is moving, or "fan wash" will create a wall of non-moving air in front of the radiator (if the car is moving ~45mph, and the fan is pulling at ~45mph, the fan is acutally pushing air backwards, with no flow through the radiator). I've heard it called "Stall out" by some guys, dunno what that refers too.

that's the purpose of the clutch, to let the fan freewheel when road (airflow) speed is higher than fan speed. that's why high load towing = high rpm (fan speed) and low road speed (less air flow) makes our huge fans desirable, because they can prolly flow faster than air slow towing speeds?

i would think in one of our rigs, you need 4 inputs: Thermo control ( for when truck is driving empty) Manual control ( when towing below ~45 ), and AC input, and a timer for when you shut the truck off.

the thermo control is $19 at Advance, put one in kids camaro last week.
got an extra one if anyone wants pics, just a temp bulb put somewhere, and a box that shorts out when get right temp (adjustable by set screw). Put a relay on it, and control whatever.

and 4 fans off an IROC or LT1 should work, long & wide, 2 in front, 2 behind.

i hate running my AC, loud as crap.

Marine and Big Blue, I understand the Horton uses an electromagnetic clutch and costs a bunch of money. Just seems to make more sense than messing with a bunch of electric fans since it will give the results people seem to be looking for. I know the big rigs use a setup like this.

On another note, has anyone looked into the third generation fans? I know the pcm controls the fluid coupling in the fan clutch, if it fits it wouldn't be that hard to make it backwards compatible.

I agree. The Horton is the way to go and is on my list of gear for the truck.

Mike

Does anybody know the part number for the Horton clutch?

Justin

It is the EC450.

Mike

Not true. If and when you use the defrost the compressor is running also. Running the compressor without a fan is no good.

The Cummins ECM (not Dodge) has a fan control circuit to power the Horton or could be used to fire electric I guess.