I was gonna stay out of this one, but Lead Head's right about the heater core being on a separate loop. The vast majority of traditional engine belt driven fan clutches aren't computer controlled though. Most are the old-fashoned viscous clutches that react to the temperature of the air coming through the radiator. My '08 is the first truck I've ever had that has a computer controlled fan clutch, but it doesn't come on to help warm the engine. Not that I'm saying that there aren't cars and trucks that do it, just that I've never seen one.

140 KW is roughly equal to 190 HP. That is a LOT of power to cool at a standstill! I don't think most trucks could keep an engine cool at a dead stop with that kind of continuous output. The fans are supposed to supplement air coming naturally through the radiator, not replace it!

 

Well LH I see you're dodging the evidence now that efans can keep the truck plenty cool. Your claiming that a mechanical fan can keep the engine cool and an e-fan can't, yet there's plenty of evidence that they do so, while affording better winter characteristics. A properly built fan (aka not some 30$ Tripp-Lite fan) set in tandem (like dual 14 or 16" models) will easily draw 5000-6000CFM. This is while creating much less parasitic load on the engine, giving more power to the wheels rather than the fan. You should like that as much as you're hailing towing 9,000lbs.

As for the heater core reference, if you've messed with computer water cooling you'll know that dumping fluids in a common reservoir tends to make them share heat. This is why in systems running double xeons with Crossfire 5890's or SLI GTX295's, you can't share a reservoir due to temperature concerns. But go on believing that cold coolant and hot coolant have no effect on each other.

 

You keep providing me with loads that barely tax an engine. A mechanical fan can flow 10,000 CFM or more through the radiator. There is no such thing as a free lunch. Which means if that electrical fan could flow as much air as a mechanical fan, it would draw the same equivalent load through the electrical system - through the alternator. So if that electric fan could flow as much air as that "15 HP mechanical fan", that means there would also be 15 HP worth of electrical draw through the alternator with e-fans.

Sorry I don't bother water cooling my Opteron my old x1800, no need too. You can't share a reservoir with those types of system because most liquid cooled computers have all the water blocks in a series. So by the time the water hits the last chip in line, its already burning hot. So if you have two separate loops you can keep overall temperatures lower.

This is untrue in an automotive situation. The heater core and the radiator are in parallel. The radiator has a thermostatically controlled valve at the output from the heads or water pump. This valve is after the heatercore supply line. That valve remains shut until the coolant temp is around 180*F. When that valve is closed, the radiator effectively does not exist. The effect is minimal. You should be more worried about all the uninsulated metal in the cab, or the bare metal engine block being exposed to the cold air then a closed off separated reservoir of cold water effecting the warm coolant in the engine

 

You're not understanding the point. That is unnecessary load and draw. There's no need for 10,000CFM on this engine, the liquid capacity of the radiator simply does not support the surface area. You would be better off putting that power to the wheels, rather than generating it to cool itself to a point that the thermostat clicks off and the fan is still turning anyways.

 

But like I said, old school mechanical only fan clutches did a pretty good job by themselves unlocking the fan once the radiator cooled down to a point, and newer cars with electronically controlled clutches, you can go ahead and grab the fan while its running and it won't try to rip your hands off.

 

Try using the search function. I've posted my reasons before.

I'll NEVER own another truck w/ E fans, they just don't get the job done in "ford tough" situations. The E-Fans can not pull the same CFM the 07+ expedition and 09 F-150 electric clutch fan can. I'd like to see you pulling a trailer at max GCWR in the west, WOT, A/C cranked, Ambient outside air temp at 100*+ with E fans TRYING to cool the engine, I can assure you it will heat up more then the same truck with a clutch driven fan. A good electric clutch fan will work wonders. As mentioned it locks when needed and unlocks when not needed. If e fans were that great equipment and 3/4 ton and up trucks would run them. E fans simply can not move air like a clutch driven fan.

 

But the efans can, living here with temperatures well over 100 with 90%+ humidity I can attest that they work just as well as the mechanical fan on the 150. On the diesels? no not really. Again the radiators on these trucks aren't big enough to just blow air over them. There's just no way for it to get that much surface area.

As for completely unlocking, I'll believe that when someone turns on their truck, lets it idle at cold to mid temp (shouldn't be any coolant flowing seeing as the engine needs to be warmed), and sticks their hand into the fan and the fan should be stopped by their hand. Heck for the safety, use a stick I don't care. Until I see that the BS about the fan being *completely* off (thus no parasitic loss) is false.

 

Do you think ford didn't test the trucks in hot weather towing up grades???? Or Gm didn't......or ANYONE ELSE....and for that matter....why has no one had a problem????


Its the same people usually that complain they still don't make 4.9L's, 460's and 351's because those were so much better than 5.4's or 4.6's.....and the same people that swear they won't buy a new truck without a stick...... Come on people....let the new technology prove or disprove itself based on the TRUCKS PERFORMANCE.....not your opinion

 

Do I hear an Amen to that?


AMEN!

 

YouTube - BMW E39 540i Fan Clutch Test and sprak plug replacement

 

A BMW? No I don't think so. There's a difference between a performance car and our run of the mill trucks. Huge differences in quality and build. I love ford, but I know ford cuts corners on quality parts like every other car builder out, I'm not a member with the blue blinders on. A 10 year old high end 540i is still worth nearly 11grand, no F-150 has that price tag other than lightening and other limited production models.As has been stated most of our trucks don't have computer controlled fan clutches, I know my 04 Expy doesn't. Show me sticking their hand into OUR trucks and not getting it cut off, then I'll believe it.

 

A fan clutch is a fan clutch. My fathers '03 GMC Envoy has an electronically controlled fan clutch and there is not particularly special about that vehicle.

The old mechanical only factory original fan clutch in my grandfathers 87 Dodge behaves the same way as in that video. I'll get a video if you'd like.

 

If you really want to disprove the electric fans.....show us some evidence of electric fans NOT working.....who cares if engine driven fans work....we all know they do......but show us somewhere where someone with an electric fan....any brand....towed something and overheated because they didn't have an engine driven fan....

 

Nice challenge but it ain't gonna happen.

I drove a 2002 Ford Focus completely overloaded across country in July 2002. I hauled *** across Texas, New Mexico, Arizona and scooted across the mountains into SoCal just as fast as that little car would take me and the needle NEVER moved. In 2004, I did it again but coming back to Va. No issues.

I'm sold on E-fans and I'm happy as hell that Ford has finally integrated them in the F-150's. I hope the Expy's get them too.

Tim

 

Here:
Cooling Fan, Flex -vs- Electric - Performance Message Board

Thats just one, and there are many people people out there who reported over heating issues when towing with electric fans.