conversion to dual electric fans

[The_Handier_Man1]

From: west coast redneck  (Original Message)
Sent: 1/6/2005 8:46 PM

I have a 440-3 1978.I was considering putting a dual electric fan and going to serpintine belt system. Has anyone done this.Is it worth it .Cost.Thanks



From: mightybooboo
Sent: 1/7/2005 11:34 AM

Never had a problem in any way with the stock system in renewed condition,recored radiator,new water pump and fan clutch,good overflow tank,its a good system,even in hot weather.An electric fan  that runs after engine shutdown would be nice for heatsink I imagine.It does heatsink and overflow a bit after long runs in the desert,letting it run a few minutes at idle before shutdown helps a lot  re: heatsinking.That big ole 440 does run  hot when its been  running hard and long in  hot weather,but the system does deal with it if you dont beat it unmercifully.
BooBoo



From: denison
Sent: 1/7/2005 2:04 PM

     I had thought about electric fans too, until I spent an afternoon crawling up to 10,000 ft in August of 93, in temperatures that were over 90f at 7500 ft, about 75f up at the top.   For the last 45 minutes I had the throttle wide open on the 413, was in first gear, going as slow as 25 mph,  the engine spinning above 3000 rpm.   That reassuring fan roar sounded very sweet.   I decided that the stock system worked so well, that I wasnt going to mess with it.   
    It didnt overheat, max. water temp being about 200f, the engine oil temp showing about 300f, the tranny fluid temp.showing about 275f.  We put 6700 miles on the Winny that summer, and never needed to add water.  The radiator had been out and cleaned in 1991. 
    I have since added an auxillary tranny fluid cooler, which is mounted below the radiator, not in front of it, and hope to add an engine oil cooler next to it, when I see a bargain on one.  This is because I expect to be towing a car behind me in the near future. 
    I have an 87 Chevy conversion van, with a serpentine belt on its 350 v8.  I have had it 4 years, 28k miles, and have had to replace its serpentine belt 3 times!  All of the pulleys are in line, all turn freely, I replaced the idler and tensioner pulleys, and nope; I didn't get it skewed when I mounted it.   At least its very quick and easy to change, since I can lean in above the radiator.



From: mightybooboo
Sent: 1/7/2005 3:52 PM

Agree with what Denison says,Ive never had an overheat condition or had to add coolant while travelling with the stock system functioning as designed,its a winner as is.Cant see changing what works,have plenty other places I could drop money on  it,without fixing what aint broke.YMMV.

BooBoo.



From: west coast redneck
Sent: 1/11/2005 7:34 PM

Thanks Denison & BooBoo.Think your right on the money$.My thought would be expensive & might not work as well as what's there.It may be a little noisy but it's working.Curious though you said you mounted the Tranny rad not infront of the motor rad.My instuructions were to put it infront of the motor rad.Is that not a good thing.?That oil cooler sounds interesting. I do alot of heavy towing up logging roads with a boat.



From: denison
Sent: 1/11/2005 8:30 PM

With my RV the bumper is about 18 inches ahead of the radiator, and almost even with the radiator bottom. I mounted the aux oil cooler more or less behind the bumper, and a foot behind it; supported from one of the angle iron cross members that runs across in front of the lower part of the radiator, and in front of it. So the top of my cooler is about even with the radiators lowest fins, and the bottom of it is just below and in front of a frame cross member, which is itself below the radiator. Therefore, the heated air from the oil cooler is mostly blowing below the radiator, not through it. You might think the bumper is shielding the oil cooler from inrush air, but as its a good 12 inches behind the bumper, it seems to definitely cool the tranny fluid. If I were going to be towing in the mountains, I would mount a small electric fan on the cooler.
With the layout of my grille, I could also have cut a hole in the front sheet metal of the RV, but behind part of the grille that is over the wheel well, not in front of the radiator. The hole would have been about 8 inches square, and not really visible, unless you knew to look for it. This area would allow plenty of air flow too, the air flowing into the wheel well. I might use this area if I install an engine oil cooler later on. I will try to post a picture in the next couple of days.
The only reason to mount the cooler directly in front of the radiator would be if there was no other protected area that would have good air flow.



From: smp5937
Sent: 3/22/2005 12:17 PM

My experience with changing to an electric fan was on a 1985 Chevy Blazer K5 4X4 with a 400 engine. I hauled a 23' Holiday trailer for about 100 miles utilizing that nice electric fan with the automatic thermostatic control, and had more problems with heat than I want to tell about. Before I got 10 miles on the return trip home, I got fed up, pulled the electric unit, replaced it with the original clutch fan, drove home with the nicest swetest temp readings one could hope for!!! Gave the electric system away when I got home. BTW, all the magazines I had read praised teh virtues of replacing the fan with an electric one, gaining horsepower int eh process and on and on...phooey on that I say!!! Give me the original cooling system anyday!!!!!



From: Slantsixness
Sent: 3/22/2005 1:12 PM

simply stated:

Electric fans.... Bad

Mechanical fans.... Good

Having people here on CWM to tell you why.....Priceless.

Electric fan cooling has it's place,  like in the vent above the shower, or behind the stove. Myabe even to cool a remote mounted evaporator or oil cooler. but not for the engine.

Tom



From: RVmec
Sent: 3/24/2005 1:10 PM

I like my electric fans, but I didn't change anything. I just added 2 electric fans on the front of the radaitor and put a switch on the dash to control them. I use them when the temp. starts to creep up such as in traffic or on a slow long climb. Helps a lot.
Parker



From: k0lde1
Sent: 3/26/2005 9:50 AM

I agree that electric fans have a place,
they seem to work really great on small displacement engines that are
attached to "small displacement" cars

While i would never *replace* the engine-driven fam on my RV I am also
someone who plans on *Adding* an electric to aid in cooling.

(i have a 16" fan laying around, what's a bit of wire?)

Robert



From: smp5937
Sent: 3/28/2005 6:32 PM

If you MUST install an electric fan, take a look at the ones from the early 90's Ford Taurus with the big V-6 engines. They are rated at an extremely high CFM, and you can get an electric fan installation kit from your auto parts store, which will include the temp sensor, fuse holder, an adjustable thrermostat, all the wiring, a fan relay and all the stuf you need to attach the stuff to your radiator. The fan can be installed right behind the radiator with the thingamajigs like a transmission cooler is installed with, and I think I remember those being included in the controller kit also, along with the little bumber pads to cushion the fan to the radiator. The entire kit cost me about $50 at our local auto parts store. I will take a look and see if I can find the web link that gives the ratings and info on the fan installation. I had a 400 small block in my Blazer, and the fan was rated and tested to cool that engine. I don't know why I had trouble with it, but I do know that nothing worked like my original clutch fan when it was said and done.



From: smp5937
Sent: 3/28/2005 6:37 PM

Also beware, that some fans are PUSHERS, meaning the fan rotates in such a way that if installed on the front of the radiator, it will PUSH the air through the radiator (thus if installed improperly, it will PUSH air backwards through the radiator, causing a serious OVERheating problem), while some are PULLERS, to do the opposite, pulling the fan through the radiator...obviously the pullers must be installed between the engine and the radiator. Just make sure the direction the fan(s) operate when getting it / them, especially if getting used ones from a wrecking yard. Research is invaluable before shopping a wrecking yard:-)



From: mightybooboo
Sent: 3/29/2005 9:19 AM

"If you MUST install an electric fan, take a look at the ones from the early 90's Ford Taurus with the big V-6 engines. They are rated at an extremely high CFM, and you can get an electric fan installation kit from your auto parts store, which will include the temp sensor, fuse holder, an adjustable thrermostat, all the wiring, a fan relay and all the stuff you need to attach the stuff to your radiator."

Not a bad idea at all.Thinking how my VW runs the fan after shutdown,though it also has a small electric water pump that circulates the water too.Maybe an electric,(in addition to stock fan),setup might be the way to go.
Thinking how bad the 440 'heatsinks' after shutdown,if not idled for a while(esp. in 100+ degree weather) that a 'run-after' fan might be a great idea.
Im wondering,would the coolant thermosiphon thru the system.If so,should be a good setup.
Any thoughts on that?

BooBoo



From: denison
Sent: 3/30/2005 5:52 AM

The coolant will definitely thermosyphon through the system somewhat, if the water flow through the radiator is vertical.



From: smp5937
Sent: 3/31/2005 12:23 PM

"I like my electric fans, but I didn't change anything. I just added 2 electric fans on the front of the radaitor and put a switch on the dash to control them. I use them when the temp. starts to creep up such as in traffic or on a slow long climb. Helps a lot."

I assume that since the fans are located on the FRONT of the radiator, the fans are the PUSHER type? If you installed them, you would know for sure, but I just wanted to jog the minds of those who may not realize all electric fans do not run the same direction.



From: Slantsixness
Sent: 4/1/2005 7:07 AM

I have some generators here at work (just a "little" larger than an rv Generator) anyway, they have 4 16" electric 28V fans. One of the fans has to what looks to be heater hoses (3/4") connected to a pump housing on the back of the fan. It circulates the coolant after the genny engine shuts down. Cool. But the thing would never fit in my winnie, since the fan is almost 12" deep and runs on 28v!

(these generators are about the size of a D18)

So whay dont they make something like that for vehicles?

I still don't like electric fans for engine cooling.

Tom



From: mightybooboo
Sent: 4/1/2005 4:04 PM

"I still don't like electric fans for engine cooling."

They seem  pretty good in the new cars.

BooBoo



From: denison
Sent: 4/2/2005 11:23 AM

If the vehicle cooling system was Designed for an electric fan, I would figure it was fine. I just dont know what the appropriate fan(s) and radiator rating would be for a vehicle gross wt of 13k pounds, towing a car up across the continental divide at 25 mph, wide open throttle in 1st gear.
I imagine the electric fan would have its own maintenance needs too; oiling its bearings, replacing its brushes, or maybe just replacing it entirely each 10 years or so, along with the thermal sensor and its control relay.
My 87 Chevy G20 van has a belt driven fan. I drove it home; and before I used it, I replaced the radiator and both hoses, the serpentine belt, the idler and tensioner pulley bearings, the water pump, radiator fan clutch, and heater hoses. It was running fine before, and I wanted it to stay that way. Normal maintenance @ 200k miles or on an 18 year old vehicle.
Before I tow a car across the rockies, I will be adding an electric fan in front of my tranny oil cooler - which is mounted low so the heated air coming out of it does not blow into the radiator.



From: smp5937
Sent: 4/7/2005 10:20 AM

Denison, I never mentioned the fan on the tranny cooler since we were talking about radiators, but I believe that is one thing that is a great idea!!! A transmission gets warm enough by itself under normal usage, but hills, towing, extra weeight all add up to ABNORMAL heat buildup, and especially with the old radiators being the only tranny oil cooler on a rig!!! A tranny cooler mounted in the right place and utilizing a fan operated with a thermostat to automatically turn teh fan on is a fantastic idea I picked up when I was into 4x4'ing with my Blazer a while back. Some of the reading I did mentioned to place the tranny cooler underneath the rig in a place where the airflow was greatest, and to mount the auto-controlled fan right on the cooler. This location helped remove the heat away from the radiator (probably not an issue on a MH where you can locate it way out in front of the radiator) and also put it where the cooler got the most air flow. A great location on a pickup truck (for example) would be underneath the truck right where the airflow came down between the cab and the bed. I don't know about a motorhome, but I assume that with all the space up front this locating would not be too much an issue, and in addition to the longer lines, more cooling would take place by airflow across the lines and via the cooler itself in addition to the radiator cooling?



From: SeaRaySRV16O
Sent: 4/30/2005 8:54 PM

SMP ... I believe you will want to both keep the length of your tranny cooler lines to a minimum as well as limit the number of right angle 90 degree fittings. Too much line length and too many sharp turns will actually inhibit the fluid flow resulting in poorer cooling rather than better. Big truck aIr brake systems experience a similiar problem when they get too many turns and too much length in the air lines.

Regards,

Robert Donley
Jenison, MI



From: greezmonkey
Sent: 5/1/2005 4:58 PM

I switched my 360 to dual electric fans that I recovered from a honda accord, seems to work great.
danny