Electric Fan

[tbirdfiend281]

anyone scrap the old waterpump spun fan for an eletric one? would it be to the trucks benefit to keep the old fan on there being as it runs all the time, or would i cuase any issues to it if i installed a electric fan (being wired up properly and set on the proper temp of coarse though..)?

 

[IDIeselman]

This has been attempted many times, with the end result being replacement of the original fan, the electric fans can't begin to move the same amount of air as the original.
if your fan is on lock up all the time I would recommend replacing the clutch as it will reduce your fuel mileage,power, and the noise can become irratating after awhile.

 

[tbirdfiend281]

its not locked up i was just looking to free some power up, but i figured they wouldnt be able to push as much air...

 

[Diezel_Cowboy]

anyone scrap the old waterpump spun fan for an eletric one? would it be to the trucks benefit to keep the old fan on there being as it runs all the time, or would i cuase any issues to it if i installed a electric fan (being wired up properly and set on the proper temp of coarse though..)?

In the long run you would gain nothing, energy is neither created (from nothing) or destroyed it simply changes form. In other words your alternator would have to work harder due to the extra current draw from the electric fan. SO there would be no gain unless maybe the fan turned off sometimes and it was cold outside.

 

[tbirdfiend281]

an electric fan is theoretically more efficeint, but for it to pull the same amount of air as that huge high rpm mechanicall fan your correct, i dont think im going to mess with it, im not that worried about it, and they still have it on the newer trucks so im sure if they havent implemented an eletrican fan in a diesel yet, i dont need it

 

[soulpatchfr]

dumb questions:

so how do i tell if/when my fan is kicking in?
what exactly does that viscous clutch do (isn't that what it is?)?
and when does it come on? and why?
what am i listening for?

i R&R'd the entire cooling system last year - i mean EVERYThING (rad, water pump, hoses, clamps,stat, cap) -also added the filter.
OK, not everything. i didn't do the heater core, and i completely forgot about the fan... should i for S&G?

thanks, just trying to learn a little sumpn

 

[budtoh3zo]

U will here it, its a loud wirr. Warden has a way to test it

 

[The Warden]

so how do i tell if/when my fan is kicking in?
what exactly does that viscous clutch do (isn't that what it is?)?
and when does it come on? and why?
what am i listening for?

If it sounds like someone removed the IDI and put a Pratt & Whitney JT-9D in its place, the fan came on Seriously, some people have said that they can't hear it, but on both my truck and my old van, the fan clutch kicking in was VERY apparent...all of a sudden, the engine noise is drowned out by a loud WHOOSH of air coming from the engine compartment that roughly follows engine speed. I'm not quite sure how else to describe it. One way to tell if it's working, though...at least on my truck (and the old van), the fan would actually be engaged when the engine was first started in the morning. If I only let the engine idle for a minute before driving off, I'll hear the fan turning with the engine for the first few minutes of driving...then the fluid in the fan clutch would get dispersed enough that the fan would disengage, and I'd hear the WHOOSH fade away over a period of a couple of seconds. From there, the fan clutch only engages when the air flowing through the radiator heats the hub enough to get the fluid liquid enough to flow to wherever it needs to go to make the fan spin. (don't know the technical terms for the parts )

Some people have said that their fans come on at around 230 degrees on the water temp gauge, but mine typically comes on at about 210 degrees, and almost instantly cools the engine down unless the a/c is going full-bore.

BTW, I don't believe that this is possible on our IDI's, but some fan clutches are serviceable. Some Toyota fan clutches have a fill port and sell fluid to refill the clutches f necessary, and some people have found a way to use the Toyota fan clutch fluid to refill the clutch on a diesel Mercedes. Useless trivia for the evening

 

[The Warden]

Warden has a way to test it

I do?

I know that a test exists...I think Pete (cdnsarguy) on TheDramaStop has it documented. I haven't looked at it, though, and am not sure how to do it...

 

[budtoh3zo]

Oh that might be, for some reason i thought it was u that had it? but ya ur right it is pete

 

[sle2115]

In the long run you would gain nothing, energy is neither created (from nothing) or destroyed it simply changes form. In other words your alternator would have to work harder due to the extra current draw from the electric fan. SO there would be no gain unless maybe the fan turned off sometimes and it was cold outside.

Not exactly so as we are not really creating energy, just using a more effecient method of using the energy. In wheel dyno tests on gassers, it is quite easy to pick up a few ponies as the alternator draw is not as severe as the wind resistance draw at high RPM's. Also, the electric fan will "unload" at speed, so even if it activated, it only has to pull/push a small amount of air as the air is being rammed through it at speed.

The main problem I was told by Argve and then by an electric fan rep is the fact that sense a diesel cools at idle, when an electric fan provides it's best feature of enhanced cooling (fan can spin at up to 4000 RPM even though engine is running 750 or so) and an electric fan has little cooling effect at speed which is where diesels seem to need it the most.

There is a dual 18 inch variable speed fan on the market. I asked the rep if it would cool a diesel, he, without hesitation, said NO!

 

[Diezel_Cowboy]

Not exactly so as we are not really creating energy, just using a more effecient method of using the energy. In wheel dyno tests on gassers, it is quite easy to pick up a few ponies as the alternator draw is not as severe as the wind resistance draw at high RPM's. Also, the electric fan will "unload" at speed, so even if it activated, it only has to pull/push a small amount of air as the air is being rammed through it at speed.

No.........what you are both calling efficient is incorrect. The factory fan is powered by a belt or mechanically. An electric fan is powered by current from the batteries which was produced by the alternator which is also powered by the same belt.
So how effiecient is either.....well in the process for the factory fan there is some slippage that occurs for any belt driven device that makes it less efficient than say a chain drive. So for the factory system this is the only major loss.
For an electric fan we have the same slippage of the belt, heat produced in the production and the transfer of current, then there is a loss through heat created in the transfer of current to the fan, and then another loss of heat generated at the fan motor!
You tell me which is a more efficient means of energy transfer!

You have mistaken cooling efficiency with energy efficiency, if an electric fan could cool a diesel engine it may indeed cool it more efficiently, however, it will take more energy/fuel to do so, and any gain in horse power will altimately take more fuel to create the extra energy. IN other words it isnt worth it!

 

[sle2115]

Well, the efficiency also comes from the fact that the crankshaft if not physically turning the fan. The blades on the fan create drag and hence a loss in horsepower. It is just the same as a blower on a gasser. For a gasser to overcome the horsepower it takes to run the blower, it must in fact become a more effecient producer of power. In other words, no one would be installing a blower that takes 100 HP to drive if the gain was only 100 HP, why bother with all the problems. The fact is, that even though the blower takes 100 HP to drive, it makes more than 100 HP. So, in essence, we have gained effeciency. The same holds true for an electric fan. The alternator needs less energy to produce the current needed to run the fan that it takes to turn those big fan blades. Also, the mechanical fans never coast as do electric fans with air is being shoved through them. The mechanical fan may have less drag at speed, but it never goes totally away.

I guess it is a moot point as to my knowledge there is not a fan that will cool a diesel. I have however, seen the rear wheel horsepower figures on a gasser with a straight oe fan, a flex fan and an electric fan. The biggest HP gain I remember seeing was about 16 HP on a modified 427 drag car that made over 700 rear wheel horsepower.

 

[Diezel_Cowboy]

The biggest HP gain I remember seeing was about 16 HP on a modified 427 drag car that made over 700 rear wheel horsepower.

Exactally.........16HP is not worth it to me. I realize that it may be worth it to someone else.
You know what opinions are like................

 

[sle2115]

Exactally.........16HP is not worth it to me. I realize that it may be worth it to someone else.
You know what opinions are like................

Yeah, I hear that. Although if I could find an affordable fan that would cool it, I would take the 16 HP since on an engine that has 150-180 stock, 16 HP would be huge gain. On our 700 HP gasser, 16 HP was only noticeable on the clock!