replace clutch fan with Electric fan

[Aloicious]

I have mine wired and tuned to turn on low at one temp, high at another (along with A/C pressures to command high/low), and a manual override toggle to command high speed whenever I want. I personally wouldn't ever run on ONLY a toggle switch if its a daily driver. but then again I also don't trust the cheap 'between the fins' thermostats either, mine is run through the PCM so it is commanded on/off with the same temps through the main ECT sensor.

 

[///M5]

I have mine wired and tuned to turn on low at one temp, high at another (along with A/C pressures to command high/low), and a manual override toggle to command high speed whenever I want. I personally wouldn't ever run on ONLY a toggle switch if its a daily driver. but then again I also don't trust the cheap 'between the fins' thermostats either, mine is run through the PCM so it is commanded on/off with the same temps through the main ECT sensor.

Your setup sounds sweet, and I'm with you that I don't like the crappy fins sensor either. That's why mine is threaded in the head so it can get a good temp reading. On top of that the controller is adjustable, so I can set when I want it to turn on/off. As far as toggle for the main switch, the price is way too high if you forget to switch it on.

 

[Aloicious]

As far as toggle for the main switch, the price is way too high if you forget to switch it on.

I agree, not to mention, if you're running a toggle only and just turning it on when you start the truck, and off when you stop (which is basically what you'd have to do with a toggle, and if so, why not just hardwire it to the ignition or something), then you're negating virtually all the benefits of an e-fan anyway, so I really never understood the whole running the fans ONLY from a toggle philosophy.

 

[1990GMCSIERRA]

i never forget,,its the same way ive ran it on 3 dif vehicles
its too much of a risk to me to have it wire to a tstat switch and never rly kno if its running or not

 

[Aloicious]

i never forget,,its the same way ive ran it on 3 dif vehicles
its too much of a risk to me to have it wire to a tstat switch and never rly kno if its running or not

no offense intended, but whats the point of even having an e-fan then if its ran all the time? the main benefit of an e-fan is that it doesn't need to run all the time. why not just run a clutch fan then? if it works for you, then thats fine, I'm just failing to see the point of running it like that, even if you never forget to turn it on. I have a toggle wired for mine so I can switch on high whenever I want, but its simply a manual override, like just-in-case. I've never actually had to use it in any real situation, other than for testing purposes or showing the fan to someone.

if you're worried about knowing if its running you could do something simmilar to what I did for that purpose, I have it wired to a 2 color LED in the cab to tell me if its running or not, the LED is green for low speed, red for high. that way I can see when the fan is commanded on, and at what speed, or not. I could see what is being commanded in my logging software, but with the LED, I have it there all the time, even when I'm not logging or tuning.

 

[1990GMCSIERRA]

takin off the clutch fan to take strain off the water pump and engine
nothin hurts for ur efan to be running constantly its not hurting ur engine like a stuck clutch fan
thats why most ppl remove them,,thats like havin an electric water pump and only wanting it to run when u get hot i mean rly

 

[Aloicious]

takin off the clutch fan to take strain off the water pump and engine
nothin hurts for ur efan to be running constantly its not hurting ur engine like a stuck clutch fan
thats why most ppl remove them,,thats like havin an electric water pump and only wanting it to run when u get hot i mean rly

most people remove the clutch fan because of parasitic drag on the system when the clutch is locked up vs the e-fan which is able to cycle on and off as needed, combined with the little quicker warm up times from not having a locked fan running from startup. having the fan run constantly would remove or at least reduce both of those benefits, because there IS still parasitic drag on the system from an e-fan, maybe not quite as much, but it is still present, mostly in additional alternator drag. you're right that running it constantly doesn't hurt, but it does diminish most of the benefits from swapping to an e-fan. the clutch fan doesn't 'hurt' the system either, its just less efficent, in fact a clutch fan flows more, and is more reliable when it fails than an e-fan (i.e. when an e-fan fails, it stops all together, when a clutch fan fails, typically it locks up and runs excessively, which creates more drag but still cools the engine). I've never heard of someone concerned about the fan causing water pump strain, the water pump and clutch fan are run off the belt like all other accessories, there isn't any strain specific to the water pump that isn't inherent in the whole system.

like I said, if it works for you, then thats fine, I'm not trying to change your mind or anything. I'm just trying to explain why I wouldn't run it that way personally to the OP, and I still would never recommend that method to anyone investigating e-fan conversions.

 

[1990GMCSIERRA]

to my undestnadin most ppl, remove them to take strain off the motor ,
tats why i did it,,and because clutches get stuck and run constantly and kill mpgs

 

[Aloicious]

to my undestnadin most ppl, remove them to take strain off the motor ,
tats why i did it,,and because clutches get stuck and run constantly and kill mpgs

that is what parasitic drag is, just motor strain. remember though that the motor still has to work extra for the additional drag from the alternator that an e-fan creates (or any electrical draw for that matter). it'll be less than the drag caused from a clutch fan, but an e-fan doesn't completely remove that strain, it just lessens it a little vs a properly working clutch fan.

efan strain < clutch strain, but still strain nevertheless. which is why its great that e-fans can cycle on and off to control when that strain is present, even after full warm up, and that its only there when needed. but if its being run constantly, then the reduction in motor strain isn't all that it could be.

 

[capricefrk013]

Anybody notice that our trucks have an aux cooling fan relay and there is a plug behind the grille for it?

I pulled up a diagram on alldata that shows it coming from the pcm. Anyone know how it is controlled? Thats the only thing I cant figure out.