Has anyone added an additional eletric cooling fan

gscm75 · Dec 1, 2003

I want to add an additional eletric fan to my Av. I plan to leave the existing clutch fan on and only have the eletric come on when additional cooling is needed. Thanks

geo31106 · Jul 6, 2007

I wan't to do the same thing. I'have been having a problem with mine, the A/C compressor started to make noise because the pressure is to high. They told me that i need to buy a ney fan clutch. Where I live is desert so the temps are aver 115 degrees. Does any one have an idea how can I fix this problem, or if there are any auxilaiary fans for the AV.

DougD · Jul 6, 2007

Any decent universal electric fan will suit both of your desires.

FlaBouy · Jul 7, 2007

What year is your Av? That will tell us the best means to control the fans. Some had had issues with adding aftermarket fans and burning up control relays... I run around in 100-105* Florida sunshine with electric fans and Douggie has my stock fan. Coupled with the 160* thermo I usually see 180-190* water temps.....

and I would think the addition of a fan at the A/C condensor would help other known issues also.... :wave:

dhpro · Jul 11, 2007

U can use OEM 2005 e-fans and buy the harness from Nelson or someone else. I never even considered keeping the clutch fan too, but wonder if there's enuf clearance for both? Looks like it but can't be sure...the 05 fans fit over a 34" rad I think, but u can buy LS1 fans that'll fit 28" too I believe. I think I paid $300 with the harness. R/

FlaBouy · Jul 12, 2007

dhpro said:
U can use OEM 2005 e-fans and buy the harness from Nelson or someone else. I never even considered keeping the clutch fan too, but wonder if there's enuf clearance for both? Looks like it but can't be sure...the 05 fans fit over a 34" rad I think, but u can buy LS1 fans that'll fit 28" too I believe. I think I paid $300 with the harness. R/

I run the 28" LS1 fans with a nelson harness.... do not try and run the 34" fans on a Nelson harness... it will burn up the relays.... If you buy the 34" fans and need a harness, PM me or BigBlackAv.... we have a part number for the GM fan harness out of the OEM 2005 ups.... it is a pretty easy intsall...

Good Luck

dhpro · Jul 13, 2007

I haven't had any probs yet...Nelson says they work fine...can u give me more info? R/

FlaBouy · Jul 13, 2007

dhpro said:
I haven't had any probs yet...Nelson says they work fine...can u give me more info? R/

From Allen's site...LS1truck....

http://forum.ls1truck.com/index.php?showtopic=6770

http://forum.ls1truck.com/index.php?showtopic=10629

Several more but I am too lazy to go look.... in Post 29 of the first thread I wrote:

"The problem as I see it in this issue is the use of the larger 05 Fans with the nelson harness.

With those fans you see the following:

Both Fans on High Start up: 87A
FLA (Running Amp): 38A

Both Fans Low Start up: 29A
FLA (Running Amp): 9A

One Fan on Hi Start up: 55A
FLA (Running Amp): 20A

The smaller LS1 style fans like I have that fit the 27" radiator work fine with the harness. The harness is rated at 30A with the smaller fans...... I have a couple harness designs for the larger fans and we are seeing the need to thermally protect the harness in excess of 40A with the large fanset..... The isues with Pin 42 and Pin 33 are almost a mute point in most cases since there are several means to trigger the fanset with a combination of rocker/toggle switches, thermal switches driving off ECT, or just using the stock triggers that GM has programmed into the PCM.... Nice find on the 05 harness part number though... We have just purchased one to reverse engineer so our truck club members without electrical wiring experience can buy an "off the shelf" alternative to wiring ther own....."

At that point I drew up a harness For BBA (who was having the prob) and we found a link to the 2005 harness, so he bought one and installed it. His burnt relay issues went away...