Topic: questions on '05 efan conversion

[axehead]

I have tried to read all of the posts on 05 e fan conversion, and I think that I understand it all. I just want to run it by you all and make sure I'm not missing anything before I hit the "GO" button.

shopping list

05 fans
Nelson harness
have PCM programmed

am I missing anything? It reads pretty easy, but I might be missing something. If I am, please let me know.

thanks, axehead

[oHIobellboy]

I have tried to read all of the posts on 05 e fan conversion, and I think that I understand it all. I just want to run it by you all and make sure I'm not missing anything before I hit the "GO" button.

shopping list

05 fans
Nelson harness
have PCM programmed

am I missing anything? It reads pretty easy, but I might be missing something. If I am, please let me know.

thanks, axehead

If I had to do it all over again, I would go with the Flex-a-Lite set up for the harness and controller. It's cheaper in the long run and you can adjust your fans however your want to. The other advantage is with the variable speed controller the fans come on slow and get up to speed without drawing a big demand from your alternator.

[axehead]

I started out looking at the aftermarket set up, but then found the 05 install. at first glance, the A-Market looks ok, but not as good as the OEM set up. looks are one reason for wanting to go with the 05 install. finding the right parts, and ease of repair, looks, and function are all reasons for the oem install. it worries me that after you have done the 05 fans, you would go with the aftermarket instead of the 05 fans. it really makes me think that I am missing something big. what are the troubles with the 05 fan set up?

axehead

[MyBigToy]

The main problem with the OEM e-fan setup is that the fans pull a large amperage draw when they start up. This causes flickering and dimming of the lights and other accessories and is hard on the whole electrical system. I believe that OBB was indicating he would purchase the Flex-A-Lite harness and VSC controller instead of the Nelson harness and having the pcm programmed.

The VSC starts the fans off at a low speed and ramps up gradually to full speed so you don't get the large amperage draw at startup. It's much easier on the alternator and the rest of the electrical system. You control the temperature set point by adjusting a screw on the VSC to get the "fan on" temperature exactly where you want it. IIRC, the temperature probe goes into the upper left-hand corner of the radiator. I've had my FAL setup in place for about 6 years and about 45k miles now and the only issue I've had was a bad bearing in one of the motors. My "WWW" research revealed that FAL had a bad batch of motors about the time that I purchased my set.

[oHIobellboy]

The main problem with the OEM e-fan setup is that the fans pull a large amperage draw when they start up. This causes flickering and dimming of the lights and other accessories and is hard on the whole electrical system. I believe that OBB was indicating he would purchase the Flex-A-Lite harness and VSC controller instead of the Nelson harness and having the pcm programmed.

The VSC starts the fans off at a low speed and ramps up gradually to full speed so you don't get the large amperage draw at startup. It's much easier on the alternator and the rest of the electrical system. You control the temperature set point by adjusting a screw on the VSC to get the "fan on" temperature exactly where you want it. IIRC, the temperature probe goes into the upper left-hand corner of the radiator. I've had my FAL setup in place for about 6 years and about 45k miles now and the only issue I've had was a bad bearing in one of the motors. My "WWW" research revealed that FAL had a bad batch of motors about the time that I purchased my set.

That's exactly what I meant. Thanks MBT.

I use a Predator for programming and had a custom tune written to control the fans. I cannot change those settings to make any adjustment for the fans. The programmer can change the tune and we email it back and forth but that can take time trying to figure out exactly when I want them to come on.

[Fowlhunter]

I currently have an 02 with the 05 efan mod.  I love the mod but the only down side to this is the amperage draw when they start up, I no longer have the flickering of the headlight but I still see the volt gauge jump when the fans come on.  I replaced the cheap Walmart battery with a Diehard Platinum (AGM) and the headlight flickering has gone away!  I would suggest you go with a larger amp alternator, I think I went with a 180amp but I would have to look to be sure or look at the old threads, I'm sure it was posted there.  Nelson did the tune on the PCM, they tune one to what ever temp you want the fans to come on (I think mine was around 190) and send it to you.  Remove yours, replace with the tuned PCM and return the factory PCM to Nelson.  I love the fact that I can be stopped at a stop light and the Av will continue to blow cold air!!!!  It also doesn't hurt to loose the damn clutch fan from the front of the motor and free up a few HP!!!  Good luck and keep us posted! 

Almost forgot, if you go with a larger amp alternator you will need a longer belt.  This is also the time to change out the A/C belt!!

[MyBigToy]

Nelson did the tune on the PCM, they tune one to what ever temp you want the fans to come on (I think mine was around 190) and send it to you.  Remove yours, replace with the tuned PCM and return the factory PCM to Nelson. 

You forgot to mention the next step when you use this method - Go get a crank relearn for $90.

[Fowlhunter]

You forgot to mention the next step when you use this method - Go get a crank relearn for $90.

Brother, you are correct.  I did have to have a crank relearn performed.     I knew I was forgetting something.  All in all I am very pleased with the 05 efan mod!!

[axehead]

first, I would like to say thanks for all of the input. I wanted someone else to look at what I was seeing, and you guys did! I read as much as i could, and then read more. I thought I had all the steps in line, and was ready to go. after reading more on this install from others sources, and from your input, I ordered a FAL 282 kit today. I still like the OEM look better, but I DID miss a few things in that install. I did not catch the alt. upgrade, or at least thought it wasn't too big of a deal. Cost for the FAL kit shipped was $478 with discount. that's cheaper than the oem conversion. I just hope I am satisfied with it.ha ha. I need to have the cooling ability when the Av is stopped, and I'm sure this will do everything I want it to do. and as soon as it shows up, I will tackle the job. thanks again for the help!

axehead

[oHIobellboy]

Don't forget to take lots of pix 

[Main One]

After learning of the troubles Ski Edition has had blowing fuses with his FAL setup I'm more than pleased with the 05 OEM setup.  Yes, I get some light flickering, but that is better than continually blowing fuses.

You don't have to get the computer reprogrammed to do this mod with the OEM fans, at least not when I did mine.  At the time Nelson sold harness that either used the computer to turn on the fans, or a probe to do it like in the FAL setup.  Since I do my own custom tuning, the choice for me was easy.

I did upgrade my alternator, but if you really needed to do it with the OEM fans, you will need to do it as well with the FAL.  Both sets of fans will draw a good deal of current, and yes, the startup current is higher for the OEM fans than the FAL, but since that is of such short duration, it isn't an alternator-driving requirement.

[Ski Edition]

After learning of the troubles Ski Edition has had blowing fuses with his FAL setup I'm more than pleased with the 05 OEM setup.  Yes, I get some light flickering, but that is better than continually blowing fuses.

You don't have to get the computer reprogrammed to do this mod with the OEM fans, at least not when I did mine.  At the time Nelson sold harness that either used the computer to turn on the fans, or a probe to do it like in the FAL setup.  Since I do my own custom tuning, the choice for me was easy.

I did upgrade my alternator, but if you really needed to do it with the OEM fans, you will need to do it as well with the FAL.  Both sets of fans will draw a good deal of current, and yes, the startup current is higher for the OEM fans than the FAL, but since that is of such short duration, it isn't an alternator-driving requirement.

I did have a problem with the FAL setup, but that has been rectified.  When I started blowing the fuses, I contacted FAL and they sent me 2 new motors to start off the troubleshooting process.  I installed the new motors, but continued to blow fuses.  Another call to FAL and a total rewiring of the fans and controller, I now have it fixed.  I had the controller set too high and when the fans came on, they were coming on at 100% instead of 60%.  I've driven a couple thousand miles since to include a trip to Gatlinburg towing the camper up and down the mountains and it works like a charm.  No more blown fuses.   

[Fowlhunter]

My bad, I actually went with a 145amp alt.  Just wanted to clear it up, I said in an earlier post that I went with a 180amp but that was wrong.   

[Main One]

Regarding alternators and running efans, I figured something out this summer of interest - at least to me!

I put in the 145A alternator when I did my efans, but later installed pulleys to slow down my accessories - i.e. put less drag on the engine, particularly at high rpm.  I played around with and without putting the larger pulley on the alternator, which would slow it down, and contemplated going back to the stock alternator.  It's been I believe a couple of years now, but I'm pretty sure than I'm running the bigger alternator with the slower running pulley.  Alternators usually do not put out their rated amperage at idle running speeds, and with the slower running pulley, my alternator is putting out even less at idle.

Via my HPTuners tune, I had pushed up my idle speed with the AC on and at higher coolant temps to over 900 rpm, but at some point had brought it back down to 800 rpm.  While logging engine data via HPTuners software one hot evening, I came to a 2-lane bridge that was down to 1 lane due to construction, with a temporary stop-light preventing head-on collisions on the single traffic lane.  As I sat several minutes waiting for the light to turn green, after about an hour of running primarily at highway speeds with the AC on, the coolant temp soon was triggering both fans to be running at high speed.  I noted the voltage gauge on the instrument panel was definitely reflecting the load of the fans, lights, AC fan, and stereo loads on the alternator.  Since there was no traffic coming, I also switched on the high-beams to up the load.  (I don't have the all-4 on high mod, but do have 100W KC driving lights that come on with the highbeams.)

When I was able to review on the laptop at home the data I had recorded via HPTuners, I noted that when the ignition voltage hit if I recall correctly 12.0 volts, the rpms began to climb above the programmed idle speed.

My conclusion to this is that if your alternator cannot keep up with the electrical loads at idle - when it is not putting out its rated current output - your idle speed will creep up.  Mine only went up by about 50 rpm, but it was something that I thought I had detected earlier, and with the data was able to see exactly what it was and what it went to, as well as when it started to climb.

My point here is this - it doesn't seem to be as strong a need for upgrading an alternator as I had once thought, since the ECM is smart enough on its own to push up the idle speed if it needs to.  Obviously there are likely limits to how far it would push up the idle, but unless your alternator is much less than needed to support your electrical loads at idle, the ECM should be able to do some compensating to keep you from draining your battery while idling away.

[Fowlhunter]

Great info and good to know, Thanks Greg!!!!   

[OH3_Z71]

I've read through this and some of the other efan threads, I'd just like to clear up some questions... I'd like to do the 05+ conversion myself and I've found some fans for a pretty good price, my question is, what is needed for the 05+ conversion? I seen OBB stated he'd go with the FAL VSC and harness, anyone have part numbers or link to these? I'm guessing there is no pigtail from the factory harness to just straight up connect the fans and just be done. So most likely I'll go with the FAL harness and all, will this be basically plug and play? No PCM programming? I'm assuming no since I'd run a VSC.

Thanks guys, sorry to whore or hi-jack the thread.

[oHIobellboy]

I've read through this and some of the other efan threads, I'd just like to clear up some questions... I'd like to do the 05+ conversion myself and I've found some fans for a pretty good price, my question is, what is needed for the 05+ conversion? I seen OBB stated he'd go with the FAL VSC and harness, anyone have part numbers or link to these? I'm guessing there is no pigtail from the factory harness to just straight up connect the fans and just be done. So most likely I'll go with the FAL harness and all, will this be basically plug and play? No PCM programming? I'm assuming no since I'd run a VSC.

Thanks guys, sorry to whore or hi-jack the thread.

I can answer the question about the pigtail harness. There isn't one. I bought a complete GM harness for the fans and lights (they don't come seperate) and stripped the fan wiring from it. I also had to wire it into the ecm and have a custom tune written for my predator. This leaves me no control over the fans unless I have the tune altered.

I'll let the guys with the  FAL fans answer the rest as I don't want to steer you wrong on anything.

[MyBigToy]

So most likely I'll go with the FAL harness and all, will this be basically plug and play? No PCM programming? I'm assuming no since I'd run a VSC.

Thanks guys, sorry to whore or hi-jack the thread.

As far as the VSC, you'll just have to wire it per the instructions. All that's left is to wire the OEM e-fan motors into the VSC harness. It's not plug-and-play but it's pretty simple and striaghtforward.

[Main One]

Nelson Performance offers a variety of fan harnesses, all at $89 + $10 shipping.  I've been running one for several years.  Some people, including myself, notice momentary headlight dimming when the fans kick in with the AC compressor, but I don't find it to be annoying.  I have had issues with the wire tap that connects the harness into the AC compressor signal, but seem to have corrected that by soldering that connection in place of using the wire tap.

Here's Nelson's fan harness ordering web page:

http://nelsonperformance.com/Fan-Order-Form.htm

[MyBigToy]

Nelson Performance offers a variety of fan harnesses, all at $89 + $10 shipping.  I've been running one for several years.  Some people, including myself, notice momentary headlight dimming when the fans kick in with the AC compressor, but I don't find it to be annoying.  I have had issues with the wire tap that connects the harness into the AC compressor signal, but seem to have corrected that by soldering that connection in place of using the wire tap.

Here's Nelson's fan harness ordering web page:

http://nelsonperformance.com/Fan-Order-Form.htm

I've read of quite a few issues with the Nelson harnesses on PerformanceTrucks . net. Black Bear also makes a harness; I've not seen any negative feedback on his harnesses. If I was going that route, I'd opt for the Black Bear.

[OH3_Z71]

Is there any other option to the Nelson harness? Also where can I get the VSC? Summit?

Thanks for the replys guys!

[oHIobellboy]

Is there any other option to the Nelson harness? Also where can I get the VSC? Summit?

Thanks for the replys guys!

Summit does carry the VSC. I priced them when I did mine and could have saved a whole lot of money going that route. GM harness is over $200, getting the ECM to control the fans is more $ depending on how you get that done. I had a custom tune done for my Predator that cost me $50 plus the initial cost of the Predator.

[OH3_Z71]

alright cool, thanks OBB! found the VSC on summit for just about $100. and about another $100 for the nelson harness.