Jump to content

Electric Fans?


jbrim

Recommended Posts

I installed the flexalite 282 fan kit about three months ago. Initially I was pretty impressed with the improved performance and quiet operation. I noticed After a few weeks that every time it would turn on my volt meter would drop from 14 down to 11 or 12. It got so bad that it completely drained my battery. The dealership was kind enough to give me a new battery but now I'm stuck with the same problem of serious drainage every time it kicks on, and I don't think the dealership will contiue with a lifetime replacement program on my battery.

 

Is anyone else experiencing this? Could it be a bad alternator or just not a stong enough one? Any advice would help, Thanks.

Link to comment
Share on other sites

  • Replies 78
  • Created
  • Last Reply

I have just installed my fans. You need a little higher idle speed, maybe? I don't really care for how the fans operate. I don't like on and off operations and would rather it stay on. You can jumper terminals 10 and 11, I believe, together and it will run constantly at 100%. Well, 100% is pretty loud and does pull quite a bit on your electrical system. So, what I plan to do, once I do some testing on the thermostat, is put a jumper there with an inline resistor to have it run constantly, but instead of at 100%, more like 60%. I have a 200amp alteranator, so not too worried about the draw. I'll post my results.

Link to comment
Share on other sites

I know what you're talking about. Mine does it too but, knock on wood, hasn't killed a battery. I've thought about putting a capacitor between the power line and the relay. My thinking is it will provide the extra energy needed to get the fans going.

Link to comment
Share on other sites

I haven't noticed any battery problems with my fans. They kick on and off like they should (most of the time).

 

Another option Ben: If you do away with the VSC controller and wire up hard relays for the fan power, you can get them to do some neat stuff.

 

If you wire the fans in a series with only one BATT+, one -GROUND, and a jumper between the - of FAN1 and the + of FAN2, the fans will run at half speed. ;) Much quieter this way.

 

If you run them with BATT+ and GROUND- to each fan, they run at full speed.

 

If you get creative with a couple of relays, you should be able to use a 3 way switch in the cab to move the fans from a series to a direct connection and have the fans OFF, SLOW, or FAST.

 

Merry Christmas.

Link to comment
Share on other sites

I have not installed my fans yet but is the reason your battery is running down because the fans are staying on after the vehicle turns off **to long?** if that is the case you might have a bad relay that is sticking, this is a common of a relay when they go bad. Automotive rule of thumb is just because it is new does not meen that it is good!! goodluck!!

Link to comment
Share on other sites

i noticed the same thing with ctrow. i suggested a capacitor. i don't have fans, but it's the same concept with car audio or general electronics. that's what a capacitor does--provides burst of electricty without drawing down the main system. i think it would solve a good bit of your problem. i intend on installing one when i get fans. they should come with the fans if they are gonna make the motors draw so much power :sigh:

Link to comment
Share on other sites

  • 2 months later...

I'm bringing this topic back.

 

Two times now in the last 6 weeks, I have gone out in the morning to start the truck and have found my truck completely dead. No door locks, no dim lights, not dash lights, NOTHING.

 

First time, I jumped off the truck let it run for 5 minutes or so, then killed it. Even after letting the alternator charge it for 5 minutes, it showed no signs of power. I jumped it again, and drove it for 30 minutes. Then it showed some weak batt power. It lasted until yesterday. Then I found the same issue - completely dead. I suspect the Flex fans VSC controller is the cause. I'm going to get the battery replaced under warranty, then look into my batt power drainage issue more. Ever since the first time it died, it hasn't had the same hot charge and often runs under 13 volts, when it used to run over 14.

 

I will probably rethink the Flex-a-lite VSC for controlling my fans. May let the PCM do the control using 40 amp relays. Probably replace the batt with a deep cycle version too.

Link to comment
Share on other sites

My last two trucks my battery and alternator died at a fairly early age. I know for a fact that the under sized pulleys had something to do with it. In my previous two trucks I didn't change the pulleys and never had a problem. I never had the electric fan though and this is the first one with it.

 

Could it be with the undersized pulleys coupled with the amp draw from the fans that it's just causing early failure? My undersized pulleys never brought the readings up to what it was before the change and I changed out alternator pulley also. Related?

Link to comment
Share on other sites

here's how i did mine, the truck pcm only has support for one pin, unlike the camaros which have two, i believe this hasn't changed and edit can't activate that second pin,

here's the drawing if any of you wanted to hook your fans up to the pcm. be aware, that both fans do come on at one time and there is a slight fall in voltage reading, for about 1sec, when they kick on. it is nice having the pcm control the fans based on engine/coolant temp and not that temp probe in the radiator. I've installed a few fans and i've seen two vsc's go bad.

http://www.ls1truck.com/howto/pcmfanwiring...ing_frames.html

 

later,

 

allen

Link to comment
Share on other sites

Ben, I don't think its really the pulley fighting the alternator and the fans drawing too much voltage. My fans sren't on ver much during normal driving. They do come on when I'm at slow speeds or stopped. They aren't on constantly, just cycle on and off. I think the VSC is the problem. Even with all its cool features, I still don't trust it. The fans shut off and aren't running when I leave the truck, so I think that it may occasionally get stuck in a certain mode and cause a voltage leak. Its totally apparent that something has been left on and has drained the battery. The accessories have that 20 minute auto shutoff, so that can't be the issue.

 

Allen, I've been thinking of a better way to wire the fans. I plan on using a multiple relay setup where the fans are on in a series when the PCM trips the switch. Then either I have control, or maybe the A/C feed controls a secondary switch that moves the fans from being wired in a series to wired in parrallel. This would allow them to run at half speed normally, then full speed when the AC is on or I flip the switch.

 

I'll just add this to my growing lost of to-do items.

Link to comment
Share on other sites

I haven't experienced any battery drain issues so far...

I currently have this setup: VSC controlling fans, underdrive crank pulley (-25%), overdrive alternator pulley (+32%), 145A alternator, idle speed 600rpms.

I agree with Allen on the temperature probe... don't like the lag time in the cooling control. I plan to tap into that PCM fan wire at some point. That provides a ground signal to activate a relay, correct?

Here's what I'm thinking about using the PCM wire... The VSC has 2 taps for the A/C relay, one positive and one negative. The A/C is currently on the positive tap. So maybe you can wire the PCM negative signal to the negative A/C terminal on the VSC and get the PCM to turn the fans on at 60% power. This takes advantage of the built-in slow speed in the VSC. I would leave the temp probe hooked up and in the radiator, so if it gets hotter, the probe would cause the fans to ramp up to 100%.

I have tested the wiring scheme, and it works if you just put a ground to that pin on the VSC. I also checked to make sure activating both A/C pins won't defeat the fans - they stay on with both A/C relay pins activated. So if the PCM signal is just a ground, this should work fine.

:)

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.


×
×
  • Create New...