Hi everyone, I have a 2006 with the 5.4 I installed the FAL-270. The fans keep the engine cool and my A/C has gotten slightly colder. Here's my concern. At night with my headlights I notice my lights flickering when the A/C (and the fans) come on. I bumped my idle to 800 and made no difference. My truck came stock with 130amp alternator which normaly puts out 14.1 volts. I did a volt/amp test with the A/C, fans on. 59 amp draw and 13.7 volts. Fans alone 38amp and 13.9volt now thats with total load including computer, ignition, fuel pump, etc. That is alot of juice I know these truck use alot of power but damn. Anyone else notice there lights flickering? Is this reason for concern? I'm real close to putting the stock fan back on ? Comments......

 

no, but mine bogs down for a second

 

Yeah mine bogs down for a second too. Your headlights and dashlight don't flicker ? and you have under drives ? Nobody else has any flickering ?

 

I dont think it would be any big deal running at 13.9 volts while everything is on. Theres alot of guys with big stereos that probably drop lower than that.

 

mine bogs for a second also. and im runnin a single fan that pulls 30 amps at start up then drops back to about 20. im switching to dual fans soon. that pull only 11 amps each

 

I have the dual Perma-cool setup on mine, I dont think I have the strength of alternator that you do but I can run A/C at night, headlights, stereo, the usual, and my lights flicker for a sec as well but the truck never ever hints at stalling and the lights never go out, just flicker. My idle rpm is stock which is less than yours, but still no problems. I also have underdrive pulleys. I think when both of mine go off, Perma-cool implies about a 20A draw steady state. My only issue with the U/D pulleys, and it is a small issue at that, is turning sharp from either a very low crawl speed or dead stop. The Power Steering is a little tighter at such low rpms but get up to a little speed and it is fine.

 

You might want to invest the $$ in a "soft start" fan controller. I believe SPAL makes one.

 

X2 ^^^ or, DcControl.

The thing here is, regardless of how 'stiff' your power supply is, remember fans are inductive loads, so transient inrush current is many times higher than operating current. That's why the fuses/breakers are time-delay -otherwise they'd pop instantly.

I would not worry about it, IF you've run nice big fat supply line direct to the battery AND your grounding is equally stout.

Soft-start controllers - even those (at least the SPAL - see their online docs), initially apply max power to overcome inertia & get the fans rotating, then drop to a lower power setting.

 

I have the Flex fans and have not noticed a problem with the headlights. Been running the fans for 3 years now. Make sure everything is well with your charging system and battery.

 

The FAL 270 kit is a sort of 'soft-start' controller. It is not a ON-OFF system.
I haven't noticed a flicker either. I have had miine for a few months only.

 

Hi ,
I upgraded my ground cable on the block to 4 gauge stereo wire and my light flickering stopped. I have twin E-fans setup on my 06 Roush F150 w/ underdrive pulleys. This should solve your problem. Good Luck!
Albert