thunder550

iTrader: (70)

I see where you are headed with this and understand it.....but....the battery will make up the difference that the alternator can't supply. It just won't do it at 14 volts if the alternator isn't charging. It will do it at 12-12.5.

thunder550

iTrader: (70)

Someone in this thread suggested putting a capacitor inline with the fan harness power lead, seems like it might be a great idea....

https://www.performancetrucks.net/fo....php?p=3395793

One of you guys will have to try it though, I'm getting ready to dump the e-fans and go back to a clutch fan to see if I can fix my overheating problems.

white1

iTrader: (5)

Damn Im suprised no one even mentioned it yet. I would lean to the fans pulling too much current. As an electric motor starts getting weaker/going out, they usually draw more current. have you tried an Amp meter in series with the fans to see what kind of current they are drawing?

I use the BOSH relays in my harnesses, but I doubt thats the problem if you have had more than one type burn up.

Also I highly doubt the fans are causing the cooling problems. Everyone I know of has had as good/better cooling.

Did you get the fans new, or are they used? Have you ever had your radiator rodded out? Im sure you have checked the coolant level, also water pumps dont always **** before they go out, but they usually do. Are you still using Dex cool, or something else? Have you tried swapping thermostats again, maybe the one you have in there is sticking a little. You wouldnt necessarly notice normal driving, but when youre towing in stop and go traffic your engine would heat up quicker. I doubt your fan settings being the problem, as long as they are on they are flowing air through the radiator. Your temps may be higher, but you would notice it all the time not just when towning. I know you have had cooling problems for a while, so Im sure you double checked that both fans are PULLING air form the outside, not pushint it throught the radiator (meaning they are spinning the correct way)

Good luck on figuring it out

04BlackSilverado

iTrader: (6)

I put a shunt(ammeter) on the fans and I got 75Amps with one fan on low, the other off, and them both getting kicked onto high(AC on). This is how they will be on start up, this is normal.

How far does the voltage drop on the fans starting up?
What is the resistance of the windings on the fans? I can measure mine for you or maybe someone can do it before 4pm tomorrow.

white1

iTrader: (5)

But what are HIS drawing? If one of the motors is going out it could be drawing too much current.

BenKey

iTrader: (1)

Personally I think the more the fans kick on and off, the more likely you are at experiencing problems. Being an electronics tech, I know that the longer that equipment stays on uninterruptable power the less likely it is to go down for failed parts. Not only that, but it's a strain on your electrical system when the fans come on.

I leave my fans on a setting that once they reach the temp for coming on, the only way they are going to cut off is me turning the truck off. For me that has been the best all around setting for the Summer time. I have only had mine for about 15k miles though, but no problems yet. I also run the Nelson harness.

Wilde Racing

iTrader: (26)

I've thought about this too, (I've also had overheating problems with a set of LS1 fans).
There are two fan control pins for the 02 ECM (thread link) Once I get my larger rad I'm going to try and wire up a new harness using both pins and setting in the ECM.
Any thoughts??

Thunder550 Didn't your truck come with the smaller rad from the factory? And did you install a oil cooler with the LQ9?

TXsilverado

iTrader: (19)

is there a way to slowly ramp the power given to the fans? i had the flex-a-lite vsc before and it had a "soft turn on" feature. i never noticed any hits to the electrical system. the vsc was a POS though...after i got the nelson harness i started to notice the lights flickerin when they come on. also i dont see the need for the one fan on the ac switch to be on high. i also dont see a need for the fan on the AC to be on while your driving down the road...

thunder550

iTrader: (70)

If you are using the a/c as a trigger the fans will always cycle with the a/c clutch.


Yes, I swapped to a 34" radiator when I did the swap. I didn't start using the oil cooler until the 6.0 went in, and I was having overheating probs with the 5.3 before then as well.

Wilde Racing

iTrader: (26)

The evaporator in the A/C system needs air flow, otherwise the A/C system will create too much head pressure and the A/C will not cool as it should.