Brother, can you spare 15 amps? (1 Viewer)

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Eicca

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So I'm wondering if there's a way to test if my rig's electrical system can handle the additional 15 amps that a foglight set will draw...?

I've got an 80 amp alternator in there right now.
 
BTW take a look at my sig line. Everything in there is still using the stock amp. I haven't had any time to actually install PHOTOMAN's 150alt setup.
 
Just don't idle long with everything on. On a recent trip we had to limp a broken truck down an icy mountain - several hours with most stock lights and fans on and idling along very slow. The stock alternator didn't keep up, and when I shut it off, the battery was dead and woudn't start it. The other running truck in our convoy had the same problem.

I've since installed a Hellroaring dual battery setup. It has an LED on the cab switch to indicate if the second battery is charging (ie. has enough voltage from the alt). With high beams and the blower on, that light goes out at low idle. I have photoman's Tundra alternator bracket & a 150A alternator sitting in the shop.
 
Thanks. I'm gathering that it's a fairly common occurance for the alternator to not work as well when the idle is slower?
 
Sounds like alot of us have this problem. I do. I have searched and found that some guys have run 2 gauge wire from the alt. to the battery and bigger grounds to fix this. Sounds like it has worked. Haven't had the chance to try it yet. I just bumped my idle up to about 900 rpm for now. Charges much better.
 
Sounds like alot of us have this problem. I do. I have searched and found that some guys have run 2 gauge wire from the alt. to the battery and bigger grounds to fix this. Sounds like it has worked. Haven't had the chance to try it yet. I just bumped my idle up to about 900 rpm for now. Charges much better.

When I put in the Hellroaring, I put in bigger battery grounds (2 gauge I think) but haven't changed the alternator cable, since I'll be swapping that out soon.

And yea, bumping the RPM even slightly turns that light on again - I've been toying with the idea of hacking into the AC throttle-up circuit to that effect.
 
larger charging wire and better grounds can't hurt, but at idle, the alternator isn't designed to put out max amperage. If you are idling along a lot, you can occasionally rev the motor up to 1,000 or so and shut down non-essential electrical loads, to make sure that the battery is at least getting some juice.

power management is key as well.... don't let the high beams run if you are sitting reading a map (unless you are also driving above idle once in a while). Consider dropping your internal fan down to 2 or 3 instead of 4. Turn off the tunes. Stuff like that can help out when you don't have engine speed to charge your system.
 
So what methods have people used to bump up their idle speed?
 
Can such be done with like an ISC valve adjustment or similar?
 
brick on the gas pedal?

the hand throttle is a lot nicer looking.
 
there is probably also a way to hack the AC idle-up control such that you could bump the idle up to 800* or so w/o turning on the AC. On my diesel you would only have to run power through a little vacuum valve to get the ac idle-up w/o the AC.

not high enough for much power, but better than standard, lower, idle

*I don't know where the gasser motor idles, nor where it idles w/ AC. But it is likely below 1,000
 
It idles when warm at about 600, sometimes lower for some reason. The alternator starts to work better at around 900 in mine.
 

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