Hello everyone, It's been a while since I've been on here.   I've done some minor work to my tracker to make it a little more "practical"  .  I'm especially enjoying the fully bed-lined interior!




As you can see, I have a homemade light bar on there.  I have it wired through a 12v relay and a switch. It works great!

Problem is, with the light bar and headlights running  (No stereo, no heater, no seat warmer) the TOTAL battery draw is ~30A. This means at idle, it's discharging the battery, as well as idling rough    The light bar itself draws about 20A (55watt x4)

It's a "brand new" rebuilt alternator.

Any ideas how to proceed from here?    If I run a second battery w/ isolator (Or different circuit) , will my 55A alternator be strained too much?  I'll never run more then the light bar and headlights, but it would be nice to be able to have the heat on in a blizzard at -50.

Thank guys,

Andrew

You need more Amps from the alternator, a GM conversion, or a hopped
up alternator to supply the increased needs.

Dual batteries won't over tax the alternator, think of the alternator like
a water pump, it can only pump 55 Amps max, so it takes longer to fill
the batteries, get a bigger higher volume pump and fill them faster, at
least that the principal, dual batteries will also give you more time to run
the accessories before you see a drop in voltage

Wild

Do you have AC on there?  If so there is an voltage lead that tells your computer to up the idle speed when the AC is turned on, you might be able to tap into that as a work-around.

I would follow wildgoody's advice though if you want to run big lights.   Bigger alternator and dual batteries.

Thanks guys.

No AC on this one.  The idle is up a little bit already, to help give some pick-up with the larger tires.


Any good links or info on an alternator conversion?   

I'm going to pick up a good deep cycle, and run the lights off that. Run a switchable charging circuit.  That way, it will isolate to JUST the starting battery, then when driving, at speed, flip switch and charge up the deep cycle. I'll put on a battery meter to make sure the deep cycle doesn't run below 20%.

Here's one quick questions:  If I run the lights while driving at speed (no "drain")   will it harm or shorten the lifespan of any charging parts?

Cheers guys,  Thanks alot.

 

Your "brand new" rebuilt alternator is apparently not delivering the power it should - think about it - with the light bar running, you have a 30 amp draw on the battery, if the light bar draws 20A, when you switch the bar off - meaning standard load - there will still be a 10A draw on the battery.

Your alternator should be able to supply the standard loads at idle PLUS recharge the battery (if required) - yours isn't.

The light bar does draw 20A,  but the 30A is from headlights and light bar.   When everything is off, the draw is extremely minimal, and everything seems to be working fine. The battery is charging perfectly to 14.76V.

As long as you don't run your battery completely dead you should be ok.  That is what really kills them.

When everything is off, the draw is extremely minimal

How do I say this ...

When everything is off, there should be NO draw AT ALL - the alternator should have enough output, at idle, to charge the battery - assuming that the battery needs charging - to the tune of 20~30 amps - PLUS supply ALL of the standard electrical loads.

I have an ampere meter fitted to a 1.3 Swift (standard 50A alternator) - and directly after a start, the alternator will charge the battery and deliver the amperage described above, with the engine at idle for the first few minutes, to replace the power used to crank the engine - as the battery charges, the charge current will decline and in under five minutes, the charge current will have dropped to zero - as long as the engine is running, that ampere meter will never indicate a discharge current.

If you have a current draw from the battery, no matter how minimal, at idle - your alternator does not have enough output to supply the electrical load required to run the engine - that might have been acceptable back in the days when cars had dynamos or DC generators, but on alternator equipped car, it's a sign of a problem, and since your light bar is switched off - that is in no way related.