Aux Lighting Ideas?

[PoppaSpud]

getting ready to replace my factory fogs, since they do little or nothing for me off pavement. and until i replace the factory roof rack (no near-term planms for that), i won't be adding aux lights up there.

i'm thinking of running light channel steel/aluminum or some fab'd metal mounting bar between the two existing light mounting points, then adding 2-4 aux lights there across that span. wiring should be simple enough, and i want to use the existing factory fog switch and existing wiring out through the grille. my budget is under $100 if i can keep it here and not end up with a ghetto-fab result.

my questions/areas of concern:
1. how much draw can i have on that circuit without taxing my battery too much?
2. i want to use very basic round 4" aux lights, metal body preferrably. don't want to drop the cash for PIAAs/Hellas. anyone have any recommendations, or is a walmart/parts store light (with design to change bulbs myself) going to serve the purpose?
3. what watt lights should i look for/do 4" come in? and should i at least get halogen bulbs?
4. has anyone else done a similar mod and can you post a pic of the finished product?

open to ideas.
haven't seen any archived posts on this either.
thanks in advance for the input.

[ August 06, 2003, 09:39 AM: Message edited by: PoppaSpud ]

[Wart Hawg]

I got four 4" off-road round lights from Harbor freight. They cost me about $11.00 each. I hooked them up to a single toggle and they draw about 30amps or so. Not too bad on the battery and as soon as I turn them off it goes back to a normal charge.

*edit* Here's a pic of them mounted to the bumper.
http://www.fullsizejeeps.com/jeeps/files/1963-1983-Wagoneers/P1010012.jpg

[ August 06, 2003, 10:45 PM: Message edited by: Wart Hawg ]

[racer32]

here's how i mounted my new lights on the front poppa-

http://myweb.cableone.net/irace32/bg1.jpg
http://myweb.cableone.net/irace32/bg2.jpg
it cost about $15 worth of steel to build that and a few hours too...

[PoppaSpud]

thanks wart hog.
that's EXACTLY the look and setup i was thinking about... just had questions on the power.
looks nice and didn't cost and arm and a leg, but doesn't look half-arsed either.
nice job.
thanks for the reply with the pic.

racer, nice work there too.
i just don't want to add any more steel to mey rig in the way of a grille guard.

[tgreese]

PoppaSpud, if you use the existing wiring, consider adding a relay in addition to the lights. You can figure how much current the lights draw by their wattage, P (power) = I (current) * V (voltage), so 100w/12v = 8.3A. I'd expect the Jeep driving light circuit to have a fuse that would tell you the maximum that the circuit can support. If you insert a larger fuse, the switch will fail and the wiring could heat up, so you must stay well within the Jeep circuit rating.

Regarding your battery, the alternator rating is the real issue. Except at cranking and idle, the rest of the car should be running off the power produced by the alternator. My WAG, that's 10 or 20 amps. If you have a 60 amp alternator, that means you have about 40 amps left to run the lights. Certainly if you add lights that draw 60 amps and you have a 60 amp alternator, the lights will drain the battery pretty quick.

When I worked with Baja racers, they'd always use a relay because even if they'd use a big, heavy duty switch, it would fail. I'd guess that's because the light's cold filament has a very low resistance, and draws a lot of current at switch-on. Follow up if you need any advice on adding a relay.

best regards :cool: Tim

[ August 07, 2003, 08:47 AM: Message edited by: tgreese ]

[PoppaSpud]

thanks for the recommendation on the relay.
i want to do exactly what wart showed in his post above... and will likely even pick up the same lights from harbor freight.

considering this is one of those mods you don't use every day, you want it to work flawlessly when you really need it.

on wiring the relay i'm sure i could use the advice if you have time. this is one area not covered in the archives (aux lighting, that is). maybe it's not that hard, but i'd rather hear what everybody else has learned so i can save myself the pain... as always another reason to love this board and its members.

again, thanks for the schoolin'.

[tgreese]

Okay, no problem.

I'm assuming that you're going to use lights that will draw a lot more current than your existing driving lights. If so, this requires that you run new, heavier wires to run your lights. You can use the existing switch and wires to power the relay.

A relay has two circuits, the coil and the contact(s). When juice flows through the coil, the contacts are closed, and vice versa. Typically your single-contact relay will have three terminals; one that energizes the coil and an input and an output to the contact. The circuit through the coil is completed through the ground supplied by screwing the case of the relay to the car body. If the relay has a plastic case, you'll have an added connector that's the ground to the coil.

Mount the relay anywhere that's convenient - the inner fender near the starter solenoid would be good. You have to bring the existing driving lights wire to the relay somehow, so look at the layout to see where is most convenient. Connect the existing driving lights wire to the coil of the relay. Add a ground wire if needed. The relay should make an audible click when you turn the switch on and off.

Probably the best place to take power for the lights is from the battery side of the starter solenoid. Use heavy wire (#10) and a ring terminal, then connect to the input for the contact. Important - just like the battery cable, unless you add another fuse (see below) this wire is unfused; if it shorts out, it's gonna burn, so be careful with routing. Ideally this wire should be short, so placement of the relay near the starter solenoid is ideal.

Ok, so the relay coil is now connected to the switch and to a power source. Next you need to consider fusing. Some relays have a fuse inside their case; if so, just use that and be done with it. If not, then you need to add a fuse inline with the contact-to-lights circuit. I used to use a modular thermal circuit breaker - it was about the size of two sugar cubes and could go in the line between the starter solenoid and the relay. An inline fuse holder for glass tubular fuses is probably easiest to find; shops that do car stereo installations would probably have them. Other sources would be MCM Electronics or Parts Express. However you do this, you should keep the length of wire between the starter solenoid and whatever fusing device that you use as short and secure as possible.

Now you need to connect the output of the relay to your lights. Just run the wire or wires so that they don't chafe anywhere and short out. One trick is to put your wire inside some vacuum hose before you route it, then use tie wraps or nylon cable clamps to hold the vacuum hose.

hth :cool: Tim

[ August 07, 2003, 11:38 AM: Message edited by: tgreese ]