I've got ideas to add 8-100W spotlights to my 1992 F-150 4x4.

IMO, that calls for an extra battery.

I saw a kit awhile back from Painless Wiring for adding a second battery. I think it was universal, and easy to install.

Does anyone have any tips for adding a second battery? I guess if I wanted to be a cheap-scape, I could scrounge around the pick n' pulls, and pull a dual battery wiring kit off of a Ford dual-battery diesel truck.

What I'm looking for is a second battery that will charge off of the existing charging system, but only run the accessories that I hook to it.

Thanks for any insight.

Nightrain

 

If you want to do the above, you will have to buy a battery isolator. This will let the alternator charge both batteries, but will not let the accessory load drain the original battery you are using now to start the truck. This also lets you use a special deep cycle battery for the 2nd battery, that is designed to be run way down without causing damage to the battery. A regular car battery will not last if it's completely drained very much.

There are no special wiring kits to buy. Just get the isolator to match your alternator output, and follow the instructions.

 

Wow! I almost forgot about this post...

Sorry for the long delay, Dave.

I just found this page of battery isolators. http://www.ase-supply.com/category_s...FQ0qUAodTgwUfw

So, I need to figure out the amps that my alternator dishes out, get the isolator that matches that, and install it with the new battery, per the instructions.

Does that website look like a good, fair-priced isolator seller? Never heard of an isolator until now...

Thanks!

Nightrain

 

I would look into a higher capacity alternator first. These 8 lights are going to be pulling around 65 amps. Double batteries work great for high current/short duration applications such as winches. For lights that you will be running for long periods of time you will need a higher output alternator to keep up with them.

 

Check this out.

http://www.hellroaring.com/rv.htm

 

You can buy the isolators at www.jcwhitney.com too. Whoever you feel comfortable with.

You may want to start out smaller with fewer lamps to see if that works. Like the other poster said, that is a lot of light and you will need fairly heavy wiring and several relays to pull it off. The larger alternator is a valid point with these many lamps. You won't hurt anything with using the stock alternator, but it may decrease the brightness some. You could get by with the stock alt if you reduced the number of lamps.

 

Thanks again, ya'll!

I forgot to mention that the plans have changed a bit... I'm in the middle of a water pump/timing chain replacement, and when I put it all back together, I want to go with an electric fan.

The 2nd battery will be the biggest deep cycle that I can fit in the area I have in mind. At this time, the only thing the aux. battery will be running is the electric fan, when it runs.

A bigger alternator is an option, and one that I've thought seriously about. I'm going to snoop around the electrical forum and see if I can find some threads on upgrading...

Thanks again, ya'll!

Nightrain

 

Skip the electric fan. Put the OEM unit back on. When you replace the water pump replace the fan clutch with a new thermostatic fan clutch also. The OEM setup with a thermostatic clutch is much better than any electric fan.

 

I thought about that also, Torque1st. Just always been something I've wanted to try.

Nightrain

 

i've always prefered a direct hook up with a flex fan. the amount of power i may loose (not noticible to me since i am using a flex fan) is worth the security of knowing my engine cooking over is not at the mercy of an electric fan or a clutch both of which can fail. i feel the same way about these underdrive pulley's guys talk about, they so "oh man i am gonna add so much power by putting on pullys".... all i can think is darn, i am slowing down my water pump. sometimes you get a power gain but is it really worth the risk?

 

Flex fans are worthless except in a race vehicle. They never did do a good job at anything. Flex fans can fail also. The most reliable and efficient fan setup is a thermostatic clutch fan.

 

... Which is what I went with when I put the 'ol 351 back together.

Thanks for the tip, Torque1st.

Nightrain