I have a 78 ford f250 and it has a place for a second battery and i was wondering if someone could tell me how to hook one up.

 

Are you looking to hook it up as an AUX battery for a camper/trailer, or in parallel as a second battery for the starting/truck system?

 

parallel, i have an amp and the battery dies pretty fast when the trucks off and im listening to music.

 

A parallel connection would only need a ground cable added from the secondary battery to the chassis/engine, and a new positve cable run from the drivers side battery on over to the right side positive battery post, or, it could be connected to the battery side of the solenoid..

 

Hayapower is correct....but in my opinion it is much better to also isolate the batteries from each other with an aftermarket voltage regulator. This is placed where the positive cable from second battery would connect to positive side of primary battery.

check http://www.vandwellers.org/isolator/index.html for a great diagram and more info...

It would be worth the 20-30 dollars to purchase an aftermarket voltage regulator to isolate the second battery from the first....then run a deep cycle battery as the secondary power source....and hook up aftermarket items directly to deep cycle (amp and stereo...etc)

Main reason is that this setup will keep primary battery fully charged for essential uses(starting engine...etc) and secondary battery can be run down significantly and still be recharged..

if you hook them up directly in parrallel without regulator...you can run them both down simultaneously and be stuck with two dead batteries...but you can listen twice as long as you do now!!

also consider an aftermarket alternator with higher output if you are running more than the normal amount of accessories.....

 

aftermarket voltage regulator is also called a Battery Isolating switch. (An automatic cut off solenoid type.)

 

That was the reason I asked if it was going to be an AUX battery.. If he needed just some extra reserve, then possibly just a parallel connect.. A heavier draw w/KOEO, or the possibilty of a component being left on, or for long periods of time the system should be protected with a battery issolation switch..

 

Thanks guys your a big help! sick of jumpin my truck