I bought a used Airdog II 200gph off a 95 p pump truck and it came in the brown truck today. I am workin on gettin it all on the truck with my custom fuel sump. I gotta get a few more fittings tomorrow and get the pressure adjusted right then I can button it all up. But since I bought it used it had no instructions or anything. It came with the wiring harness with the relay and fuse and all that.

But I've noticed on the newer trucks that have electric pumps that you turn the key on and you can hear the pump come on and prime for a minute then shut off til you start the motor then it kicks on again. I've talked to a few people and they say the computer on the truck tells it to do that and not sure how it would work on my truck. I was just gonna hook the relay up to the battery and then hook the switch or ignition to turn it on to the FSS so that the pump will still run along with the motor when I turn the key off since I have a cooldown timer til it all shuts down. My main question is though will it be bad if I turn the key on and the pump runs the whole time til I start it? instead of just a quick prime and stop or how does that part work? or how would I wire it in to do that? thanks.

I'm puttin too much electrical stuff on this mechanical truck

 

I don't see any problem with it like that. That's how I did it.

The LP will pump way more than the IP uses anyways(hopefully), so really it won't be much different than when the engine is running.

 

I figured it'd be okay but I was wondering if it'd have more of a chance of blowin the front seal or other seals out of the ve or would it just go right through the pump and return even with the motor off? I guess once I put my grid delete back in then it'll be pretty quick starting from when I turn the key on.

 

My pumps on Dmaxes and VP44 CTD (FASS, Airdog, and a Raptor) don't shut off. They come on at key-on and don't shut off till the key turns off.