air dog help

[heavy smoker]

installed a new ad 150,and now truck idles at 23psi and with edge on kill pulls down to 20-21 psi.seems like high pressure for a 15 psi rated pump.checked all return lines no kinks.is this to high if so what is my problem.thanks in advance

 

[cummins724]

I been running 24psi since I started modding my truck, no problems here.

 

[00farmcummins]

if you want to lower it i believe you can get a new spring for the pump this will lower your psi. The spring is just located behind the fitting that came screwd onto the pump. I just put a replacement 150 on my truck because my old one shorted out and my psi is actuallyl higher than it was with the first pump which was 18 and now im sitting around 20-22 but no lower than 18.

 

[JPWCummins]

mine stays on 17 to 18 on idle the lowest i have seen it go is 15

 

[2Tone12V]

Well it sounds like the pump is putting out so much fuel. And the engine demand is so low. The return is probably pumping TONS of fuel. Which of course is how the pump should work. And is causing the pressure to rise a bit I have a bit lighter spring to drop it for you. Probably not much (1-2). I'm going to guess you have a 150?? Which is to big for your app. The 100 is only needed on most any vp44 application. Our gph rating of 150 at free flow doesn't fall near as much as most fuel pumps when at 15 psi. So if your output to the engine is very low. The extra fuel is pumped via the return line back to the tank. And if that line is getting so much fuel through it that the fuel itself has now become a bit of a restriction. The pressure will increase a bit. So this gives you a good excuse to go buy lots of go fast parts now!!:rockwoot: