Need some ideas

WVRigrat05

Wound for sound
Jan 1, 2011
3,081
4
38
36
French Creek, West Virginia
With my Air dog, I do not have to prime main filter. It takes about 7 psi to push through the bypass valve in the CP3 and return to the tank. By chance did you hook up the FASS so that it only runs when the engine is running? Check to see that the FASS is running when you turn the key on.

That's a good possibility too, my raptor was set at like 5 psi. I'm running it at 15,
Reason being is it's a small pump, you should be able to set yours at 8-10.
 

torqued2dmax

Member
Mar 26, 2017
646
1
18
Brookville, PA
A lift pump that has duel filters , you dont need the eng mounted filter head. If you wish to keep it, just buy a new one from a vendor here.This will eliminate any chance of it being a small crack in housing or o rings sucking air in after shutdown then having a small air block till you tap filter head, like you do now. This is a known problem area anyway fix it now.
 

6.6lb7duramax

New member
Apr 10, 2017
13
0
0
I hooked the fass to a ignition fuse so when the key is on that's on I switch the factory filter for a new one and when it was off I made sure the fass was pushing fuel and it was but what i don't understand is when it dosnt start it only happensonce or twice a week is why it dosnt start if the fass is pushing fuel to it it'll only start if I push the primer button and it only takes 5 or 6 pumps and it'll fire right up and be fine
 

ChrisPerry

...........
Apr 4, 2016
209
6
18
Ventura, CA
The fact that you can push the primer down and you have a lift pump puzzles me. After running my lift pump for 2 second you couldn't push the primer down at all.
 

6.6lb7duramax

New member
Apr 10, 2017
13
0
0
It's got me confused too you would think it'll push fuel right to the the cp3 right? But it seems like it's not getting passed there the factory head cause it only takes about 5 pumps till the primer gets hard and will start right up
 

6.6lb7duramax

New member
Apr 10, 2017
13
0
0
I think I'm gunna bypass the factory filter head and see if it still dose it if not I'll just get a new filter head and maybe that will work
 

aashton1206

Member
Sep 3, 2015
172
0
16
Bypass it so it is a sealed system then when you go to start it, leave it in ac for a min to build pressure. Put a rag on the test port then stick a screw driver in the port. You will hear it sputter. When it stops sputtering and just pours diesel out, start her up. You just bled air from the lines


2004 Silverado Cali lb7, Airdog ll 165, fresh sticks at 325k, DSP 5 on v2 by Rick Fletes, 33x12.5 nittos at on 20 inch American Racing wheels, modded factory air box, Profab Intake Horn, Batmo Wheel, Turbo port and polish, Full EGR Removed w/ fed belt, 3.5 inch MBRP Downpipe, Full five inch MBRP Exhaust, 10mm lbz cp3 pump, Dual Yellow Top Optimas, High Output Alternator, Cognito Pittman and idler w/ support kit, Cognito Contol arms, Drilled and Slotted Rotors on all four Corners, Custom Y Bridge.
 

aashton1206

Member
Sep 3, 2015
172
0
16
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2004 Silverado Cali lb7, Airdog ll 165, fresh sticks at 325k, DSP 5 on v2 by Rick Fletes, 33x12.5 nittos at on 20 inch American Racing wheels, modded factory air box, Profab Intake Horn, Batmo Wheel, Turbo port and polish, Full EGR Removed w/ fed belt, 3.5 inch MBRP Downpipe, Full five inch MBRP Exhaust, 10mm lbz cp3 pump, Dual Yellow Top Optimas, High Output Alternator, Cognito Pittman and idler w/ support kit, Cognito Contol arms, Drilled and Slotted Rotors on all four Corners, Custom Y Bridge.