my raptor fuel pump stopped putting pressure out about 3weeks ago. the motor runs fine but no fuel pressure is read from mechanical and electrical gauge. checked voltage and it is good at 8.5 volts without starting it. the motor turns and there is no suction on inlet. so i told airdog about it and they shipped me a new one. i just installed it, and there is no suction. it will not prime. 2 spinning pumps, so what the heck am i doing wrong?

Uh oh... Is it backwards? Try the other side. Seems improbable but they used to be backwards. By the time I got mine they were fixed.Sent from my iPhone using Tapatalk

the first pump was fine for about 7 months, then one day it stopped putting pressure out....was it an internal polarity issue?

Cant say why it would have just stopped working.....but.....you're positive that you have fuel in the tank? Running out of fuel and not knowing it is more common than not. And the new pump wouldn't be spinning backwards either since its not the pump wires which are known to be reversed but the connector on the wire loom going to the pump. So if the old pump spun in the correct direction then the new pump will to.

there is a half tank and i double checked for vaccuum on inlet with inlet line disconnected, there was no vaccuum on both pumps....i know this is ultra rare, thats why i feel like i am doing something wrong ya know.

I didn't mean reversed in that manner.... I meant the input output marked on it are backwardsThe raptor pumps used to be that way anyway. Maybe they got one mixed up againSent from my iPhone using Tapatalk

How did you check the inlet? Did you hook it up to something? Are you connected to the fuel tank module through the OEM quick connect fitting?

check with barb fitting and hose on inlet going into bottle with fuel...also it i elevated the fuel level and it didn't prime .what is the correct way to check?it is the factory quick disconnect for engine mounted pump.

If you have a hose from the inlet into a container with fuel it should be a good way to check and eliminate air leaks and blockage... But seriously is it spinning the wrong way? Sent from my iPhone using Tapatalk

I dont know if there's a "proper" method to prime and really if the pump is working and there is no air leaks in the lines from the tank to the pump then it should self prime. The only possible connector I can think of is the quick connect fitting on top of the fuel tank module. Pureflow will give you this connector to tie into the OEM fuel module but if the module side is damaged upon disconnecting the lines or if the o-ring in the connector is damaged then you will never be able to prime the system since the pump will be sucking air. But if you have a solid sure way to test with other fittings and a hose to a bucket of fuel then I'm not sure what to tell you.

it plugs into the factory harness, but i can rewire it with my new relay harness. i promise it has been functioning for about 6 months..i havent had my truck for 3 weeks, and have taken the pump out and reinstalled it 4 times. give me an idea and i will try it...

--- Update to the previous post...

i just want to make sure i understand this correctly....this gerotor style pump needs fluid to produce vaccuum on inlet and subsequent pressure on outlet. it should not produce vaccuum wheanythingn it is not hooked up to anything.

My thought is a loose connection / failed connector on the top of the tank. Alternatively, the pickup could have come apart. Can you blow air back into the tank (proving not obstructed but not necessarily eliminating a air leak from connection.

it is possible they sent you a bad one? I had that exact same problem with mine after about 2months of using it... however the second one they sent me did work.

i just finished proving that both of my raptor pumps needs more than 8.4 volts to prime itself on my truck. i will not use the factory harness for powering the raptor lift pumps. i wired my harness in and ran 12 volts to it and the fuel came out like it should....it is activated through an acc circuit i am not using and powered through the positive terminal in pdc.

Raptor pump should have its own relay and power supply triggered by the ECM...Raptor should never be wired directly to the ECM...

Raptor pump should have its own relay and power supply triggered by the ECM... Raptor should never be wired directly to the ECM...

i wish pureflo would change the wiring setup for the factory mount 100 gph pump....i am pretty sure its the only pump they offer that plugs into stock harness from ecm.... i will talk to jason the vp and engineer at pureflo, and see if there is anything he can do to change that setup....maybe they will save money giving out warranty pumps.

The relay for my ADII plugs into the oe harness for control. Power is supplied from my alternator. Works very well on mine.

i wish pureflo would change the wiring setup for the factory mount 100 gph pump....i am pretty sure its the only pump they offer that plugs into stock harness from ecm.... i will talk to jason the vp and engineer at pureflo, and see if there is anything he can do to change that setup....maybe they will save money giving out warranty pumps.

Ugh... :banghead: I've never been in favor of directly hooking any pump to the ECM that means of the pump motor is damaged and drawing heavy amps then the ECM takes the hit directly which might of already happened. So if it was me I would give Vulcan Performance a call and talk to Eric and see if he can set you up with a wiring kit that has a relay to it. I'm not sure if such thing exist but its got to be better than direct hooking pumps to the ECM. At least this way the ECM protected from heavy amp draw...

i wish pureflo would change the wiring setup for the factory mount 100 gph pump....i am pretty sure its the only pump they offer that plugs into stock harness from ecm.... i will talk to jason the vp and engineer at pureflo, and see if there is anything he can do to change that setup....maybe they will save money giving out warranty pumps.

I'm not sure what you mean because I purchased my Raptor directly from Pureflow a couple years ago and the wiring harness they sent me was exactly as Mike stated. The ECM only tells the Raptor when to pump but the Raptor gets its power directly from a 12v source. Why would yours be any different?

my raptor is the same, ecm hooks to a relay and the raptor pulls current from battery.

Ugh... :banghead: I've never been in favor of directly hooking any pump to the ECM that means of the pump motor is damaged and drawing heavy amps then the ECM takes the hit directly which might of already happened. So if it was me I would give Vulcan Performance a call and talk to Eric and see if he can set you up with a wiring kit that has a relay to it. I'm not sure if such thing exist but its got to be better than direct hooking pumps to the ECM. At least this way the ECM protected from heavy amp draw...

thank you for offering to talk to eric, but i wired a relay harness and installed it this morning. the truck works great and starts quick and smooth. will still let pureflo know that even though it is in factory engine mounted position, they need to provide the harness in order to save people from waisted timed, and maybe a burned out ecm.