I just installed a Fass 165gph system on my truck. I previously was running the carter pump on the frame with no issues. Now if I let my truck sit over night it cranks longer before it starts. Also I see no fuel pressure on my gauge until after the engine starts. My fuel pump is wired to the 10 amp fuse in the cab marked ignition. After the truck sits over night I turn on the key and check the fuel neck to see if the pump is pumping and maybe my gauge is wrong but its not until the truck starts. I am lost on this one its not that complicated of a system but this has me stumped.

First off I'm confused why is the fuel pump wired to the ignition fuse in the cab? It should be hooked up to the ECM and a control relay. The relay should be hooked up to battery power typically I hook it up to the PDC +12V stud.

 

During cranking the ECM will command 50% duty cycle which will pulse the power on and off and get the pump to run about 7-12 PSI during cranking. Typically when you turn the key on the first second it will pulse the pump and usually get a pressure spike before you even hit the key to start. 

 

You might want to check with another gauge to verify your gauge is showing correctly. The only reason there would be longer starts and no pressure is a loss of prime. You may be seeing fuel in the filler neck but there could be an air bubble trapped in the rest of the system.

I'm not getting any pressure until it starts, once I start it I get pressure and normal starts every time till it sits over night. The reason I bi passed the ecm is the carter glitched a couple times on me so I wanted to bi pass the ecm. Fass recommended I do so. I still am using the relay just the 10 amp ignition for a trigger wire.

When it sits over night the pump is whisper quiet and not returning any fuel to the filler neck. Once I start it sounds gargley like it has air in it, I drove it on a 2 hour run with my camper and it still sounded like that when I got there.

First off with a mechanical gauge you won’t see pressure after you shut it off. You should see a quick blip of pressure at key on, then like Mike mentioned the 7-12 psi while cranking.

 

Sounds to me like you have something goin on with the suction side. What did you do for fuel pick up at the tank? What size fuel lines? Double checked all fittings? 

You have it wired incorrectly

 

Why didnt you follow the instructions that came with it

Not sure what glitch you saw on the Carter pump. I do know that using the ECM for a trigger draws very little off of the ECM compared to the stock pump and you would be better served to use it for the trigger for your pump. If the fuse you are using is not a key on hot fuse your pump will not pump any fuel, not sure that the ignition fuse you are speaking of is a key on hot. And if it is if you have  a wreck and a rupture in the fuel system it will just keeping pumping fuel until you turn the key of.

 Hard starting the day after is a loss of prime somewhere in the fuel system.

Fass told me to by pass the ecm due to the fuel pump circuit possibly having issues. I wired it exactly how they told me. On the suction side I have the 1/2" line that came with the pump attached to the factory pickup on top of the tank.

I fuse I used is a keyed hot. I agree with you that there is a loss on the suction side but any guesses where it could be? I have no leaks that I can see.

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On the suction side I have the 1/2" line that came with the pump attached to the factory pickup on top of the tank.

Did you use that stupid wrong tank suction quick connect fitting that fass supplied ?

 

Wrong ! Fass WTF ! ,,,,,,

Wrong

 

'

That is the one thing wrong with their kit. It is a 3/8" to 3/8" and not the proper fitting for a 1/2" push lock hose

 

Do your self a favor and get the correct fitting from Eric at Vulcan Performance. Call him , he know what you need

 

http://www.vulcanperformance.com/Quick-Connect-1-2-x-1-2-Nylon-90-Degree-Push-Lock-p/fqc68pl.htm

 

http://www.vulcanperformance.com/Quick-Connect-s/247.htm

 

Stock photo not exact size

 

 

Edited May 31, 20186 yr by GSP7

You are right on that! My fitting wouldn't go on so I called them and they said I needed to file some off my factory tube so I did. Then it popped on and dripped fuel. So I hose clamped a 6" piece of 3/8" diesel hose then used a 3/8" to 1/2" straight barb and went back to their line.

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I called them and they said I needed to file some off my factory tube

 

Fass needs to put the proper 1/2" pushlock to 3/8" quick connect fitting in their kit

They know its not the correct fitting , but they are pawning the wrong 3/9x 3/8 off on customers in their kits to get rid of their over stock of the incorrect fitting

Yea that’s kinda crap from FASS. I didn’t use their pickup so I never had to worry about it, but that could be the answer to at least half your problem. I would also still wire it up the way the instructions state. Makes no sense to do it another way just because of some possible damage.

I am a bit surprised they would tell anyone to wire a fuel pump to key on hot knowing what might happen in a wreck. I know alot of folks have done it but would not think a company would recommend it. Seems quite risky for them.

I'd never use any kind of quick connector or 3/8" lines. I would upgrade to full 1/2" lines from the tank to the VP44 using Parker Push Lock fittings. 

 

Edited May 31, 20186 yr by Mopar1973Man

AirDogs Kits have all quick connect fitting

 

 

9 hours ago, dripley said:

I am a bit surprised they would tell anyone to wire a fuel pump to key on hot knowing what might happen in a wreck. I know alot of folks have done it but would not think a company would recommend it. Seems quite risky for them.

 

I found out Fass has at least one "employee phone call in installation help tech guy" that they need to fire or demote to trash can emptying tech

 

The owner/manager guy I finally got through and connected to was good

 

 

 

Edited May 31, 20186 yr by GSP7

33 minutes ago, GSP7 said:

AirDogs Kits have all quick connect fitting

 

 

 

That they do and I used them on my install 8 years ago and to date no issues with them. They all fit as they should have.

3 minutes ago, dripley said:

That they do and I used them on my install 8 years ago and to date no issues with them. They all fit as they should have.

 are you refering to the barbed fitting as quick connect fitting?

Just now, Ed ke6bnl said:

 are you refering to the barbed fitting as quick connect fitting?

No. Some look like the one in the FASS photo above and some are different and require a release tool to take apart. About a 50 50 mix. Not sure why AD did not use all the same style.

44 minutes ago, dripley said:

No. Some look like the one in the FASS photo above and some are different and require a release tool to take apart. About a 50 50 mix. Not sure why AD did not use all the same style.

My 8 year old AD just used barbed fittings

 

Even with a new AirDog I would replace all the hose and quick connects.

33 minutes ago, Mopar1973Man said:

Even with a new AirDog I would replace all the hose and quick connects.

I just have not had any problems with what came with it. Might replace one day but not now.

1 hour ago, Ed ke6bnl said:

My 8 year old AD just used barbed fittings

 

Which AD do you have? Could have been different from model to model. Don't know.

Anybody know what hose your kit came with ?

 

My fass came with IIRC Parker Jiffy Flex #7161 or Parker Jiffy #7212

 

Which , talking with Eric at Vulcan, is just a cheaper general purpose hose, not the best

 

Has anyone have hose that is older have surface cracking on the blue outer material?

 

I worked on a guys truck with a older fass and his parker blue color hose was all dried up cracked looking on the outer blue material. Though his truck was caked in dried mud and rocks evyrywhere underneath and never cleaned. Could of been coated with dried mud/water slury that made it look all cracked

Edited May 31, 20186 yr by GSP7