Crank but won't start losing prime

R

richsdieselperf

Lethal Injection
Like the title says I have a 03 that will crank but will not start if I pump up the hand pump/ bleed air out the pump will get very hard but will go completely away if i let it sit for 5 minutes and if I go to crank the engine it loses the prime instantly.
I have changed the filter, put air in the tank to try and find the leak and still none found, if I spray some GAS in the intake the truck will start off it and will continue to run all day on it's own with plenty of power but as soon as i shut if off im back to the same thing aggain
 
This truck did have a P1093, and A P0090 code, I replace the FPR and the fuel pressure sensor and the codes have not returned. It sure seems like the truck is sucking air some where but i can't find qny leaks ANY where, so far. Any one else ever ran into this problem?
 
It's really pretty simple. There is an air leak in the fuel system that's allowing the fuel to drain back to the tank...end of diagnosis. Check for dry cracked fuel lines on the engine, improperly installed fuel filter, a bad primer pump, etc.
 
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1lowdiesel said:
X2.

I'd say just put an Airdog or Raptor on it and be done with it. That will prime the system by itself and with the AD you can eliminate the filter housig all together.
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Shhh that's what I like to do! LOL Sometimes the customer does not see a way to justify the cost. :doh:
 
Fuel mileage and never having to pump the primer or buy a $40 fuel filter again isn't enough justification lol
 
The truck has a new filter. Iam thinking about puting a new
Filter head and new filter on it and buying some new fuel line hoses, it's just frustrating I can't find where the truck is sucking air! Iam tempted to cut a spot of the fuel supply line out from under the truck and puting a electric lift pump in it's place to see if it's sucking air before the fuel filter because I'm just not sure at this point.
 
Put an Airdog on it and be done. I would bet the farm it's leaking from the filter housing. Don't waste money on another filter and housing b/c with the AD you can bypass that stuff. Trust me i've been there.
 
Oh don't doubt me I deffintly trust you but the guy who owns it, a good friend of mine just wants it fixed so he can sell it with the least amount of money on it as possible wrapped up in it the filter head is $200 cheaper and less work involved so I think first I'm going to put a small electric lift pump to bypass the filter head if I can to see if that fixes it, if it does as much as I'd like to put an Airdog on it, I'll probly end up having to put a filter head on it.
 
Might be the o-rings in the filter, although that sounds like a pretty quick leak down... One of the admin over at dmaxcentral.com is selling an o-ring kit to members for like $11 or something like that shipped!!! We redid mine and it is a lot better but not 100% perfect, but hey it is a 350,000 mile rig so its good for now... An AirDog or FASS will be in its future...

I wrote it up and it will be in the June or July issue of Diesel World... It is a pretty easy rebuild.
 
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richsdieselperf said:
Oh don't doubt me I deffintly trust you but the guy who owns it, a good friend of mine just wants it fixed so he can sell it with the least amount of money on it as possible wrapped up in it the filter head is $200 cheaper and less work involved so I think first I'm going to put a small electric lift pump to bypass the filter head if I can to see if that fixes it, if it does as much as I'd like to put an Airdog on it, I'll probly end up having to put a filter head on it.
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if you need a filter head let me know i have a brand new one off an 08.

Bustedknuckles said:
Hate to hijack but since I have an airdog I may as well delete the filter head on my truck? What are the pros and cons?
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Cons... NONE.
pros... never having to pump the primer or buy a $40 fuel filter again.

Chris Tobin said:
I wrote it up and it will be in the June or July issue of Diesel World... It is a pretty easy rebuild.
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Very cool
 
Well just now I put a regular fass lift pump in place of filter head and it's starting everytime. I'll let you know what the guy says if he wants Stock head or go with an airdog I'll let you know either way thanks for all your help
 
Well I got a good new filter head the owner bought me one it is new tho anyway put it on and it started many times then tried a restatart, no start so I pulled the hose off the inj pump inlet and put a hose in a bucket of fuel started many times I replaced the whole hose from filter head outlet to inj pump started many times then no restart, tommorow Iam going to put 2 clear hoses on both sides of the inj pump and look for air that way I can be totally sure it's air or not if not I guess the pump has to be bad right??? All injectors have good balance rates I have not done a return rate test yet and I'm not planing to either this truck is a nightmare!!!!
 
I sure hope the brand new filter head is not cracked lol it's form dmaxwrenchkit.com and is not losing fuel under bleeder screw anyway hopefully the clear tube will help mr tommorow.
 
Just bypass the filter head for testing and that will let you know if that's the cause of the air leak. All yoou need is a small piece of tubing to do it.
 
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