New lift pump, still now preasure
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From: Durham, NC
New lift pump, still now preasure
Working on a 01.5 2500 HO 6 speed
We just put in gages and found the LP was not working. Put a new LP in this morning. It seems to be working fine, but has trouble building preasure. When we crack the line there is fuel coming out, but the guage does not build preasure. After going through this prosses a few times I get a good bit of air out and the pump builds 15 lbs. Close the line, bump the starter again and nothing, no more preasure. Fuel filter is new, all lines and fittings have been triple checked. It seems like it is still getting air in somewhere. I am sure the injection pump is on its last legs, if not already dead, but we should still see preasure at the gauge.
Any input or tips?
We just put in gages and found the LP was not working. Put a new LP in this morning. It seems to be working fine, but has trouble building preasure. When we crack the line there is fuel coming out, but the guage does not build preasure. After going through this prosses a few times I get a good bit of air out and the pump builds 15 lbs. Close the line, bump the starter again and nothing, no more preasure. Fuel filter is new, all lines and fittings have been triple checked. It seems like it is still getting air in somewhere. I am sure the injection pump is on its last legs, if not already dead, but we should still see preasure at the gauge.
Any input or tips?
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Have you tried putting a mechanical test pressure gauge directly on the injector pump to verify actual pressure? It would not be the first time a fuel pressure guage isolator sending unit was bad out of the box. Could be that you have good pressure but the guage is indicating in error.
If you have eliminated the possibility of an gauge indicating problem, try purging the fuel system at the injector pump until you get no air. This may make a mess and require a few quarts of fuel to be bled.
Another possibility is the factory OEM fuel tank draw straw assembly is leaking air into the fuel system. If this is the case the Vulcan Draw Straw kit addresses this problem very nicely.
If this still does not resolve the problem, try a new lift pump.
Your sig says you have a FASS 150. I am going on the assumption that this is no longer the case?
If you have eliminated the possibility of an gauge indicating problem, try purging the fuel system at the injector pump until you get no air. This may make a mess and require a few quarts of fuel to be bled.
Another possibility is the factory OEM fuel tank draw straw assembly is leaking air into the fuel system. If this is the case the Vulcan Draw Straw kit addresses this problem very nicely.
If this still does not resolve the problem, try a new lift pump.
Your sig says you have a FASS 150. I am going on the assumption that this is no longer the case?
Thread Starter
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Joined: Feb 2006
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From: Durham, NC
This is not on my truck.
No fuel preasure isolater.
The gauge line runs straight from the banjo bolt on the IP to the back of the gauge. The truck is getting air in the system some how just cant figure out how.
How difficult is the draw straw to get to?
No fuel preasure isolater.
The gauge line runs straight from the banjo bolt on the IP to the back of the gauge. The truck is getting air in the system some how just cant figure out how.
How difficult is the draw straw to get to?
Thread Starter
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From: Durham, NC
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From: Middletown In.
It's in the fuel tank EI the pipe inside. It may or may not have a filter bag on the end of it. Also make sure you don't have a pinhole in your supply line from the tank to your LP. Sometimes they rub a hole in them from vibration.
Mark
Mark
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The draw straw is in the fuel tank. The tank must be dropped to access the draw straw. The Vulcan Draw Straw Kit:
http://www.vulcanperformance.com/ser...2%84%A2/Detail
http://www.vulcanperformance.com/ser...2%84%A2/Detail
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How much fuel is in the tank right now? My reason for asking is that if the leak is in the draw straw and the tank is empty or low; filling the fuel tank up with fuel will eleaviate the issue for now but the air leak problem will have to be addressed.
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From: Durham, NC
Got it running.
after alot of checking we everything seemed fine. We checked the preasure coming out of the lift pump going into the fuel filter. It was fine, 15 lbs no problem. This means it has to be the new filter or the line coming from the filter running to the injection pump. Replaced the line first...nothing. Pulled the filter out, 15 lbs of preasure. Hmmmmm... Went to Napa, told them the the situation and they exchanged the filter for another new one. Put the new on in and everything is fine, 15 lbs of preasure. The lift pump was no doubt bad, but all this other mess was because of the filter.
after alot of checking we everything seemed fine. We checked the preasure coming out of the lift pump going into the fuel filter. It was fine, 15 lbs no problem. This means it has to be the new filter or the line coming from the filter running to the injection pump. Replaced the line first...nothing. Pulled the filter out, 15 lbs of preasure. Hmmmmm... Went to Napa, told them the the situation and they exchanged the filter for another new one. Put the new on in and everything is fine, 15 lbs of preasure. The lift pump was no doubt bad, but all this other mess was because of the filter.
Guest
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Good to hear you got her running. I didn't realize you also replaced the filter too. In the future it is best in my opinion to manually fill the fuel filter canister with diesel fuel just short of the top so when you thread on and tighten down the filter canister top, a little fuel runs over the sides. This ensures no air is in the fuel filter canister. A perfect brand new lift pump does not have the power to purge the air from the fuel filter cannister.
If you just replace the fuel filter and bump the starter to prime the fuel filter canister without manually filling it, the injector pump will run dry of fuel and the engine will immeadiately stall upon start up.
Then you get to have fun purging the fuel injector lines individually from the fuel filter canister all the way up to the cylinder head.
I use a small 2 oz. 2 stroke fuel mixing syringe I bought at Walmart for about a $1 to fill the fuel filter canister after I replace the filter.
Be sure to inspect the fuel filter canister house inside on the bottom for very fine metalic shavings if the lift pump has failed. The lift pump circulates the fine shavings when it craps out from wear and they get caught in the fuel filter & canister.
If you just replace the fuel filter and bump the starter to prime the fuel filter canister without manually filling it, the injector pump will run dry of fuel and the engine will immeadiately stall upon start up.
Then you get to have fun purging the fuel injector lines individually from the fuel filter canister all the way up to the cylinder head.
I use a small 2 oz. 2 stroke fuel mixing syringe I bought at Walmart for about a $1 to fill the fuel filter canister after I replace the filter.
Be sure to inspect the fuel filter canister house inside on the bottom for very fine metalic shavings if the lift pump has failed. The lift pump circulates the fine shavings when it craps out from wear and they get caught in the fuel filter & canister.
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