Air intrusion or fuel starvation?

[Laine D]

Hello. This forum has become extremely helpful in the past year I’ve been working on my truck. My issue today is I’m trying to get to the bottom of my truck sucking air and then it starving for fuel. I have a facet duralift, 9-11.5 psi pump. I bought it after reading the article on here and figured it was a good buy. Now I’m kinda debating weather or not it is so good. Ever since I put the pump on it had been fine for about 3 months. A couple weeks ago I did the shower head fix thing in the tanks. Got as much as the crap out as I could and put it back together with a new selector valve. Blew out all the lines and so forth. It ran great for about a week. I drove it pulling a 14000 pound forklift Through the sierras and Into Nevada and back and cruised 70 on the flat ground. Truck didn’t care. Once I got back I found out that something pretty bad must’ve happened or I messed it up because I am getting massive amounts of air and restriction on the front tank. Driving on the rear I don’t get as much air but at least once I day I will hit the little shraider valve on the filter and it’ll blow air for 1-3 seconds then a steady stream of fuel. I don’t have any return line leaks on the motor and all the fuel connections on the way back seem fine. Some days there isn’t any air in the filter either. Even when there isn’t any air it will fall on its face at anything over 2000 rpm and at any cruising speed I can feel it surging. The pump has a clear bowl and sometimes the fuel level in the bowl is about half way full. Looking at the pump I realized that the pickup only gets to the fuel when the bowl is at least at 3/4 full. I don’t have a fuel psi gauge but I’m assuming it’s pretty bad psi. I will be getting one soon. Does anybody have any idea what this could be? I’m already planning on converting to a single tank to get rid of all the extra stuff and have room where the front tank is to have a better E fuel setup.

 

[IDIBRONCO]

You get more air into the system while using the front tank. This could mean that the FSV is causing the sir intrusion. Some people don't have very good with the Facet pumps. The quality doesn't appear to be very good these days. Thesingle tank conversion would eliminate the FSV for sure.

 

[Laine D]

You get more air into the system while using the front tank. This could mean that the FSV is causing the sir intrusion. Some people don't have very good with the Facet pumps. The quality doesn't appear to be very good these days. Thesingle tank conversion would eliminate the FSV for sure.

I want to believe that the facet pump is good because it was great for a little while but maybe it was like a honeymoon. I feel like the single tank conversion will eliminate weak links and clear up some space.

 

[Laine D]

I want to believe that the facet pump is good because it was great for a little while but maybe it was like a honeymoon. I feel like the single tank conversion will eliminate weak links and clear up some space.

Also, for everybody reading my post asking how much the truck is worth... ignore my posts like these haha

 

[IDIBRONCO]

I've also seen people say that the fuel bowl on the pump can be (or become?) loose. They have air intrusion issues until they tighten the bowl up. A fuel pressure gauge will tell you how your E pump is doing.

 

[Laine D]

I've also seen people say that the fuel bowl on the pump can be (or become?) loose. They have air intrusion issues until they tighten the bowl up. A fuel pressure gauge will tell you how your E pump is doing.

I believe I got the bowl pretty tight. I will get a fuel psi gauge soon

 

[Laine D]

I've also seen people say that the fuel bowl on the pump can be (or become?) loose. They have air intrusion issues until they tighten the bowl up. A fuel pressure gauge will tell you how your E pump is doing.

I just realized, I have the pump mounted in the engine bay. I know that these are supposed to be able to pull pretty far but could the placement be effecting pressure?

 

[Laine D]

Well I found out that my brand new selector valve was clogged once again. Even with the inline filters that were placed before it. Anyways. Currently in the process of getting rid of the dual tank system and going to a 38 gallon rear tank. Will remove the front tank and build a dual filter type system that I can tuck up under the frame where the front tank used to be.

 

[Cubey]

(Nevermind)

 

[IDIBRONCO]

Well I found out that my brand new selector valve was clogged once again. Even with the inline filters that were placed before it. Anyways. Currently in the process of getting rid of the dual tank system and going to a 38 gallon rear tank. Will remove the front tank and build a dual filter type system that I can tuck up under the frame where the front tank used to be.

I guess you've figured out the problem and solution. And the final answer is fuel starvation.

 

[Cubey]

I wonder what the design is of aftermarket valves that they clog so easily. Or maybe my two IDIs are just oddballs.

 

[Laine D]

I guess you've figured out the problem and solution. And the final answer is fuel starvation.

Yessir. Weird how air intrusion and fuel starvation will kinda act alike, at least in my situation they did.

 

[IDIBRONCO]

Yessir. Weird how air intrusion and fuel starvation will kinda act alike, at least in my situation they did.

Technically, they are related. They both result in less fuel while the engine is running, just in different ways.

 

[Laine D]

Technically, they are related. They both result in less fuel while the engine is running, just in different ways.

Makes sense. I plugged off the line from the Return lines to the filter head and I haven’t noticed anything different. I read some warnings about it over pressurizing the return system but I can’t quite understand how that would happen. Nothing has exploded yet in the last 2 weeks.

 

[IDIBRONCO]

I don't think that would happen. As far as I know, it just make it harder to get all of the air out of you fuel filter. If I'm wrong on that one, someone will let us know. Even then, it can't cause the return system to over pressurize since there is an outlet at the back of the engine that drains back to the fuel tank.