IP issues

[chillman88]

Completely rewriting my first post to better explain.

I got home today and noticed a fuel leak. Tracked it down to the IP cover, it's been missing a screw and I had previously neglected to replace it.

I drilled out the screw and tapped it with a 1/4-20 and put a new screw in.

I checked to make sure the fuel shutoff was clicking. It was.

I put it all back together and it started just fine. I shut it off to verify the shutoff was functional. It shut off fine.

I started it back up. It idled just fine, then tapered off and died.

I let it sit a minute, with the key on so the e-pump would continue to run.

Truck started right up FINE. Not acting like air in the lines or anything. Then after a few seconds, it tapered off and died again.

It's acting almost like it's getting fuel, but not enough to stay running. Pressure but not volume? I don't personally suspect the pumps since it was running FINE. I drove it home from work, that's when I found the leak.

I tapped the IP and put the screw in. Reinstalled the cover and bam, won't stay running.

 

[chillman88]

Ok scratch that. Its snapped off flush on the bottom piece. It was like that when I bought it. Should have dealt with it right away. Guess I'll have to drill and tap it.

 

[chillman88]

Alright...

Truck starts fine, idles fine, then slowly dies like its running out of fuel. I still have pressure at the schreader valve when it dies. No idea how much, but it "should" be getting fuel still.

 

[idiTravelAll]

Wish I could help but I'm here to learn, if I had to guess I'd say air in your lines.

 

[chillman88]

Wish I could help but I'm here to learn, if I had to guess I'd say air in your lines.

I thought of that but it fires right off every time even after it dies. Kinda makes me think I need a new fuel pump...

 

[chillman88]

Ok so if anyone re-reads this. I completely rewrote the first post to make sense of what has happened.

 

[Fordfan90]

I thought of that but it fires right off every time even after it dies. Kinda makes me think I need a new fuel pump...

How long has the fuel pump been on there?

 

[chillman88]

How long has the fuel pump been on there?

That's an unknown. At least a year. I'd question it more if I hadn't just driven home with no issues other than a leak. It sounds and feels like it's working. It's definitely pushing fuel through the system.

Now that I've finally conceded defeat for the night and calmed down, I'll go do a volume test in a few minutes.

I checked the oil when I got home and there are no signs of diesel in the oil.

 

[Fordfan90]

That's an unknown. At least a year. I'd question it more if I hadn't just driven home with no issues other than a leak. It sounds and feels like it's working. It's definitely pushing fuel through the system.

Now that I've finally conceded defeat for the night and calmed down, I'll go do a volume test in a few minutes.

I checked the oil when I got home and there are no signs of diesel in the oil.

Sounds like it's getting air from somewhere maybe injection pump? But it's weird that it ran fine for you then you fixed the fuel leak then it's starts then dies.

 

[chillman88]

Ok so riddle me this.

I'm getting fuel at the Schreader valve on the filter, but none coming out the return line from the IP. Doesn't make sense? Shouldn't (if the fuel shutoff has power) any fuel pressure from the filter head push through the IP and recirculate?

 

[Thewespaul]

Ok so riddle me this.

I'm getting fuel at the Schreader valve on the filter, but none coming out the return line from the IP. Doesn't make sense? Shouldn't (if the fuel shutoff has power) any fuel pressure from the filter head push through the IP and recirculate?

In theory yes, unless you inlet screen is clogged

 

[chillman88]

In theory yes, unless you inlet screen is clogged

Inlet screen shouldn't clog suddenly like that though I wouldn't think...

It could be possible the pump just plain died. It's just really coincidental timing is all....

Depressing the schreader valve and filling a plastic bottle I get less than 1/2 pint in 15 seconds, which is below spec. Still, I would expect to see some out the IP return line...

Unless the pump is putting out just barely enough pressure to "move" the fuel and not enough to pressurize it. 1psi would come out the valve, but might not pass through the IP...

 

[chillman88]

Well... I ordered a new lift pump. It'll be here tomorrow afternoon. The wife will run me to work (UGH) but hopefully I can get it changed out tomorrow night. I'll probably just bypass the electric pump for now.

 

[gandalf]

Check your fuel flow coming out of the filter head. I believe the schraeder valve will give you lift pump flow, measured before the fuel goes through the filter. If you have fuel coming out of the filter, going to the IP, then I'd say your problem is the IP.

 

[chillman88]

Check your fuel flow coming out of the filter head. I believe the schraeder valve will give you lift pump flow, measured before the fuel goes through the filter. If you have fuel coming out of the filter, going to the IP, then I'd say your problem is the IP.

Yes indeed, however I'm technically under spec at the valve, so I'd most certainly be under spec after the filter.

I even removed the check valve on the IP outlet and only got a small drizzle with the pump running. The filter is only a year old but if a new lift pump doesn't fix it, I'll put a new filter on anyway.