Lift pump ?

[rodman68]

My filter light came on again just changed the filter had approx 250 miles what the heck. Did notice that there was junk in the bottom of the filter also remembered just started to use the rear tank. Dumped the filter and it had milky stuff in it and the fuel on top after settling was very cloudy. I havent used the rear tank since I bought truck and I have a feeling the po used some very bad bio that still has soap in it. Noticed that new fuel filter is half full and it looks like lift pump is bad. I am concerned about the fuel lines so I hooked up my carrier electric pump and at first it pumped some gunk, but then looked ok I had switched to the front tank. But noticed that It only pumped 5 gallons in 15 minutes seems real slow, does this seem slow? I ran it on the excursion and I know it pumped faster than that I wonder if the lines are partly clogged? Is it ok to use compressed air to clean out lines?

 

[plywood]

I think the Carrier pump is 32 gal/hr. if IIRC.

So thats 8 gallons in fifteen minutes, but I'm not sure if that is at no pressure or rated pressure and I supposed it may not make a big difference.

In any case, if that tank has been sitting partially empty for a while it could be full of algea and condensation and who knows what else.

Running compressed air backwards is a little risky unless you an reg it down really low.

I've heard of guys putting some acetone in and then blowing that back but I think I would want to pull the tank and clean from what you're saying.

 

[rodman68]

Noticed the front is plastic and the rear tank is metal wonder if the front tank has been replaced didnt think they put in plastic in the 94 model year. Is it a pain to drop the rear tanks wonder if I should do both. That would work out to 20 gals an hour, I think it was around 5 gals to 10 minutes with the excursion so 30 gals an hour wonder if its due to the longer fuel run?

 

[plywood]

Could be a rubber line sucking together or crud in the selector valve from the broken up pickup, who knows.

Most guys prefer to remove the bed and then you can do both tanks without all the problems.

Some trucks of that era did come with a plastic and a metal tank.

 

[rodman68]

no way to lift bed out I will need to drop it down. The rear tank only has a couple gallons in it. If both the tanks are out is it ok to shoot compressed out in reverse thru the fss to both tanks.

 

[plywood]

Well probably with low enough pressure and hold the ummmmm shoot words words pistol thing a ways away from the hole so the pressure is even less.

I wouldn't try to use enough pressure to blow stuff out, let the acetone or seafoam do the work.

Personally, I just took out the rear tank and ran all new lines to and from the front tank and skipped the selector valve. With my homemade pickup I can use at least 17.5 gallons from my tank.

Some guys aren't using much more than that out of both tanks. No offense, some guys.

 

[rodman68]

I will find out tomorrow how the rear tank is looking maybe the front is ok. Not a bad idea clean the tanks then run seafoam to clean the lines I don't think they are clogged just maybe lined with crud or film. I am adding two small pressure gauges one will the tee off the air valve and the other tee from the fuel filter vacuum sense switch to keep an eye on the lift pump and pressure drop from the fuel filter. Never pulled these tanks before is the pickup on the bottom of the tank? What I was thinking I could use the carrier pump to drain the front tank to the bottom.

 

[plywood]

The pickups are on the bottom but they are typically broke off so you can only get down to 1/4 tank. Your truck is newer so maybe not.

You can pull out the pickup/sender assembly and attach a piece of hose with a fishmouth on it to get to the bottom.

I assume you know what a fishmouth looks like being a pirate and all.

Here is what I did.

 

[rodman68]

just got the tank down and about to drain the rest of fuel it actually looks like it has sand in the bottom and some white goo but at first glance no rust. I am not a pirate i am achmed the terrorist.

 

[plywood]

In that case I would think Homeland Security put marshmallows and sand in your tank to foil your plans.

 

[rodman68]

Ok I will take that back then im a pirate. yes its sand not a whole bunch but thats what it looks like. No rust in the bottom is the good news I will try and use a rag to get the junk out or should I use some type of cleaner? The pickup tube is intact but the screen has that white paste stuff in it. I am thinking I should do the front tank after this one is done.

 

[plywood]

Honestly I have no idea what the paste might be, maybe someone who has ran alternative fuels might know.

But, yeah sounds icky, probably some cleaner and lots of paper towls.

 

[rodman68]

I suspected the previous owner tried to run either svo unheated or some very bad biodiesel in it. Well the bad news is under the pickup tube there is some rust that has unfortunately gone thru with some very small pin holes. Not sure if could be patched or a new tank is in order, I am planning on selling this truck due to its size. A major pain getting stuff on and off this thing, would like a one ton 2wd.

 

[rodman68]

got it back on the road again I cheated and filled the pin holes with jb weld website says it will hold up to diesel, that was a pain to get back in. I didnt do the front tank but when I was draining the rear with electric pump I noticed when the tank is almost empty thats when the crud comes thru. So what I did was run the electric on the front tank to drain it added a few gallons of used filtered atf in the tank let it sit overnight pumped that out. My built in pressure gauge shows 5.5psi at idle. A few things i notice when starting cold it fires up quicker but it surges most likely air but its still doing it after a week should air be pushed out by know? It does that for a couple seconds then runs smooth other good thing is it doesnt throw out the puff of smoke at startup anymore. I still need to replace the return lines on the injectors because they are original could be my air intrusion issue!

 

[hesutton]

Glad to hear you got it back on the road. But, it does sound like an air leak with the surging you are having. I agree that the return lines/caps are a good place to start looking for fuel/air leaks.

Heath