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Filter/snotty sock sputtering

R

Rodd

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Well when it rains it pours. I was planning on replacing my injectors this weekend and the wg solenoid also. Then on Thursday the tranny on my astro van that I use for work went out so I had to use my wifes burb. Spend the day looking for a p30 grumman step van w/ a diesel and found one but that wasted my day. On my way home the old girl started sputtering. Never stalled but I had to fight it to get to 30 mph. I have needed a new fuel sending unit for about a year now but have been putting it off. I have been praying that I don't have to drop the tank yet. I really don't have time this weekend to do it.

Down to the nitty gritty. I replaced the fuel filter in hopes that it is the problem. After replacing it fired right up. No air. Hmmm! I decided to take it for a run around the block. It died this time. Got the air out and it started back up. Drove to a friends house around the corner and I could barely get it to 30 mph. I shut her down and cleared the wg code and it fired up and ran like there was never a problem. I'm going to take it for another run just to check. Anyone think it is the sock?
 
possibly; that is about way mine went, pull off inlet to lift pump, blow air back thru sock maybe 5 psi (don't forget to remove fuel fill cap don't wanna bust a seam or hose on the tank) , reconnect lift inlet & see if it improves, if it does you'll need to drop tank for thorough sock desliming

what kind of pressure you got coming on the filter mgr drain while driving, if you haven't done that check yet you need to, hook up a press/vac test gauge available most part stores JC Whitneys price is $22, valuable piece of gear allows you to check lift & vac pressure, as well as boost if you set up for it to 10 psi

Anyway get one put on a long rubber hose and snake it into the cab taking care to not pinch hose or reading will be "deadheadded", some have taped them to windshield, word of advise used good tape to secure it if that is way you wanna do it save you from looking silly if it comes aloose whicle going down hiway and it tries to beat up your windshield or have the hose come unplumbed and spray fuel all over windshield & hood.

IMO this is only valid lift pump delivery test, some lifts manage to supply 4-5 psi at idle but fall less than 1 psi minimum for loaded engine, healthy lift should sustain 4-5 psi at cruise speed, 2-3 on moderate acceleration or hill climb, on WOT accel may drop to 1 psi or so but should recover fast after WOT speed request has been met.

If that doesn't happen then you need to check lift pump & or tank sock.
 

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I just got back from another test run and it died on me. Got her restarted and home. Opened the t valve and a buch of dirt came out w/ the fuel.

Thanks Tim, I will try and blow back to the sock then pressure test it. I need to get one of those pressure testers. Hopefully one of the auto part stores here locally have them.
 
I shot 3 quick burst of air back towards the tank and then reconnected the lp. Now there is now air pressure or fuel coming back. The LP was working I am going to jump it to see if I get fuel.
 
Well I jumped the lp and got no fuel soooooo, I pulled the tank. Actually it was a piece of cake. 2 long bolts holding the 2 straps that hold the tank up located by the back bumper. And the 3 screws by the gas cap. I shined my light into the tank once I took out the fsu and there was so much crap in there. Also one of the fuel lines broke away from the fsu and had a hole in the wax/top of fsu. Proly where all the crap in the tank came from.

So should I pressure wash the inside of the tank? If so are there any precautions I should take?

Oh, and the sock wasn't snotty.
Thanks!
 
If you've got junk in the tank, then you may have wiped out your lift pump since it's unfiltered from the factory. Luckily your bleeder is from the dirty side of the filter, so most of the dirt should have been stopped at the filter before it got to the injection pump.

Just make sure your tank is good and dry once you're finished cleaning it. Others have done this and will hopefully chime in with some tips. Mine's been clean both times I've dropped it, so I can't help much other than to say that I put a gob of never-sieze around the ring and lines at the top to keep from getting corrosion once everything was back together. I did the same with my fuel line threads, too.
 
I hosed mine out with water hose and simple green, dumped the water as best I could, then swabbed rest with cotton sock (GMCTD idea) attached to end of doubled up coat hangar wire, needs to be stiff & still flexible than swabbed/dried as much as I could sponge out, then took my shop vac hooked to exhaust side and blow hot high volume air in tank to finish dry out.

Snow is correct lift pump mat be compromised, I installed a 10 micron Racor filter in front of my lift pump to prevent crud from taking out the lift pump.
 
Thanks guy's for all the advise. I guess it is off to cleaning before the parts store opens. I had a feeling my lp might be toast.

How hard was it to put the racor filter in? What tools did you need?
 
There is a white plastic thing in the tank. It looks like it is shaped like a U and has a U channel down the center of it. What is it and what is it for?
 
Just my luck non of the parts stores have the sending unit available. Just my luck. The work van is down and the wifes burb is down.

I had heard that the gas engines use a similar model that just needs the filter sock. Anyone know the p/n for that?

Thanks,
 
The gasser model has a provision for a fuel pump on the sending unit.

Can you patch up your old one with JB weld or gas tank sealer?
 
chrisk1500 said:
The gasser model has a provision for a fuel pump on the sending unit.

Can you patch up your old one with JB weld or gas tank sealer?
Click to expand...

It would be nice if I could patch up the old one. It was in pieces 3 pieces. 2 plastic pieces w/ connectors and a large 3 inch cylinder w/ a metal piece going through it. All this in addition to the hole in the top of the unit.
 
BTW I found an easy way to clean out the fuel tank. After some degreaser & Water, I rinced well, poured out excess h2o and had my 7 yr old son stick his arm in and get out all the broken parts and dry it w/ a towel. Then I hooked up my shop vac blower to the fuel fill and ran it for 10 minutes and had him re dry.
 
Rodd said:
BTW I found an easy way to clean out the fuel tank. After some degreaser & Water, I rinced well, poured out excess h2o and had my 7 yr old son stick his arm in and get out all the broken parts and dry it w/ a towel. Then I hooked up my shop vac blower to the fuel fill and ran it for 10 minutes and had him re dry.
Click to expand...

Rodd... Nice to hear you are getting things sorted.. train up your Son to work in the Engine dept... i wish i did it with mine... Like Glow Plug...#8 ++++
Take care
/Paul
 
After installin' any sendin' unit on our trucks, I fill the top of the tank (all around the sendin' unit pipes) with grease. I also coat the bottom of the tank with grease before puttin' it back into the tray. Up here in "salt land" (seems like they don't plow snow here, just lay lots of salt on the road) even new tanks get extremely rusty fast and the top of the tank is a perfect place for crap to sit and rot the pipes out. Usin' the grease seems to cure it.

Here are a few pics of one of the sendin' units I removed. Is the "U-shaped" thing you were talkin' about in these pics? Was it the sock?
 

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teroma25 said:
After installin' any sendin' unit on our trucks, I fill the top of the tank (all around the sendin' unit pipes) with grease. I also coat the bottom of the tank with grease before puttin' it back into the tray. Up here in "salt land" (seems like they don't plow snow here, just lay lots of salt on the road) even new tanks get extremely rusty fast and the top of the tank is a perfect place for crap to sit and rot the pipes out. Usin' the grease seems to cure it.

Here are a few pics of one of the sendin' units I removed. Is the "U-shaped" thing you were talkin' about in these pics? Was it the sock?
Click to expand...

the u shaped thing is actually a square. Chris said it is the baffle.

My question is what is a baffle and what does it do? That is what baffles me):h):h):h):h
 
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