Sputtering under load - quick help pls

[phlegm]

Good Morning guys,

Had to cancel my appt for tires and alignment this morning. Yesterday I went to go for a drive and pickup a new headlight, getting excited that we were registered and legal and ready to go (my first mistake). SO heres the story tell me what you guys think.

1. Truck sat with VERY little gas in it for years
2. Got spark and put 5 gal of fresh gas in, got it to crank.
3. Fuel gage stuck on empty
4. Got suspension work and carb rebuild done, took it for a drive
5. It stammers and sputters a bit at first, while driving a half mile or so. Stopped, checked my bad tire, got back in ran a lot better.
6. Got up to 50 MPH after that at one point drove about 3 miles to a friends house and back, no problems.
7. Got in truck yesterday, cranked fine rolled out of neighborhood fine (low speed).
8. Got out of neighborhood, it sputterd some but still got up to 40ish....
9. Got on highway, sputtering got progressively worse and it would not allow me to gas it at all without almost stalling.
10 get to parking lot, I can rev it in neutral with little to no sputter.
11. Almost didnt get out of lot on highway... .got to 35 MPH but it was struggling and I had to do it very very gradually.

Here are my thoughts, since it ran so well the other day I think the carb rebuild is a good one. Since the gas gauge doesn't work and it sat with very little gas in it I wonder if the fuel sock in the tank got crusty and is bad. I want to check it this weekend but dont own a tank ring tool, and cant find a locally sourced fuel sock.

Here are the questions
am I on the right track?
how do I get the sender out?
What am I looking for in a "good Fuel Sock"?
If it is fuel related, how do I know if the tank is corroded?


Thanks in advance,

[Jrainman]

the sending unit .first disconnect the fuel lines off the sending unit then electrical wire, you will see a locking ring surounding the sending unit, tap it with a blunt scrwdriver or punch, move the ring from the tabs that hold it in,then pull sending unit

I think you will need to give more information about your truck engine size, carburator brand 2 or 4 barrel , did you check your fuel filter , was the fuel pump changed is it putting out the right amount of pressure for the carb you have .

im no expert but you might be headed in the wrong direction you might be getting to much fuel but you would need to fill in the blanks before getting some good advice here from the carb guys

[HO455]

Sound like you are on track. Do a search for fuel sender removal there are lots of threads on how to do it. I personally have never used a fuel ring tool, just a punch and a hammer to tap the ring loose. Take your time and go from side to side. Use a small mirror and a flashlight to inspect the inside of the tank. If you have a parts store that is decent you should be able to find a sock off a different vehicle that will work.
Good luck!
What engine/ carburetor do you have? There should also be a filter in the carburetor inlet that you should check.

[phlegm]

thanks guys, its the 350 with a quadrajet. The Carb just got rebuilt, so I think I am good there. of course for 3 bucks I willprobably go ahead and change that fuel filter again if I find the sock is rotted or stiff. that way I have a fresh start and can isolate the fuel pump.... if its truely a fuel issue.

I think for good measure I will siphon the gas thats in there. the old gas had stabilizer in it, so I dont *think* thats the problme cant hurt

[HO455]

I found this video which should help you.

https://m.youtube.com/watch?v=d-vPZ2RXWZI

[phlegm]

awesome! So with a mirror and a flashlight (sounds fun) what should I be looking for in the tank that makes me swap the whole thing out?

[phlegm]

Originally Posted by HO455

I found this video which should help you.

https://m.youtube.com/watch?v=d-vPZ2RXWZI

for the record everyone should watch at least the last minute of this video, its awesome.

[HO455]

RUST! It is the worst problem. It collects on the bottom of the tank and over time causes leaks. Ideally it will be clean metal with no debris. Hopefully you are some where between the two extremes.
Now days there is the high tech way with the small cameras on a flexible wand to inspect areas like fuel tanks or cylinder bores.

https://www.amazon.com/Borescopes/b?...node=401578011

Good luck.

[HO455]

Originally Posted by phlegm

for the record everyone should watch at least the last minute of this video, its awesome.

I had quit watching when he was headed out of the garage.

[randy500]

Could be as simple as a cracked or bad fuel line that is sucking air. Have you checked the rubber fuel lines under the cab and at the fuel pump.

[Boog]

Have you pulled the spark plugs to inspect them or the dist cap? It could be the advance weights are stuck after sitting for so long. It can run the same way as yours. As far checking the fuel output you can disconnect the line at the carb and put it in a can to watch it as someone turns the engine over.

[whtgmc68]

I had the same issue with my truck when I first bought it when I lived in CA in 2010. It would run great one day and then bog down and nearly stall the next. I was tinkering with it anyway so I put on a new carb, converted to electronic ignition, changed the fuel filter and put on a new fuel pump and nothing worked. Swapped out the fuel tank and never had another issue and the truck ran perfectly until I pulled the 350 for my 383.

You would not believe the amount of sediment that came out if the old tank! I guess it would slosh over the feed line sometimes and block the flow of fuel.

[phlegm]

I think I have it figured out... LOL

May as well swap the gas tank, by the time I pull it and find the float, debris etc.... This truck is going to be driven by my son, while I think all kids should learn to deal with roadside problems I at least want to give him a good start.

**Edited**if you saw my original post u saw my idea about using compressed air to clear the lines. I decided against that because the fuel pump is in line. I'm just going to hook everything back up to let it run for a little bit and then after it's had time to clear the fuel lines to the fuel filter on the carb change the carb fuel filter.

thanks for all the help! tank and sending unit being ordered today!