OK, short synopsis. Bought a 74 F100 with a 2BBL 360.Was told the "sock" in the tank was bad so owner rigged up a temporary gas tank in the bed. (a small one)
I drove it home (over 400 miles) having to stop every 40 miles to fill up the little tank. The truck ran a little rough when cold, but seemed ok when it warmed up.
When the truck would start sputtering (running out of gas) I'd pull over and fill the tank with the reserve tank I had.

drive until it starts to run out of gas, pull over, fill up little tank, repeat

Over time, it started running worse, getting harder to start and acting like it was running out of gas when it had plenty of gas. by the last 50 miles it was running horrible like it was running on 4 cylinders. In park it would sound fine when I revved it up a little, but in drive it got REALLY rough like the timing was way off.

It finally limped home, coughing,sputtering and dying every couple of miles.

I figured I fouled some of the plugs so I replaced them, but no change.

I'm gonna get a timing light to check the timing

WHAT NEXT???

Did I ruin it???

 

You might want to check your fuel filter. Running it so low may have glogged it up.

 

This thread will be moved to the fuel delivery forum.

Welcome to FTE!

 

forford,
Did you look down the throat of the carb, while actuating the accelerator to see if the bowl is receiving gas? If you see a healthy squirt of gas, this should eliminate a stuck float or clogged filter problem. If dirt got into the carb, it may have settled in the power valve cavity, which I believe is located on the very bottom of your 2BBL carb. If you believe this to be the problem, you will have to remove the carb. The power valve is located in a small housing on the underside of the carb, held on by 4 small machine screws. The valve cost approx. $3-$4, and you should be able to get one at most parts stores.

As for the filter in the tank, fortunately, the gas tanks on these vehicles are easy to remove. The best way of fixing this is to remove the tank, clean it out, and apply a new filter. This way you can check the tank for rust. If this fixes the problem great, if you're looking for an alternative to pulling the tank, write back I know a solution that may help.
John 24255

 

There is a towing hitch welded to the frame, so I'd pretty much have to take the bed off or tilt one side to get to the opening on the top.

 

forford,
As a vehicle ages, dirt and debris collect in the fuel tank. If the fuel level inside the tank is allowed to go near empty, this debris can collect on the inlet screen or filter causing it to clog. As the fuel pump tries desperately to suck the fuel from this clogged filter, the filter usually collapses restricting the flow of fuel to the pump, and the engine dies as if it were out of gas.

Again, fuel tank removal and filter replacement is the preferred method of resolving this condition. However, since removing the tank is not an option for you, here is an old trick of mine that may help:

First, remove the gas cap from the fuel tank. Also remove the rubber fuel line from tank to the fuel pump, at the pump. Place the nozzle from you air compressor hose into the fuel line, blowing air back into the fuel tank. I use a short blast of 125-PSI pressure. This will blow the filter or screen off the end of the fuel pickup tube inside the tank. When the line is clear, you should hear the bubbling sound of the air in the tank. When you hear this, the gas should flow freely. I would install a good in-line fuel filter either between the tank and pump, or between pump and carb. This should help keep the carb clean. Never use this trick on fuel injected vehicles since their fuel pumps are located in the fuel tank.
Please let me know if this trick works for you.

Keep on trucking,
John 24255

 

All,
1. I would not recommend blowing the tank filter off the fuel line pickup. This is a hack move and does not represent "good practice" with respect to vehicle maintenance. The tank must be removed. Cut the hitch off and remove or replace the tank. Replace the intank filter.
2. Secondly, There is a filter that screws on to the carb. Go to the store and buy three or four of them. From the sounds of this, your going to need them.
You cannot hurt the truck by running out of gas unless you have an electric fuel pump, which you don't, right? It is possible to suck solids in the carb into the main jet when running the bowl dry. I doubt this is your problem. When the main jets are clogged remove the top plate of the carb and clean out the bowl. Spray carb cleaner through the jets and ports. Ensure the needle seat assembly is clear and reassemble.
You'll be fine,
KingFisher

 

I think ya'll didn't read the original post closely, the tank is completely bypassed.
A 6 gal. plastic boat tank is connected to the fuel line sitting in the bed off the truck. No rust in there.(its plastic) no debris either (I can see in it)
anyway....

I got the distributor loose enough to turn and it seems to run a little better. I don't have a timing light yet, but hopefully when I set the timing it will solve the problem with the engine running rough.

Then, on to getting the gas tank back in working order.

Thanks to ALL who responded. Its not easy to diagnose a truck via the internet, you guys rock!

-Danny

 

John 24255 is right. Just blow the sock off with air and put a micron filter near the tank. This is an easy fix and I have done it a couple of times. This way the sock is external and can be easily cleaned when it plugs again.

 

wb6vvv,
Thanks for the feedback. I have been wrenching on cars and trucks for longer than I dare remember, and believe it or not, I have managed to learn a few helpful things along the way. I am somewhat reluctant to give advise on quick fixes because there is always someone out there who will jump all over them. However, considering the circumstances, this solution was far less expensive, less time consuming, and presented far less potential risk of injury to the truck and especially the owner. I don’t know about you, but my cheeks always tighten up when using a cutting torch or cut-off wheel around a gas tank, especially on older vehicles that may not have a sealed fuel system or have old seals that leak vapors.

Again, thanks for the encouragement; if more of us share the things we’ve learned, all of us will be a lot wiser. Hopefully, this is the primary purposes of this website, and the advantage of the tremendous communication opportunity the Internet provides.

Thanks,
John 24255