Hey Guys - New to the forum and have a problem that hopefully somebody here has experienced. I have a 1970 Ford 1-Ton Camper with a 390 Engine with a 2 barrell Holley carb. The truck sits for about 11 months and then I take it out on a camping trip. The engine has been fairly bullet proof, but I am having a bit of an issue. Normally, after I come back from the trip (~1,000 miles) I fill the gas tank to prevent water and rust from forming in the gas tank. Last year I neglected to fill it - UGH! When I filled it up later I put about 46 gallons into the around 50 gallon tank. Here goes my story:

So, I got it out of storage this morning, it started right up so I thought all was fine. I drove it from my storage location to the freeway (about 3 miles - easy driving - mostly downhill), and again, everything seemed totally normal. I was driving down the freeway and I lost all power. I could pump the throttle and it would kinda come back to life and then die again (I'm thinking the accelerator pump added some fuel to the carb), pump the throttle again, a little more life, and then nothing again.

I pulled over to the side of the freeway after it had completely died and started thinking through what could be wrong (I hadn't thought about it being out of gas at this point). I have an inline electric fuel pump on a switch that I normally use just when starting the truck, so I turned it on thinking that maybe the mechanical fuel pump failed. I was then able to get the truck restarted. So I got back on the freeway, and I thought all was good. I was only about 1/2 mile from my exit so thought I should be safe. Once back at freeway speeds, I had the same problem. Pulled over, waited a few minutes, left the electric fuel pump on and it started right back up and sounded fine. I got off the freeway, and started driving up the small hill to my house - same problem - hesitation, but I was able to keep pumping the gas to get it up the hill. I got to the top and it died, I coasted down the other side, came to a stop and was able to get it going again. From there I decided that I must be out of gas, so I limped it to the nearest gas station and filled it up - 46 gallons into the aprox. 50 gallon tank. At this point I figured I had just been dumb and ran the thing out of gas. So I drove it back home (about 1/2 mile) and thought all was fine.

A couple of hours later I decided to go and test it one last time. And everything seemed OK while driving around on the streets (drove a couple of miles around my neighborhood). I then got back on the freeway, and I experienced the same problem again. Hesitation and then dead. Again, was able to restart and get it home, on the way I decided to drive around the neighborhood again, 5-6 miles without problem.

It seems that it us only having the problem under heavier loads. Any suggestions on where to start? I was thinking maybe there is some water in the gas from sitting nearly empty for the last 11 months, or that it could be a clogged filter. Any opionions out there? Thanks for the help!

 

Welcome to FTE!

Possibles, which you have already hit on to some degree.

--Debris in the tank building up on the pickup filter. This slows the flow, you stall, the debris falls off. Repeat with each driving cycle.

--Lazy fuel pump. Check your oil, make sure it isn't pumping gas into the crankcase as a bonus.

--Water. That tends to cause a poor running condition, although some filters won't pass water, so that would lead to a stall after running.

And my favorite, all of the above.

Start at the carb, and check for water and debris inside, then down the line to the tank. You may have to pull it and have it steam cleaned inside. You will also want to check the fuel pressure coming out of your pumps. 7-8 psi iirc.

 

Thanks for the quick reply. The tank has two sections and two pickups. It seems to be happening using either of the pickups - I will see about installing an inline fuel pressure guage that I can read during driving to see if that will help to identify the problem. I also got some of the alcohol based water disolver. I'll try changing the filters to see if that helps...