advise needed from the shadetree

[oaktownjc]

Hello, 1st ever post, thanks for the site. I need some advise about my newly bought 1970 f100 auto, 360, ps w 91k miles. I've owned this truck for about a month and drove it from Reno about two and a half hours home with no trouble at all. Everything works, all but the fuel gauge sending unit that I've already replaced and is now working I've driven it around town, again no problem.
Last weekend I drove it to my first long trip, 2 hours on mostly flat highway, no problem. I stopped for refueling after a half a tank and before the rolling hills towards the lake. I drove about 20 more miles and the engine sputtered and died. No tools, no light and a two lane highway, Saturday night on a holiday weekend. I smelled no fuel at the carb, so I primed it by unscrewing the filter canister from the bottom of the mechancal fuel pumpand pourind a bit in the carb. It started right away, idled well and while in park, sounded ready to go. When I dropped it in gear, it took all the gas pedal pumping to keep it running. I got a couple more miles down the road, each time re-priming the carb. after a mile or so. I ended towing the truck to my buddy's house at the lake. After chasing down a new fuel pump, the truck started a ran great. I test drove it at the lake and seemed ready for the long drive home. I had about a half a tank of fuel and after driving about 10 miles toward home, the truck again died the same way. A CHP sargent stopped, he owns a 68, he got right under the hood, checked the points, He thought the coil needed to be replaced. I already replaced the coil when I replaced the fuel pump. We saw fuel spraying in the carb, so I tried it, it started and ran. I kept the fuel cap off thinking vapor lock issues. I waved off further help and, sure enough, 2 miles later, engine spudered and died. (repeated two more times), Finally, it would not start and the battery was running down from cranking. I began walking into town, buying a two gallons of gas, truck started ran. I had about a quarter tank of gas at the time. I topped off the tank at the station, got on the main Freeway, ran 2 hours and 100 miles home just fine.

What the heck is going on? Before I bought the truck, it sat for at least a year. there was a reciept in the glove box from the previous owner that the carb was rebuilt 5000 miles ago. The truck is complete and in good shape otherwise. I was thinking fuel pick-up line? Crap in the tank? Bad new fuel pump? help

[drytoast]

Sounds like something was in the fuel line starving it from fuel and finally made its was through. That would be my guess. BTW welcome to the site.

[flyboy2610]

You may have had something floating around in the tank plugging the fuel pickup tube.

[NM5K]

Sounds like the dreaded rust rocks..
I've had the same exact problem from time to time.
I'd almost be willing to bet you have rust in your gas tank.
When you filled up with gas, you gave the tank walls a wash
job, and the rust particles fall to the bottom of the tank and
either clog the pickup tube at the bottom, or go through the
line and get stuck in bends, and then clog the line.
I've had to pull and clean my tank twice. The last time was
about a year ago. I took it to a shop to see about getting it
coated or rebuilt, and they quoted such a high price I declined.
I could buy a new tank for not much more.
So I took it back home and gave it a good cleaning and stuck it
back in.
One thing I recommend for rusty cab tanks. Install a filter right
after the drop tube from the tank which meets the rubber tube which
connects to the main fuel line. Where that rubber short piece is,
stick a filter there. That will keep your line from getting
clogged. Just remember the filter is there, as it may clog up if the
tank is real rusty. I had that happen once, and forgot about the
filter and wasted a lot of time trying to find the clog until I remembered
the filter under the cab. Changed it out, and vroooomm!
I haven't had any trouble since that last go around..

[fordman]

it could be something in the tank floating around and getting sucked up. it could also be vapor lock still the fuel line between the carb and fuel pump needs to have a piece of rubber hose in it and not all one piece steel.

[TheEskimo]

I had a problem with crud in the tank when I got the '72, caused simmilar problems like has been stated by others. Haven't had any problems since I cleaned out the tank. Wasn't any rust, but the truck had sat for years on an orchard without a gas cap and we found everything from rocks to gum wrappers and sticks in there.

[george worley]

Clean tank put inline see thru filter close to tank. Check condition of filter often. If the filter turns rusty color you have rust in tank.

[fordwannabe]

Empty tank of gas, remove tank, place a foot long peice of new chain in the tank grab a buddy and shake the wee out of it, upside down -back and forth around and around, flush the tank with clean new gas(only a little) dump(gas and chain) and reinstall tank. You won't believe the ,,,uhmm...stuff you will get out of tank. Good luck. Tom

[alpinefr3ak]

Sounds like the dreaded rust rocks..
I've had the same exact problem from time to time.
I'd almost be willing to bet you have rust in your gas tank.
When you filled up with gas, you gave the tank walls a wash
job, and the rust particles fall to the bottom of the tank and
either clog the pickup tube at the bottom, or go through the
line and get stuck in bends, and then clog the line.
I've had to pull and clean my tank twice. The last time was
about a year ago. I took it to a shop to see about getting it
coated or rebuilt, and they quoted such a high price I declined.
I could buy a new tank for not much more.
So I took it back home and gave it a good cleaning and stuck it
back in.
One thing I recommend for rusty cab tanks. Install a filter right
after the drop tube from the tank which meets the rubber tube which
connects to the main fuel line. Where that rubber short piece is,
stick a filter there. That will keep your line from getting
clogged. Just remember the filter is there, as it may clog up if the
tank is real rusty. I had that happen once, and forgot about the
filter and wasted a lot of time trying to find the clog until I remembered
the filter under the cab. Changed it out, and vroooomm!
I haven't had any trouble since that last go around..

You can buy a gas tank repair kit at Napa for about $45 that comes with 3 things to clean and protect the inside of the tank. I think it was a solvent, cleaner, and sealer. Something like that. Anyway it supposedly works well to fix old truck gas tanks. I'm going to get one to use on my tank once I get it out.

[NM5K]

Yep, I've seen those sealer kits.. Probably should do that before it gets much worse.
The way I cleaned mine is I get a can of engine cleaner. Gunk, or whatever it was.
I pour that in the tank, and then I go raid a bucket for a few hand fulls of bolts, nuts,
etc.. Throw them in the tank. You can roll all the stuff around in the tank and it
will help dislodge some of the rust and crud. I also have a long handle brush that
I can use to get some of the sides of the tank. I'll swish it all around and let it sit
a while. Then swish some more until I think I got most of it.
Then I dump the now nasty red looking engine cleaner and all the bolts.
Then I wash the tank a few times with warm soapy water to get the slime out.
Then I sit the tank upside down so it can drain and dry out.
After all that, it will be clean enough for gov work.
Once you have a fairly clean tank, the easiest way to keep the rust down is
to keep the tank full of gas. Course, I don't always follow this advise..
So far I haven't had any trouble since the last time I cleaned it.
When I first got the truck I had to clean the tank, but that was as much to get
rid of old varnish as it was rust. The last time was purely rust dust and rocks.

[Johnm]

i know i had gas go bad in the lines of a truck i bought. this doesnt sound like the problme since you put a bunch of new gas in it, but this is kinda what happened to me, new fuel lines were the fix for me and sure enough there was gunk in the lines that was breaking loose and clogging everything up.