i cant keep my small block 289 running. i slowly lose fuel pressure and after about 45 minutes at idle or 15 minutes on the road the fuel pressure goes from about 7 1/2 to 0 and the truck just stops running. i have a inline fuel guage so i am able to keep a good eye on it and can tell when i am going to stall. ...the carb has just been rebuilt and the fuel pump and filter is new. it really "seems" like vapor lock but, it starts to lose pressure when the fuel line just starts to get real warm but not hot..

i was wondering because this is a high mileage engine and i get oil into about 6 of the sparkplugs that maybe the engine just cant run any more? i dont know what its like when an engine just says "nope i dont have anything left" ive never had this happen before?

what else could i do with the fuel system? i dont want to replace the engine yet if its still has some life in it. it starts first turn EVERY time.

any help is greatly appreciated..

thanks, very frustrated RC

 

Is the fuel cap venting or will it keep running if you left it off?

 

[updated:LAST EDITED ON 08-Oct-02 AT 00:19 AM (EST)]RC, I recently went through the fuel tank and fuel line on my 54 F100. The symptoms I was having were very similar to yours. What I found was that the rubber hose that connects the gas fill tube to the tank had rotted and the rotten bits were getting into the fuel line and jambing the line shut. The truck would start and idle and drive a little, but it would start to sputter and stall if I drove it much. Luckily, I have a carburetor with a glass float bowl; I could see the fuel pump laboring to keep it filled.

I have pulled the fuel line completely out, blew compressed air through it until it flowed well, and reinstalled it. I have replaced the rubber hose and washed the fuel tank out. Problem solved.

The previous owner of the truck evidently had experienced this problem. He had replaced the fuel pump and gas filter.

Good luck,

 

i have tried running it with the gas cap off but it does the same thing. i guess my next step is blowing out the lines but if that doesnt work is the next step after that having the tank cleaned out in some way???

thanks 57 ford and pcmenten for your help...

RC

 

I second the above advice. I had the exact same symptoms with my '67 recently after bringing it back to life after an extended storage. I pulled the tank out and found that there was so much garbage and rust in it that it was plugging the pickup tube. Pull your tank and clean it out and I'll bet your troubles will disappear.

 

thanks for the help guys. this weekend first, i will blow out the lines and if that doesnt work i will drain, pull and then get it cleaned.....

RC

 

i just thought of one more thing...with the truck running of a 12 volt system now, if the sending unit was only 6 could this be a problem also?? i dont know what is in there now but if i have to take the tank out i will change it if i should???

RC

 

OK. last weekend i tried to blow air through the lines and at first it would not go through very well. after a few tries there was a release somewhere and the air started going through into the tank pretty easily. so i started it up and was getting just over 8 psi for the first 10 minutes but then it slowly started getting less and less pressure and after about 25 minutes there was less than 1 pound.??????

i once read here the tank has a master shut off switch on it. if that is true could it be i have it turned part way closed?? or do i need to take the tank somewhere to have it cleaned?? or what ?????

i am really lost now and dont know where to go from here...

thanks for any ideas .....

frustrated RC

 

also. i forgot to say i drained and then flushed the tank with water 2 times and then re-installed it hooked up the lines and then started here up...

..RC

 

Hmmmm. What exactly did you do to the tank while you had it out? If it has a lot of rust in it, it will keep flaking free and contaminating the fuel if all you did was rinse it. Then as you run the engine, the fuel flow towards the pickup pulls all the debris along with it until it covers or plugs the opening. The best way I've found to clean one out good that has rust in it is to empty it and leave it in the sun for a few hours until it is dries out good. Then dump about a cup of 1/4-20 nuts or some washers or small bolts or whatever you've got a bunch of in it and shake it around. A lot. Turn it every conceivable direction and shake it up. Then do it some more. And a little more after that. Then dump all your bolts/nuts/whatever out. Pour about a gallon of gas in it and slosh it around. Pour it into a bucket straining it through a couple blue paper shop towels. Using the same gas, rinse it again and strain it again. Repeat until the gas doesn't leave rust or dirt on the towels anymore. At this point, you've probably got it clean enough to not cause any more trouble. CHANGE THE FILTER and put it back in. If you changed the filter before you cleaned out the tank, it's probably sucked full of junk again and may be causing your problem now.

 

I would also go ahead and purchase a kit with cleaner and sealer and seal the tank while you have it off, replace all flexible hoses, filters etc.

 

[updated:LAST EDITED ON 22-Oct-02 AT 07:19 AM (EST)]Sounds to me that your fuel line is plugging up again. No, there is no master shut-off switch.

When I pulled my tank, I removed the fuel gauge sender from the tank. I could easily see into the middle secton of the tank with a flashlight. What I saw was a layer of varnish and some of the rubber bits. The fuel line does not have any sort of screen or filter on its end so it would be easy for it to suck up debris.

I would blow more air through from the fuel pump side. Then I'd try to pour some caustic solution into the line. Dissolve some drain cleaner, like Red Devil lye, in water and pour it into the fuel line and let it run out into the gas tank and out the drain. It's nasty stuff (read the label) to handle so you'll have to be creative about getting it into the fuel line but that should dissolve the varnish that's helping to gum up your fuel line. Flush with water.

 

first i drained all the gas then i filled it with water and then emptied it out, filled it up again and let it sit for a couple of days and then emptied it out and put the tank back in the truck. i put about 3 gallons in it and it started up on the first turn.

thanks for all your answers guys but, what is the BEST way to clean this out. take it to a mechanic or a radiator shop?? i dont care if i have to spend $100.00 or more i just dont ever want to have to worry about this again..

thanks, RC

 

If you can find an Old Tyme Radiator Shop that actually works on radiators, not just sells new ones, yes, they can clean it out. I cleaned mine out by filling it with water and lye. I had no rust or scale, just dirt, varnish, and rubber bits from the rotting hose that connects the fill tube to the tank. My tank came out clean as a whistle with lye.

But I think that you've got stuff jambed into the fuel line. I think you need to clear that out.

 

well the steel/copper fuel line that goes from the pump to the tank was letting the air i was blowing through it go through with no problem.. then i just put a brand new hose to connect it to the tank, so i really think my lines are clear...

i will try blowing everything out one more time and if that doesnt work i think i will take the tank to a radiator shop. there is one by my house that has been there forever..

thanks,, rc