Fuel shortage

[Ford coupe]

My 55 272 seems to be running shy on fuel when I get it up to about 50 mph..Starts great runs great but when I drive it at 50 it seems to be starving for fuel and wants to cut out and stop until I put on the electric back up for 10 15 seconds and that seems to give it some extra fuel and is ok for a bit..So I feel it is not drawing enough fuel through the back up fuel pump and therefore starving for fuel...Is it possible to put a bypass line at the electric pump with maybe a couple Ysin the line???If so would that hinder the electic pump when using it to start the car after sitting for a longer period..

[dmsfrr]

How old is the stock fuel pump? It could be on the way out and/or have leaky check valves.
Check the fuel pump output pressure if you have a gauge.
If the fuel where you are has ethanol in it, it may have damaged the pump.

[scicala]

Good advice from Dmsfrr.

Sal

[dmsfrr]

Originally Posted by Ford coupe

...until I put on the electric back up for 10 15 seconds ...

...Is it possible to put a bypass line at the electric pump with maybe a couple Ysin the line???If so would that hinder the electic pump when using it to start the car after sitting for a longer period...

If there's a bypass line around the backup electric fuel pump and you turn it on, the fuel coming out will take the path of least resistance and virtually all of it will go back to the elect pump's inlet side.

When the engine is 'starving' for fuel, does it run well if you just leave the elect pump on?

.

[Ford coupe]

Ok pump was rebuilt a year ago and I don't feel it is that but could be wrong..now it goes along well for maybe 5 10 minutes and if I get it up to say 50 mph it will start hanging back for a bit and then goes to stop so I turn on the electric pump and within 5 or 10 secs it comes back to normal for maybe 5to 10 minutes.. I felt that a bypass would do just as stated just push the gas back to tank..Maybe I should just bypass the electric altogether and see what happens...Thanks guys...Harry

[50fordcoupeman]

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I would think by pass the mechanical and that would answer the question if it is bad. I am assuming you have checked/changed the fuel filter. Good luck!!

[dmsfrr]

A stock style mechanical pump in good shape usually has no trouble pulling fuel thru an elect pump, depending of course on the internals of the elect pump. If the setup you have was working well for several months or more and only recently started giving you trouble, I'm leaning more toward it being a tired mechanical fuel pump.
If there's a recent obstruction in the fuel lines chances are it would affect the elect pump as well, so that's almost ruled out. There could be a slight chance you're getting a sediment buildup at the inlet to the electric pump (it's closer to the tank?) and operating the pump relieves the blockage. And you'd be seeing/finding debris in the fuel filter.

.

[Ford coupe]

Ok it is possible the little filter before the pump may be plugging up will check..By the way the electric is a carter from macs..THNKS

[50fordcoupeman]

I had a similar problem on my '50. I installed a filter between the tank and electric pump. I also put a shut off valve on the line so I don't have to fight gas coming out of tank when I change the filter. Works great and problem solved.

[dmsfrr]

Originally Posted by 50fordcoupeman

... I also put a shut off valve on the line so I don't have to fight gas coming out of tank when I change the filter. Works great and problem solved.

Maybe some of us like gasoline running down our arm and soaking our shirt

Ford coupe
Just remembered.... there was another semi-recent post here somewhere about starving for fuel at increased speeds. He found a section of fuel line inside an insulating sleeve was mostly crushed, but hidden by the sleeve.

.

[Ford coupe]

Yes I have read about flex lines collapsing..Wow which direction do I go lol..

[dmsfrr]

Older rubber flex lines can do that, but this was a section of steel fuel line that was crushed.

When replacing rubber fuel lines use Fuel Injection rated hose, it's stronger and can handle ethanol better.

*edit* I found the original post and copied this photo from it.
I'm guessing it was near the steering box, with insulation for also being near the driver's side exhaust.
.

[Daves55Sedan]

All I can tell ya is that I had same problem with my '55 with 272 and Ford EBU carb years ago. On the highway at around 55 MPH it would starve for fuel.
Rebuilt the carb and checked float setting but it was okay. Still starved at hiway speed. Checked fuel pump and found it was pumping gas into crankcase. Replaced pump, changed the oil and it was okay ever after that.

[willowbilly3]

On any suspected fuel delivery issue, I use a hand held vacuum pump and a catch jar at the fuel pump, on the line coming from the tank. If you have poor return or bubbles, the fuel pump can't suck fuel properly.

[Ford coupe]

I cleaned the carb a couple wks ago and found a leaking power valve and replaced it with a new one out of another carb I had so as it was quite old could it have sprung a leak as age is no good for neoprene.Would a leaking power valve do this?? Car ran and started as never before after the cleaning but now this and of course it done this before the carb cleaning...So maybe need a power valve???

[scicala]

Even if the replacement power valve was leaking, that's not your problem of losing power at 55 MPH.

Sal

[TedEaton]

My '54 Ford Victoria had a crack at the flair on the steel line coming from the tank at the front where the flexible line for the inlet of the fuel pump connected. It was sucking just enough air to cause the engine to starve when at speed but the engine started and idled just fine. I simply cut off the offending end of the line and replaced with a rubber hose going to the fuel pump and that solved that problem. It did take awhile to find that crack though. Ted Eaton.