Topic: 1940 Ford with 85 HP with fuel issues


Gene's40    -- 05-11-2024 @ 11:25 AM
  I recently purchased a fully restored 40 Coupe 85 HP. The first time out for a short drive it acted like it was not getting fuel. The previous owner installed an electric fuel pump. This is my first early Ford V8 to own. Any hints on what to check first ?


1931 Flamingo    -- 05-11-2024 @ 12:06 PM
  Condenser?
Paul in CT


carcrazy    -- 05-11-2024 @ 3:20 PM
  It is hard to accurately diagnose engine running problems from a distance.

Does the engine run alright when first started and then begin acting up once it heats up, after about 10 to 15 minutes of run time? If so, the coil may be failing.

Another item to check is fuel pressure - Ford and Holley 94s like to have low fuel pressure, about 1 1/2 to 3 PSI. Many electric pumps put out more pressure than this which overwhelms the fuel handling system of the carburetor. Are the lines and hoses going from the tank to the pump in good shape with no leaks? Leaks on the inlet side of the pump may not visibly leak fuel but they can leak air into the fuel flow causing a lean mixture.




TomO    -- 05-13-2024 @ 2:48 PM
  First check your spark at idle, it should be blue in color and at least 1/4" long when the plug wire is held close to a head nut. If the spark is orange or yellow, you have an ignition problem. This could be a bad coil, bad condenser or worn ignition points.

If your spark passes the test, try driving it again. When it feels like it is not getting enough fuel, pull the choke out slowly to see if performance improves. If it does improve, your fuel pump is not delivering enough fuel. This could be caused by vacuum leaks in the fuel line (check all connections for tightness, check the flex line going to the fuel pump for cracks or bad crimps), clogged fuel line (check the flex line going to the fuel pump and the line going to the tank by blowing through them with low pressure air supply). The fuel pump could also be worn.

See https://www.earlyfordv8.org/forum/viewmessages.cfm?Forum=18&Topic=16439&keywords=fuel%20delivery
for more information.

Also I would get rid of the electric fuel pump and put in a solid steel line from the tank to the firewall location.

Tom

This message was edited by TomO on 5-13-24 @ 2:50 PM


Gene's40    -- 05-14-2024 @ 11:35 AM
  Thanks Paul

Gene Talley


kubes40    -- 05-15-2024 @ 1:57 PM
  Hi ya Gene. I'd pay careful attention to TomO's advice. He is about as sharp a guy as you are likely to find.

Mike "Kube" Kubarth


sarahcecelia    -- 05-28-2024 @ 12:14 PM
  If there is an on/off switch; usually installed along the frame in front of the front of driver side rear wheel; or some other place; on the lip of the dash on driver side;at the fuel line from the gas tank to the motor where it is -it must be always be "ON" when the motor is running!! I know; I installed one on my '40 and when driving home from a show it started to act like it was starving for fuel and quit 2 times. The I realized it was the on /off switch that was OFF; for the electric fuel pump!Turned it on ;started the motor, and drove HOME!!

Regards, Steve Lee

This message was edited by sarahcecelia on 5-28-24 @ 12:15 PM


Carcheologist    -- 05-29-2024 @ 6:56 AM
  A friend of mine was having the same problem with his '40 pickup - would start and run for a distance and then die; he couldn't trust it to get him home. Sometimes after driving for a while, it would not restart once he turned the engine off.

After installing a new carburetor, condenser, points, fuel filter, etc. he decided to check the flex hose attached to the fuel pump. The hose looked pretty sound, but he wasn't sure of its age. He removed the hose, plugged one end of it and immersed it in a bowl of water and used his air blow gun in the other end. It bubbled almost half the length of the hose!! It was sucking more air that fuel causing fuel starvation. New hose installed and problem went away.


sarahcecelia    -- 05-31-2024 @ 6:56 AM
  If the electric fuel pump is turned OFF; the motor will starve for fuel!That has to be on anytime the motor is running!! I had one on my 1940; and I learned thatlesson one time; then I ALWAYS left it in the "ON" position!! PROBLEM SOLVED!!!!

Regards, Steve Lee


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