Topic: Evaporating gas on my 49 ford flathead V8.


Rudys36    -- 06-09-2021 @ 5:08 PM
  Hey Guys,
I just wanted to know if there is a cure for this new gas that turns into vapor at higher temperatures. I Just installed a new mechanical fuel pump, I have no problem starting it, but once I am on the road and especially going up a grade it coughs like fuel starvation. Should I put a inline electrical fuel pump, or a spacer between the intake manifold and carburetor?


sarahcecelia    -- 06-09-2021 @ 5:38 PM
  If by "new gas" you mean that ethanol cr*p, ethanol is ALCOHOL, and alcohol will evaporate while you are looking at it!! It evaporates like laquer thinner!! Put some on you from your medicine cabinet; it evapoates instantly!!

Regards, Steve Lee


nelsb01    -- 06-09-2021 @ 5:59 PM
  While others use it, ethanol can cause problems in older vehicles.

When I travel I always check with https://www.pure-gas.org to find gas stations that still have non-oxgenated gas.

If it coughs under load, then you may have another issue.



carcrazy    -- 06-09-2021 @ 7:56 PM
  Your engine is probably suffering from a fuel starvation problem when it is under load and the demand for fuel is increased. Check the fuel delivery system for the cause of this problem. The flexible hose that connects the fuel pump to the hard fuel line on the firewall may be failing. It could have a vacuum leak that while not actually visually leaking gasoline, reduces the flow of fuel to the engine. Make sure that all of the fuel line connections between the carburetor and the fuel tank are sealing tightly and are free of leaks. Check the seal at the top of the fuel pump sediment bowl to make sure it is tight and sealing properly.


Rudys36    -- 06-09-2021 @ 7:58 PM
  What could cause her to buck while I am under load. I have a 1949 Flatty V8. Runs okay only when I hit a slight incline at about 40 mph she starts to buck.


FordFreak    -- 06-10-2021 @ 6:11 AM
  Somehow it is starving for fuel , or your distributor may have turned, and retarded the timing.

1937 Ford Coupe
1952 Ford F1 Pickup
1965 Falcon Sprint


TomO    -- 06-10-2021 @ 7:51 AM
  Electrical fuel pumps cause more problems than they fix. The spacer is a solution looking for a problem.

First, I would pull out the choke slowly when this happens. If performance increases, the problem is fuel delivery.
For fuel delivery problems, I would check the float level, next I would do a fuel delivery test. Fuel delivery can be impaired by a vacuum leak on the input side of the carburetor, a plugged or deteriorated flexible line or a bad line from the tank. If the fuel delivery test checks out, send your carburetor to Charley Schwendler in NY for a rebuild.

If there was no change,when you pulled out the choke, check for proper distributor advance operation.

Here is a link to a topic with the fuel delivery test procedure:

https://www.earlyfordv8.org/forum/viewmessages.cfm?Forum=14&Topic=14694&keywords=fuel%20delivery





Tom


Rudys36    -- 06-10-2021 @ 10:56 AM
  Thanks for the heads up guys, I am going to try driving it today and hit the slight hill and pull the choke slowly, that should let me know if it stops bucking or not. Ill let you know what happens. Thanks for that last tip Tom.

Rudy


Rudys36    -- 06-11-2021 @ 11:34 AM
  Hey Guys.
I checked the 1/4" line from the distributor to the intake part of the carburetor and it looked okay, but I tightened that connection to the carburetor, which was slightly loose and tightened it. I took it out for a drive and drove it uphill and accelerated to 50 mph and it did not buck. I hope that simple task of tightening the line to the carb did the trick. I will still keep on eye on it, I may have to replace that line if it keeps doing it. Thank for your tips guys. I would also like to thank Tom for that last tip. Happy cruising guys.

Rudy


nelsb01    -- 06-11-2021 @ 1:25 PM
  As much as we need air to breath --- a fuel line does not.

Your tightening may have fixed your problem.



TomO    -- 06-11-2021 @ 7:16 PM
  That line is for the vacuum advance of the spark. being loose would affect the spark advance and could very well be the source of your problem.

Tom


supereal    -- 06-26-2021 @ 9:00 AM
  Loss of fuel from the carb bowl can often be due to leakage around the power valve when a triangular seal washer is used. These often come in repair kits, and if tightened too far will allow fuel to drip into the intake manifold where it can't be seen. This can cause hard starting, and insufficient fuel in high demand situations.


EFV-8 Club Forum : https://www.earlyfordv8.org/forum
Topic: https://www.earlyfordv8.org/forum/viewmessages.cfm?Forum=18&Topic=14903