Packard Forum Index » Pre-War (1899-1942)

The 34 Eight fuel line from the tank forward doesn't make many sharp bends as there are brass 90 degree elbows riveted into the frame to make the the right angle turn forward at the rear, and inward towards the pump at the front. Thus the sections of the line are relatively straight.

The heat shield on the EE-22 carburetor shields the fuel bowl from the heat of the manifold; whether it's absence is causing you a problem or not, you should try to find one or borrow one to make a replica. My 34 has been in all kinds of hot, strenuous situations over the years and never had a fuel vapor lock problem, even with today's 10% EtOH gasoline. No electric pump, the mechanical pump is on the non-manifold side of the engine and gets pretty direct cooling from the fan blast.

Sorry, I did forget to crawl under my 34 and see where the fuel line exits the tank, but I'll do it today and respond.

EDIT - fuel line exits the tank at the top center, if memory serves the diptube is intergral with the sending unit. If the diptube has gotton porous it will certainly cause aerated fuel supply as long as the fuel level is below the perforations.

I don't think there is any value to the suggestion of adding a one-way valve, you already have that in your mechanical pump and if that one is not functioning satisfactorily, you should service the mechanical pump.

The tank is easy to drop. No other way to get to the sender/pickup tube. 3 bolts and the neck, down she goes. There's even a drain but you're better off using up whats in it as much as possible.

The heat shield goes on the outside of the carb toward the ex manifold. Most are missing. Check for kinks, shoddy reworks from the past, a clogged additional fuel filter. The fuel pump and sediment bowl has it's own screen for easy cleaning. I've not seen vapor lock in over 10 years. Sometimes "as-is/was" is the best solution. Ask yourselves why there seems to be more Packards of this era still around.

Hi,

There seems to be a few threads on about the same problem.

There is no heat shield but will make one, from my experiments with heat reflective foil tape, it seems heat is the cause of the problem.

Thanks for your advice.

Pat.

I guess what is happening here is that you park the car and then it won't start.(?)

You can test for leaks in the fuel pump by plugging the input and applying vacuum to the output (fuel line at caburetor). Next check pump pressure and flow (2 pints per minute). Make sure the heat control valve isn't stuck closed. Check your ignition for 20,000 volts with motor running. Rough idle? Check your idle and cranking vacuum (2-5 in hg) and if it is low block off the power brakes and wipers and retest. Still low, check the anti-flood and manifold for leaks. Still low, check the compression.

Is gas running onto the ground from the anti-flood?

Then most likely culprit is plugged air bleeders in the main jet. This requires some professional service from experienced personnel to avoid breaking the carburetor into little pieces.

Packard was apparently having problems because they were putting heat shields all over those cars and releasing service letters blaming the malady on vapor lock in the gas tank.