Packard Forum Index » Post-War (1946-54)

PackardV8 Quote:

Heck, just leave the hood off if that fixes it. Besides, how "cool" would that be?

Craig

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Wow - where would I mount the hood ornament, maybe I could just mount it on the cowl? I could also use the hood as a sled when it finally snows here again, eh?

My 55 Clipper was vapor locking. After trying various things, I finally found that my gas line, by the rear tire where it crosses through the frame, had a pin hole in it. So my mechanical fuel pump on the engine was sucking air and the electric fuel pump near the gas tank was pushing gas out the pin hole. After replacing just a short line I have not had vapor lock since and I am still driving in Phoenix when it's 110F, of course not every day just on the weekend to a car show and it cools off to 100F for the ride home at 8pm. Keep on checking the fuel lines, you may have to get under it and look for somewhere wet.
Good luck.

Wow! All these cars having problems.

If there is a car having this problem that also has an electric pump, then how about bypassing the mechanical pump and running the motor via the electric pump?

Way back when I dealt with a high mileage 56 Exec that was having this problem and because it was just an old car we bypassed the fuel pump and ran it on electric. It was a cheap repair that satisfied the owner who just used it as a second car.

However, the root cause is still important. I am sure that these old blocks just don't run as cool as new which creates problems. The prewar cars have bigger radiators and so overheating can be reduced to a manageable level. But I had similar problems with a modern car that was high mileage and always running hot.

For somebody out there interested in an experiment, take a heat gun (or powerful hair drier) and aim it at the fuel line, carburetor, and fuel pump with the motor running. If it stalls then you have isolated a problem area. (I suppose a propane torch would also work! but only on the fuel line)

The insulation block idea is also valid as it concurs with the Packard company service letters which state that vapor locking results in the low pressure carburetor circuits.

Of course stuck heat risers will create big problems in hot weather as well.

I assume in each of these cases valid ignition has already been confirmed. Given today's cell phone infested highways, stalling is a huge safety problem.

I've since replaced an electric fuel pump on my '50 as well as replaced about 10' of metal fuel line with rubber line. There was a small leak in the metal line located just below and about in the middle of the drivers door. The electric pump is frame mounted and puts out 8 - 12 psi. I think that it is too much and have purchased an in-line fuel pressure regulator. What is the proper psi setting for my 288 ci engine? Any help would be greatly appreciated.

An electric pump that puts out 8-12 psi is a poor choice, especially as many pressure regulators have been reported to have poor reliability. You want a pressure of 3.5 to 4.5 psi, even 5 psi is probably OK.

Replacing undercar gas line with rubber isn't good practice. First, it's far more vulnerable to damage, perhaps leaking, from road debris, than steel. Secondly and probably a minor consideration, the rubber is actually an insulator and inhibits heat transfer from the fuel to the surrounding air flow.

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The rubber fuel line is a temporary fix until I can muster-up the bucks for fuel injection line. I was limited to the choice of 6v fuel pumps as this was the only one that I could easily find. Thanks for the proper pressure limit.

Forget all that, just get yourself the cheap and simple solution shown below!

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Details of the anti-vapor lock device. Best results are obtained when you use them in multiples of a dozen and arrange them in a spiral to get the full cyclonic windmill effect.

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Dear happ:

I know that method has been around for a long time, but why it shows up on older vehicles is a technical question.

Anyway, that gas line is too close to the manifold.

If I had a case like that I would carefully heat the gas line with a torch to see if the car stalls, then do the same with the clothes pins attached. Maybe those manifolds are eroding and transferring too much heat into the motor compartment. Given Packard's propensity for heat shield they apparently were able to produce such problems at the proving grounds.