Packard Forum Index » General

Having been a car collector for 57 years and owned 500+ cars I've wondered why all the talk about needing an electric pump on cars that performed without one for the first 50+ years of their life. We have one with an electric, a 1930, that we purchased with one. It often sits for a year or two and we use it to fill the vacuum tank.

I read about needing an electric to fill the carb after sitting a few weeks to much longer. We just got in our shop a 48 custom convertible with 23,000 miles virtually original mechanically. It was difficult to start, cranked quite a bit, started a bit then quit. The choke was not completely closed so I rotated the choke cover two marks and it sprang to life and ran at 2000 rpm.

Fast idle screw was all the way in explaining the high rpm.
Other adjustments were way off too so we decided to remove the carb, disassemble and inspect and set it up according to the Carter spec sheets. An hour later it was starting very well after few cranks to fill the bowl, ran fine after mixture screws were dialed in. Has a miss that can either be an old spark plug problem or a valve problem, to be tackled this week.

To determine the advisability/need for an electric I took the top off the carb, emptied the bowl, drained the pump to carb line. Put a can at the top end of the carb to pump line, cranked the engine; it took 3 revolutions of this slow cranking (gear reduced) starter to get enough fuel to mostly fill the bowl.

Poured it in the bowl,put top/float on and screwed it down. The car started on the first short try and ran well.

If a fuel bowl evaporates completely and the fuel in the pump to carb line does also then it only takes 3 revolutions of the engine to being fuel to the carb bowl, hardly enough to "burn out" a starter. We sell starters for all makes and models and get cores back, have yet to see a "burned out " one.
Worn brushes. worn commutator, dead spot on commutator yes. Very seldom bad fields. I've cranked and cranked some cars and never had a starter fail.

The cause of long cranking on the 48 Custom was an incorrect choke setting, had similar trouble with a 52 Patrician (hot), not vapor lock but a disconnected accel pump.

I would look elsewhere to cure hard starting/hot starting before installing a "band aid "electric pump. My summer car, a 66 Eldorado has a hard starting problem, cause is a sticky choke that I have to fix.

Fred, for the most part I agree with you but there are exceptions. With my '56 Caribbean with dual Rochesters rebuilt by Daytona and in perfect operating order, if the car sits more than 15 or 20 days, it's an HONEST 20 seconds worth of cranking to get sufficient gas into both bowls to start the engine. Fuel pump pressure and delivery are up to snuff. So finally, after 20 years of listening to my starter cranking away, I now use an electric to prime the dual carbs.

On the '34, it can sit for months and will probably start on the 2nd revolution without any assist from an electric pump.

I have driven my 55 Clipper Custom almost 70,000 miles in 10 years. The only time I use my electric fuel pump is during the summer time when it is over 100'F and I'm going faster than 55mph. My car acts like it is running out of gas until I switch on my electric fuel pump and then everything smooths out, even when I'm doing 75mph (that's the speed in Phoenix, AZ). I still drive to car cruises during the summer and I will still use my electric fuel pump when it's hot. In the winter here, I don't use the electric fuel pump.

My 40 160 Touring sedan has an electric fuel pump for the same reason, except it needs it when I hit 50 mph (I don't do 75 mph with my 40 160, no overdrive).

My 53 Patrician acts like it is running out of gas as well, until I turn on the electric fuel pump.

I crank the engine until it fires. I know there is no fuel in the carburetor.

I don't know if it's the gas here in Phoenix or LA, but I will use my electric fuel pumps when it's hot here (or there).

That's why I use an electric fuel pump. (Maybe it's me.)

Most interesting, perhaps it's the high temperatures there. I'd like to know if other cars of your vintage, such as gather at Walmart or Wendy's cruise-ins have the same problem. Could you ask around??

Do all your cars have a proper vented gas cap, lack thereof would cause this problem. There was an article in a Rolls publication on long term driving in high temperatures leading to increasingly elevated tank temperatures and fuel delivery problems.

Disregarding all other factors, Gasoline has definitely changed over the last 60 years & this alone is a major culprit.
With the vapor lock issues that I have had, I have new appreciation for all the louvered hoods on the traditional Hot Rods. No wonder this trend started in SoCal. They knew their stuff.

Louvered hoods started in the late 40's as I have observed, long before the "new" fuels. The may have been functional but they surely were and are cool looking if not cooling

The 48 custom 8 sat over the weekend unused. To see if I could improve starting and in initial running I closed the choke one more notch. It started on the second revolution and fast idled flawlessly.

Next I MAY try heating up the fuel line under the car with a heat gun to simulate Arizona ambient temperature plus. then try starting the car to see if I can replicate vapor lock. Perhaps I'll put it in our paint booth and turn the temp up??

LATER NOTE: Our paint booth goes up to 140 degrees. Once I have driven the car and am sure it starts well under all normal road conditions I will put it in the paint booth at 105 degrees for a sufficient time to get the entire up to temp and check starting, restarting and fuel delivery and pressure.

a test or series of tests run on one car in NJ does little to make it a fact extant. I think you're beating that horse unnecessarily.....what's your point? is it: the only success is your success? Just curious. Now comes the broadside.

I am a scientist/engineer, as such when I see reports of "vapor lock" which I have never experienced in 57 years I want to see if I can replicate it. I have experienced situations where it appears to be vapor lock but is not and all have been explained by mechanical defects.

There is much on the internet which I call mechanical hysteria where a person describes a phenomenon and many hop on board claiming the same. Case in point, the Bendix Treadle Vac phenomenon. Read about it for years, saw lots of cursing at the unit, then evaluated 5 failed units sent on by forum members. All 5 had suffered from neglect and many years of long term storage.

Since reporting on that there have been no more reports on the forum of failures. It was my feeling from my 50+ year experience with BTV's that it was not a design failure as was said but poor owner maintenance. It seems I have for the time being proven my theory.

My success is not proving I'm right, it's the safety of motorists that is the goal.

On the experiment with "vapor lock" I intend to identify the real problem. That way forum members can have safe and reliable cars and save money not having to buy clothes pins, a method suggested and tried by some members who claimed to cure vapor lock by putting them on their fuel line.

There is no broadside here or in other posts, just facts presented in a logical and professional manner for all to read, follow or question in a positive manner. I give things my best professional effort in order for fellow enthusiasts to enjoy safe trouble free driving.

Take it as you wish.

firstly I didn't have to even open this thread to know Fred started it LOL

secondly I have a 1970 Dodge Dart. New gas tank, new sending unit, new hard fuel line, new rubber lines, new fuel pump, new fuel filter, new carb, pretty much the entire fuel system from start to finish replaced.

car ran fine, it was summer. come winter it ran like crap. put a see through fuel filter on it, fuel was vapor locking and bubbling in the fuel filter.

couldn't figure out how to stop it from happening.

the only solution was either summer mix gas or putting race gas in with winter mix gas. car never acted up again. point is the winter mix around here has a very high volatility.

on to the Packard....car runs fine on any gas so far, but only around town. get on the highway above 50 and it will stumble...at which point I put on the electric pump and it stops stumbling. I don't leave the pump running. just to get the stumble to stop. car has new carb, new filter, new rubber lines, new fuel pump. blew out hard lines and they were clear.

lastly, I guess you didn't see BigKev's warning about the clothes pins. lol!

P.S. all of these theories/myths/rumors will still be around long after your gone Fred. Thanks for trying to figure out what you can, but honestly its a futile effort. people are going to believe what they want and continue to do what fixes the problem for them and move on with life.