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

Hollanders will tell you if the interchange satisfactorily. If you spend much time with older cars, Hollander's should be a near-essential. Also, PI published an Interchange manual which may be out of print but I have a copy - I'll check later and advise.

But I'd need to know which 50 and which 53 model (engine) the pumps came from.

EDIT: Just checked PI's version of Hollanders. A 1950 fuel pump regardless of engine application does not functionally interchange with any 51-54 fuel pump.

Well there's that. I'll check with MM tomorrow to see if i can get an exchange.

For future reader reference the engine was a 50 288 solid lifter, the new motor is a 53 327 9 main hyd lifter.

I'll ask if the 53 is still double action for the vacuum wipers.

Yes, 1953 is a double action pump.

They do interchange physically, but are not listed as interchange because the plumbing was done differently. I am running a 47 pump on my roadster with 51 engine as I did not want the vacuum pump. The basic operating arm and mounting is all the same.

So maybe not the culprit then...unless this just happens to be a bad one or have an issue with it.

GAS CAN IN PASSENGER COMPARTMENT- DANGER

During the '73 gas crisis most states passed laws forbidding gas cans in the passenger compartment for good reason. If a car gets hit the gas may get sloshed all over the inside or if it tips over it may spill. A fire extinguisher will put out a fire, but gasoline is not a regular fire like paper or wood. Often the ignition of gasoline/ gas vapors is an explosion which produces virtually a liquid flame which spreads with ferocity.

If you are driving a car and a gas fire starts the last thing you have the ability to do is drive and operate a fire extinguisher, besides the crises happens in a split second with disastrous results.

There is a reason that temporary fuel tanks are not available in Pep Boys, etc. Laws/Danger/Liability.

For every reason I would strongly caution you on using an in-the-car fuel supply.

Common sense warned as much, but, as usual in these situations, the quickest way to determine something was the riskiest. Fortunately the test went off without a hitch and showed that the pump is for some reason getting lazy shortly after being started, and goes back to normal after cooling down. I still haven't had a chance to call to check about exchange.

Also, saw summit (hour from me) has the airtex pump in stock, i'm thinking of rigging an electrical pump in line and when it looses pressure, turning it on and seeing if the spark knock goes away. Electric pump is $50 vs $125 plus $125 core of replacement mechanical. Wouldn't want to run it normally as my pump seems pretty cool when it's not pumping, but it'd be nice to get a determination.

Has anyone else monitored their fuel pressure? Maybe it's normal to have a drop in fuel pressure after warm and i'm barking up the wrong tree? I can't imagine that's the case, but i've been wrong plenty before.

Other than something that might be clogging the screens in the pump bottom section which falls away during down time and then gets sucked back up after a few minutes running, can't think of anything else in the pump other a valve which might be expanding or deforming with heat causing the drop. You did change the flex hose???--another source of intermittent loss of flow after a few minutes.

I did put a new flex hose on, and when running the clear line from the gas can to the pump i connected it to the pump directly to bypass all incoming fuel lines on the car.

The thing about the heat is that it happens so soon that the pump can't be more than 70-80 degrees, maybe 100. The fuel bowl at the bottom (the metal one on the bottom of the pump) is actually cool to the touch. I don't know if temp is the trigger, or if time pumping is the trigger.

If it was debris, i would also think that shutting the car off and letting it sit for a few minutes would allow it to build pressure again. Usually have to let the car sit for quite awhile.