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

Hello All,
Reference: 1938 Packard 8
Does anyone know of a supplier of fuel pump check valves for the double chamber fuel/ vacuum pump as fitted to a 1938 '8'.
The valves that I have are of the caged type 19mm in diameter.
The return springs feel very weak and the car looses power when climbing inclines, perhaps indicating fuel starvation.
Also does anyone have a good condition Stromberg EE-16 carburetor for sale.my car is fitted with the earlier EE-14,which was cobbled together from a number of pieces and has been a source of endless problems.
Regards,
Dennis Nielsen.

I apologize if I'm missing something in your query, but the valves are just standard parts of a pump rebuild kit. There are plenty of sources of kits, one that many of us have used and I can recommend is:

then-now-auto.com

Sorry, no help on the carburetor.

That carburetor is available on eBay. There are used and rebuilt ones. Kits also.

Have an Elect Pump installed INLINE? These will create fuel starving.

Quote:

I have been told this by more than one source and agree that 'pulling' fuel through a vaned electric pump would create restriction. Yet it seems MANY owners HAVE electric pumps as 'backup' or 'boosters'. How is this plumbed so as NOT to create issues for the diaphragm suction pump at the engine???

An electric fuel pump can be plumed in series or parallel. Most of us connect them in series and use a type of pump which does not restrict flow when pumped through. Forget if it is a rotary or vaned type. Other will be able to answer.

Thanks John. I bought an inline 6 volt fuel pump from NAPA and put it right at the fuel tank with an under-dash switch. Couple of presumptions... 1) that this is what you mean when you say 'in series'??? and 2) I thought all those little electric pumps were 'vane-type', am I wrong there??? And if my setup is considered in series, does 'parallel' involve 2 separate lines? If so, I don't understand how the engine pump wouldn't try sucking back through the electric pump where it re-joined the fuel line before the carb, kind of defeating the purpose. Or am I missing something essential here??

Pumps are either solenoid type or rotary type. Most rotary or vane pumps are the ones that have trouble allowing fuel to pass if the pump is off. Reason being that most rotaries have no valves so depending on where the rotor or vanes stop the passage is partially or completely blocked unless a special provision is made. Solenoid pumps work much the same way a mechanical pump functions with a diaphragm or piston pulsing and flow controlled by an inlet and outlet valve. Even if the solenoid is not pulsing the pump mechanism the mechanical pump can still pull fuel thru the valves which would just open and let fuel flow thru the pump chamber.

Most pick the solenoid pumps in spite of them being a bit noisier. To use a quiet rotary pump in series with the stock mechanical pump there generally needs to be a check valve with the flow direction toward the mechanical pump inserted in a short parallel line which would just tee into the fuel line a few inches in front and back of the rotary to bypass around the pump. If the pump is off, mechanical pump would pull and open the check valve so fuel flow would be thru the valve. When the pump is running the fuel would want to go both directions and short cut back to the pump inlet or tank but it would then push against the flow direction of the check valve. The valve would close and all the delivery would be in the only direction it could go -- to the mechanical pump.

Most use this arrangement so the electric pump can be switched on for priming or vapor lock conditions and be off for normal driving. One important requirement with this arrangement is the mechanical pump needs to be kept in good condition with a good diaphragm otherwise fuel could be sent into the crankcase which with the flow from an electric pump pushing could fill up quite rapidly.

Thanks for the info Howard. The 6-volt pump I have is quite noisy so I presume it is of the solenoid variety and from what you say, sounds like there is no issue drawing fuel through it from the tank to the engine pump. I am starting with a zero-hour rebuilt engine and wanting to do everything right, I purchased a rebuilt pump from Kanters. I am concerned about fuel bypassing the diaphragm under pressure from the electric pump (when it is on) and leaking into the crankcase, which could be disastrous. Is there any easy way to test or check the diaphragm in the 'new' pump to ensure it's integrity?? In trying to think this through, I thought another way would be running a double fuel line all the way from the electric pump at the tank and rejoining the fuel line AFTER the engine pump with a check valve, thus alleviating any unwanted pressure on the diaphragm. Does anybody do this, or am I trying to'reinvent the mousetrap'???

No way that I know of to tell if a rebuilt pump is in good condition other than trust that the rebuilder was competent and used fresh materials rather than old NOS kits.

As to the second line for the electric, yes that has been done and if you are not worried about authenticity is certainly a good safe way to go. Not sure if those who have done it used one, two or no check valves. Assuming the valves in the mechanical and electric are in good condition, if the tee connection is after the mechanical pump, in theory there would be no need for a check valve at all since either pump would be pushing against the flow the valves would permit in the other pump. Just be sure the electric pump is putting out a pressure approximately equal to that of the mechanical pump and you probably would not want to have both delivering fuel to the carb at the same time. Motors Manual gives two ranges for 39 pumps depending on engine. One is 3-4 psi and the other is 4-4 3/4 which I think is for the twelve.

A stronger electric pushing thru a mechanical pump and filter will drop some pressure by the time it reaches the carb and shouldn't cause any issues but a strong electric running directly to the carb might be too much for the float valves to control and the carb could flood or leak. If your electric is putting out in a range from 5-8 or more psi as many do you may need to think about a pressure regulator in the second line. If you go with a regulator be sure to get a name brand. Some of the less expensive regulators have been reported as pure junk when trying to regulate in a low psi range.