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Topic: Adding Primer Pump and Extra Filters, Have Questions... (Read 488 times) previous topic - next topic

Adding Primer Pump and Extra Filters, Have Questions...

I am almost finished collecting everything i need to replace my gas tank and while there i want to add a "primer" fuel pump setup, which is external but since ill be in the proximity the work will be done then, for my thunderbird and had some questions or just interested in opinions regarding what im doing.
This is on a 1983 thunderbird with the CARBURETED 3.8 v6.

To start, if you are not aware a primer pump is a very low pressure fuel pump(less than 3 psi) typically used on things like boats and generators. The particular type i selected it a flow thru type which allows fuel to flow thru while its not running. Line size for all is at 5/16 I/D.

The [objective] purpose for this is that since i let my car sit for long periods i would like to not have to crank for long periods to get it started when i feel like using it, and basically extend the motor and starters lifespan. The car runs fine on its motor driven fuel pump so i am not interested in a full time electric pump setup like some people do to their classic cars.

The setup will consist of the primer pump, a fuel filter between the gas tank and the pump and a bypass hose "tee"d in before and after the pump with a fuel line check valve in the bypass hose.
Under the hood ill be installing another fuel line check valve before the fuel pump and all new fuel hoses since they are 40 years old.

One question i have is will adding all these cause enough of a restriction to give me starvation issues?
Im looking at the largest in line fuel filter i can get away with before the pump just to have some capacity incase of a restriction.
The main reason im adding a bypass line is even the pump is flow thru it doesnt feel like it will "fully" flow thru at the rate an unresticted line will and as a precaution the bypass will draw from the line of least restriction... hopefully. The inline check valve should prevent fuel from going down the bypass during priming and basically recycle the fuel around. Im hoping it doesnt create an air pocket in the line or collapsing and stopping fuel all together.
Ive never used inline fuel check valves before so i dont know what their effect on restricting flow on low pressure draw thru systems are.
The running fuel pressure is only about 8 psi but its harder to measure "amount" of fuel being pulled thru the system without it being in use.

I would like to believe this will work without a hitch but my gut tells me im overlooking something.
Any input or experience here would be appreciated.
"Beating the hell out of other peoples cars since 1999"
1983 Ford Thunderbird Heritage
1984 Ford Mustang GT Turbo Convertible


Re: Adding Primer Pump and Extra Filters, Have Questions...

Reply #1
So after researching this more deeply i see that basically choosing a pre pump filter finer than 10 microns would likely cause the mechanical fuel pump to wear faster due to the increased restriction from it.
"Beating the hell out of other peoples cars since 1999"
1983 Ford Thunderbird Heritage
1984 Ford Mustang GT Turbo Convertible