Fuel Pump rebuild/test
 

Just rebuilt a EV-8 Holley fuel pump, (see photos), with a NAPCO kit, (made in Japan). Is there a way to bench test a fuel pump to see if it works ok ?


The reason I ask is the rocker arm and lever are different than the originals.
See photo. The top one is the 2 piece Napco. The middle 2 piece one was in 1 original Holley, and the bottom one piece arm was in another original Holley.


The Napco has a hole slightly larger than the pin, the #2 version has a much larger hole than the pin, and #3 version has an elongated, oval hole.


Thank you Fordbarners.

Re: Fuel Pump rebuild/test
 

Top and middle are the same basically....the Holley requires a hardened bushing. Bottom arm is the latest style . Pretty much all off shore pumps use this arm....seems to work
ok. If there is a choice I like the Holley arm with a bushing....more substantial.

IMHO my test motor is invaluable, in lieu of possessing vintage Ford test equipment.
Charlie ny

Re: Fuel Pump rebuild/test
 

Got a PM asking where you get the NAPCO 11A-9349 kit. Joe's Antique Auto.


Here is blowup of the pump to aid in rebuilding. Charlie NY rebuilds them, and recommends the Holley arm w/bushing. See attached photo blowup of the pump from the green bible showing the bushing. The kit just uses a pin and arm, no bushing. I didn't test the pin or arm, by the appear to be hardened.

Re: Fuel Pump rebuild/test
 

I’m working on a early pump now,and used a mighty mite to draw vacumn on suction, didn’t hold a vacumn,changed gasket on top and around screw,got a little better,them plugged out let of pump and held vacumn,might need to check the check valves next or the
dia,,have a new kit but just checking it first. Don

Re: Fuel Pump rebuild/test
 

As Charlie does, the ONLY way to test them is on a engine or a KRW wilson tool meant to test them. I am fortunate enough to have a test stand engine, and I usually use the KRW tester. You'd be surprised how many test well by hand but on a engine won't pump due to arm travel issues, related to the arm or diaphragm.

But..... With the Napco kit you should be fine.. I personally do not like the check valves in the kit but otherwise, very good. We stock them in large quantities and I just swap the valves out for something I like a bit better. On the Napco kits you usually should slightly grind a small amount off of the 'hum" on the arm or it can bind in a diaphragm.

Re: Fuel Pump rebuild/test
 

one important note.make sure the digeram. spring has the same tension .that sets the fuel pressure

Re: Fuel Pump rebuild/test
 

Since I do not have (10) posts it won't let me make URL links so I added spaces to the URLs

I stumbled across this post with a Google search for the NAPCO 11A-9349.
I thought I would leave some additional details, links, information on what else I found to help others.

I scanned page 367 out of my personal copy of the "Ford Truck Chassis Parts Catalog", creating a searchable PDF. I put it up on SCRIBD.
Fuel Pump 8 Cylinder 239 Engine
www .scribd .com /document /747565127/ Fuel-Pump-8-Cylinder-239-Engine

There are also 2 youtube videos that helped me.
"FUEL PUMP REBUILD & RESTORATION - Ford Flathead Engine - How to" by Chad Drake
youtu .be /WWbcc1teqEQ ?si=bFH5W9TaOnNcY_iz
"Rebuilding Ford Flathead Fuel Pump!" by Wired Customs
youtu .be /wgpUSXK_0Ls ?si=-9SoI-FJPc-ujXfB

Re: Fuel Pump rebuild/test
 

Typical is the two piece arm. If the hole is larger than the retaining pin the kit should have a small sleeve that is also in the hole, the retaining pin passes through the sleeve.

Just a rebuilding hint after assembly check out the end play, if excessive a washer or shrink the sides of the housing so the arm moves freely up and down but not sideways. Sideways motion will decrease pump output.