Fuel pump repair kit

[Knightowl61]

I like the idea of the original pump with the sight bowl & manual pump lever. I bought the kit from SS and used the diaphram but the check valves seem to be leaking after the engine warms up.
Question - how do you pull the check valves out? I tried prying with a screwdriver and twisting with needlenose pliers to the point that something might break and I'll never get them out.

 

[BEpine]

When I replaced mine, I used a die grinder with a 1/8 bit and carefully ground the area that was staked over the valve.
After installing the new valve used a center punch to stake in the new valve.
Bob

 

[Acollin]

Why would it be leaking after the engine“warmed up”?
I would assume things would be leaking with the simple cranking of the motor— even before the car actually started.
curious here
Andrew

 

[Knightowl61]

Why would it be leaking after the engine“warmed up”?
I would assume things would be leaking with the simple cranking of the motor— even before the car actually started.
curious here
Andrew

It starts easily when it's cold, you can finger pump it also. After a short run and turning off for about 10 minutes then going to restart it just cranks. Trying to manually pump the gas can't get half way up the glass bowl. After cold again the bowl fills up with just a couple pumps.

 

[Acollin]

Pardon my thick head, but I do not see how the car being warmed up would effect the leaking . As I understand it, the car would be pumping gas both warm and cold. While the pump may not be functioning properly all the time therefore not leaking all the time, I am still confused by your original statement “ leaking after the engine warms up”. If the car is running for “10 minutes”, I would assume it would be leaking for 10 minutes. No disrespect intended, I’m simply confused.
is the car not leaking when it is cold and running?

 

[Shannon Boal]

I don't know what is happening here, but....Pouring cold water on a fuel pump that is failing may get it to work for about twenty minutes. Ralph and I made it from Knoxville to Dayton that way...We replaced his series V pump in Dayton. He later said that his valves inside the pump had come unstaked.

 

[GlennB]

I can vouch for the fact that a mechanical pump can be marginal and only actually exhibit failure symptoms when other factors are adverse, like temperature and volatility of fuel.

 

[Mike O'D]

Some air is almost always trapped inside the glass bowl - it's upside down and you are filling it with liquid. When it's hot, the air expands and lowers the level of fuel inside. When it's cold, the air shrinks and you can put more fuel inside it. I don't think that's what is causing the hot starting issue, and I don't think it's "leaking".

 

[Knightowl61]

Pardon my thick head, but I do not see how the car being warmed up would effect the leaking . As I understand it, the car would be pumping gas both warm and cold. While the pump may not be functioning properly all the time therefore not leaking all the time, I am still confused by your original statement “ leaking after the engine warms up”. If the car is running for “10 minutes”, I would assume it would be leaking for 10 minutes. No disrespect intended, I’m simply confused.
is the car not leaking when it is cold and running?

After replacing the second check valve I tested the car on the local back roads again for about 10 minutes. No windshield and doors held with bungee cords, max speed 30mph. With an unknown 1725 and automatic trans I wanted to see how the car would run on it's own.
It starts easily when cold and ran ok for the 10 minutes or so. Again after stopped for 10 min. or so it wouldn't start. I disconnected the fuel line at the carburetor and manually pumping into a jar only got one little spurt of gas then nothing (tried 10-15 pumps). Walked away for a couple hours then tried pumping again into the jar and after a couple pumps gas was gushing into the jar with each pump.
Either a check valve, diaphram, or something is letting gas leak back instead of pumping forward when hot.
Ordered another fuel pump repair kit. Also the pump does have the thick insulation spacer to the block.

 

[ColinLM]

F W I W I rebuilt the manual pump on my S V last winter.
I used a pick with a bent end to coax the check valves out and an appropriately sized socked and small hammer to place the new ones in position.
I too encountered irregular operation after reassembly. Upon careful examination of the pump diagram in the WSM on this site I found I had installed the diaphragm rotated 90 deg off from where it should be.
Careful reassembly cured the problem.

 

[Knightowl61]

I installed the second new repair kit on another spare pump top end and replaced the diaphram from the newest kit per wsm instructions. Engine ran good ideling for 10 - 15 minutes then died. pulled the gas line from the carb and no gas while cranking or manual pumping. I can see a stream of bubbles coming from the base of the glass bowl ( almost same as the first try}. The first time I crimped the line going to the carb and it stopped bubbling. This time pump to carb made no difference and crimping the line to the pump made little difference.
I don't think vapor lock is the problem - metal line to engine bay, then rubber hose near inner fender to the pump, and rubber line from pump going out over the engine and valve cover to the carb (95% open air). No gas found leaking anywhere.
WIT'S END! HELP

 

[sunalp]

How is your gas tank and lines? Could be that there's crud in the tank and takes about 9-10 minutes to block the
flow of fuel. It wouldn't be the first time that's happened.

 

[Knightowl61]

Cleaned and coated the tanks and ran all new metal lines.then rubber fuel lines and filter in the engine bay.

 

[Knightowl61]

Now replaced top and bottom parts of the fuel pump with all new gaskets. Again same problem, no pumping gas when hot.


If I crimp the inlet or outlet hose the bubbles lessen. If I crimp both hoses the bubbles stop.
The only thing I can think of is that I damaged all 4 check valves, BUT ONLY WHEN HOT??

 

[bulldurham]

pump lever on correct side of cam ? you h ave covered just about everything else

 

[Mike O'D]

This may not have anything to do with your situation, but if the cam stops on the high spot at the fuel pump arm, manual pumping doesn't work.

 

[Shannon Boal]

Possible to analyse this system by isolation, unhooking lines from pump. Plumb a fuel pressure/vacuum gauge to the pump inlet and test while cranking or running engine. Inlet should pump to 18 plus inches of vacuum and hold that indefinitely. The volume test for the outlet is the best test I know, but you can pressure test the outlet; it too should not leak down. Further testing possible: plumb into inlet with a tee, and run at road speed to test for restriction in supply (should not exceed 2" vacuum in twenty minutes steady cruising). It is time consuming but gives clarity....

 

[Knightowl61]

This may not have anything to do with your situation, but if the cam stops on the high spot at the fuel pump arm, manual pumping doesn't work.

Good to note, but cranking or manually pumping - hot no gas - cold good surges. I'm ready to give up.

IDEA -to keep original looking could I put an electric pump near the spare tire and leave everything else the same?
If not I should be able to pop out the check valves and pull out the lever assembly.

 

[Shannon Boal]

One other test, plumb gauge to end of fuel pipe at rear of vehicle which goes to fuel pump inlet, run engine. Should reach 18 plus inches (takes longer to pull vacuum on long line) and it should hold that. My thinking is a leak in that line would produce your symptoms. Cold it may suck fuel and a little atmospheric air; hot the fuel vaporizes instead of being drawn. Or, a combination of restriction and leak back there. One last thought, since you worked on the rear fuel system, there is a chance the problem originated with that work.

 

[sunalp]

Have you tried a different pump, such as an electric one just to see if it's any different?