New fuel pump drowning carb?

Cougar Community Classic Cougar Maintenance Restoration and Repair
1

Hi! My old fuel pump was leaking so I replaced it (1968 XR7/302). Started up high idle, I bipped it down… she idled. I can see fuel in the filter by the carb. And she just shut off.

I tried a restart and no dice. When I pull the accelerator linkage on the carb it squirts fuel happily.

Coincidentally I have a battery that’s not in great health. Could these be related or coincidental? I have a pertronix coil that’s about 3 years old with limited use

Today I started it up and it looks like it’s drowning itself… do I have a pump with too much flow?

2

Seems more likely that debris from replacing the pump is keeping the carb needle valve from closing. While the carb is open, you can make sure the float still floats too.

3

I can check that but when installing the new pump, I had lots of gas pour on me… so I think that’d be a lower probability but good to call out for sure.

4

Looks like your Holley carb has a stuck needle / seat assembly. That is not a fuel pump issue. Your carb needs rebuilding.

5

If your needle valve is stuck open, the carb bowl will empty through the fuel line when you remove the pump.

6

So, I pulled the needle out, checked it for debris , blew it out with carb cleaner for good measure in the little jet… reinstalled it, car starts in high idle… after about 15 seconds she pushes gas out the vent again, albeit less this time (maybe because I was watching for it). I don’t think, think, a float adjustment would cause it to vent fuel. Could it be fuel pressure? Or still a clog somewhere?

Could the rear needle be clogged also? I haven’t seen any gas from it’s vent.

My little clear fuel filter is fuller than ever before with the old pump. Could be coincidence?

7

The problem is with the front float bowl. Could be trash in the gas, bad float, worn out needle / seat or a host of other reasons.

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8

Spend the money and replace the needle and seat.

9

I would have the carb. cleaned and rebuilt. Pay the extra for a good Carb, man to do it. It will be worth the extra money. Also be sure to replace all filters. Beware of todays gas…its got water in it. Keep fresh gas in the tank…for me that means only 5 gallons at a time. Start motor regularly and let it warm up.
I let my mustang sit for a long period of time and paid the price for doing that.

10

Lots of issues with today’s fuel pumps putting out too much pressure. Precision pump from O’Reilly are one culprit. I have had very good luck with Carter pumps on my fleet.

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11

Hi! To close the loop here after I put in a Mr gasket fuel pressure regulator, checked with Holley on proper pressure that my carb likes, reset the float heights she once again purrs like a kitten. I need proper washers for one of my needle assemblies because one ripped in half as I pulled the needle out for good measure (no debris discovered but I blew both out with carb cleaner). Thanks for everyone’s guidance!

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