Author Topic: AC Fuel Pump Rebuilds  (Read 360 times)

Jerry@CHP

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AC Fuel Pump Rebuilds
« on: April 17, 2025, 05:04:03 PM »
For everyone on CRG, I just posted this on Facebook.  Just an FYI for you. 

For all the gear heads out there, had an unfortunate issue pop up yesterday with the Green monsta.  Started it up and pulled it into the shop only to find gas hemorrhaging through the vent tube and down into the venturi's. Took it all apart, cleaned the needle and seat installed a new power valve, put it back together same problem. Installed another carburetor and had the same issue. Called a friend and he told me it could be an issue with the calibration of the fuel pump. I pulled the pump off and installed a good used pump on the Shelf and the problem went away. I don't know who is restoring or rebuilding these AC fuel pumps but evidently the pump on my car worked well for two years and then all of a sudden the calibration went South. Just some food for thought if you're having your original AC pump rebuilt. In my stock Eliminator race car I run 7 lb of fuel pressure and that's no problem for a Holley carburetor. So for this mechanical pump to fail it had to be pushing anywhere between 10 to 12 lbs of fuel pressure to the carburetor. For many car guys who don't work on their own stuff just be warned that this problem could crop up if you've had an original AC pump rebuilt.  Notice the two simulated adjusting screws on the back of the pump. Factory pumps are not built like this.

rocco376

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Re: AC Fuel Pump Rebuilds
« Reply #1 on: April 17, 2025, 06:25:32 PM »
Thanks, Jerry. 

x66 714

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Re: AC Fuel Pump Rebuilds
« Reply #2 on: April 17, 2025, 08:39:04 PM »
The one Jerry has a picture of on FB is NOT a Fred Ballard pump. In another post Jerry indicates he gets his pumps from Goathill through another vendor. Goathill is the company that many other site have warned to stay clear of. Fred Ballard build a quality pump....Joe 
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MO

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Re: AC Fuel Pump Rebuilds
« Reply #3 on: April 18, 2025, 05:19:05 AM »
Thanks for the heads up Jerry!

dannystarr

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Re: AC Fuel Pump Rebuilds
« Reply #4 on: April 18, 2025, 05:39:07 PM »
I had trouble with this issue MANY years ago. Car would NOT run and smoked. Fuel blowing by needle and seat. On advice from an old mechanic friend, I installed a $15 fuel pump from pep boys and problem solved. I said can I do THIS, or THIS. He said STOP. Don't tell me about anything until you install the cheapy pump and check the pressure. He was correct.
 No matter what I asked, the rebuilder could not tell me what the final pressure would be at an idle or running down the road. So I did some experimenting. I wanted to retain the visual of the double AC embossed pump on several cars. I ended up hiding a pressure regulator in the first few inches inside the right frame rail. It has holes in the steel to run the lines. Did that to 4 or 5 different cars. Works great and nobody has ever noticed it after over 100 car shows. In fact, I just saw some light blue staining on one while I had it on the lift. Which is AVGAS. Guess I better take a look at that and see if it can be fixed. Or maybe just replace it. CRAP!!! I just looked at another car on a different lift and it has MORE blue stains on it. Always something with old cars. Danny
                    https://www.youtube.com/watch?v=UqAz0koDSpQ
                   
                    https://www.youtube.com/watch?v=QdEhsJqryNc
                   
                    https://www.youtube.com/watch?v=JwxHpvT9vP0