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fuel delivery issues ain't getting none

Discussion in 'Carb Fuel Systems' started by DanMcG, Apr 6, 2020.

  1. DanMcG

    DanMcG Supporting Member Supporting Member

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    Well that worked, blew some some air in the tank, blew gas a few feet. I tried cranking it over after that figuring it was primed and nothing, not a drop pumped by the pump.

    Thanks everyone, especially Snooks for the suggestions. I got a couple days before the new pump gets here from Rock auto so I should have plenty of time to get the old one off.
     
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  2. DanMcG

    DanMcG Supporting Member Supporting Member

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    I'll keep that in mind, thanks.
     
  3. Ricko1966

    Ricko1966 Full Access Member

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    Sorry it was an e8090 airtex
     
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  4. DanMcG

    DanMcG Supporting Member Supporting Member

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    Well I'm sitting here waiting for the rain to stop before I get the new pump on, and was thinking.....If the old pump was weak, would that explain why the carb bowl is empty? Is it possible that it was only pumping enough to get it to run, then when it sits for any period of time what little is in the bowl evaporates. Hasn't been on the road in a while so it only idles in the yard and any attempt to give it gas it stumbles.
     
  5. Snoots

    Snoots Supporting Member Supporting Member

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    I had a similar problem many years ago.

    Fuel pump died.
    Replaced fuel pump.
    Didn't help.
    Come to find the new fuel pump was for a 2-bbl carb.
    Got one for a 4-bbl carb.
    Problem solved.

    Don't forget this:

    fuel pump bolt.jpg

    You'll need a longer bolt to hold the push rod up while installing the new pump.
     
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  6. DanMcG

    DanMcG Supporting Member Supporting Member

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    It funny but that boss for the bolt must not be drilled thru to the rod as there is no bolt in it and no oil seepage. Maybe because it's a 86 warranty block?


    Well it's in and working great, but now the 5/16 return line is spraying gas out of cracks in the line. never saw them till now, so thats next on the list.
    Thanks everyone who helped, I appreciate all the advice.
     
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  7. AuroraGirl

    AuroraGirl Supporting Member Supporting Member

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    Say what now. There are different pumps for 2 barrels? Mine had a two barrel. It does keep up while running but still. Interesting
     
  8. Snoots

    Snoots Supporting Member Supporting Member

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    I thought it was odd too but, the 4bbl pump was taller through the chamber than the 2bbl model.
    I don't know :confused: but it works.
     
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  9. AuroraGirl

    AuroraGirl Supporting Member Supporting Member

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    What issues did it cause in yours? Was it a new 2 barrel pump that didnt seem to work right out the box and a new 4 barrel pump that did?
     
  10. Snoots

    Snoots Supporting Member Supporting Member

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    It would start ok
    It would idle ok
    It would take off slowly
    Then just acted like it ran (or was running) out of gas at about 20MPH.

    The 4bbl pump I got just had a larger diaphram area.

    Oddly, the new pump I recently installed (about 3 months ago) has a smaller diaphram area and so far, has posed no problems.

    I've even punched it from 75MPH and it scoots. I'm running the same Q-Jet.
     
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  11. AuroraGirl

    AuroraGirl Supporting Member Supporting Member

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    Curious. Thanks for the input and response to old thread
     
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  12. Snoots

    Snoots Supporting Member Supporting Member

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    I wish I had a more definitive answer for you but it baffled me. Even the original pump had a large diaphram but it sprang a leak in the casing so initially, I thought the small diaphram was better technology.

    If it works, I ain't fixin' it.
     
  13. DanMcG

    DanMcG Supporting Member Supporting Member

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    You got me wondering about this 2bbl-4bbl thing so I looked around a little. the pump for a six cylinder looks the same but with less pressure and gpm. :shrug:
     
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