k20 350 Fuel problem over 40?

Discussion in 'Tech Discussion' started by Project_82k20, Jun 12, 2018 at 1:03 PM.

  1. Project_82k20

    Project_82k20 Junior Member

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    I just bought an 82 k20 with a 350 in it. The guy said that it just needed an electric fuel pump to help the mechanical one. I knew that the mechanical one was fine and just figured it was something with the carb. However i cannot seem to figure it out. Anything over 40 or when you step on it it sputters and seems to be getting not enough fuel. Any suggestions? thanks
     
  2. 4WDKC

    4WDKC Full Access Member

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    floats adjusted correctly? checked the spark plugs for carbon build up from being to rich? check timing? did you rebuild the carb recently? Checked fuel pressure mech. pump might be week.
     
  3. WFO

    WFO Full Access Member

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    Welcome from the Texas Panhandle.

    Float, filter, or clogged fuel supply.
     
  4. HotRodPC

    HotRodPC Administrator Staff Member

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    All these things and it could be the fuel pump or cam lobe that operates the fuel pump and it's not getting enough volume to keep at 40. You could get one of those clear plastic fuel filers and hook it inline to where you can see the fuel volume it's pumping.
     
  5. rpcraft

    rpcraft Full Access Member

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    I'd probably look to add a clear filter but also replace the fuel pump. They are cheap to replace, not too terribly hard (if you have swapped to flexible lines) and they don't last forever. If the diaphragm is getting cracks and leaks it just starts having issues metering out the proper volume at higher engine speeds.
     
  6. HotRodPC

    HotRodPC Administrator Staff Member

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    I'd agree, but first off we'd need to determine if it's the fuel pump or the cam lobe. I've seen where cam lobes get wore down and they don't work the actuator arm very good and even a new pump can't keep up. It's not extremely common, but it somewhat common for the fuel pump cam lobe to get wiped out. The seller might know something we don't and why he suggested it needed an Electric Fuel pump.
     
  7. rpcraft

    rpcraft Full Access Member

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    That is a good thought. I know it's not common but it's definitely a pre-cursor to when things go wrong, like low oil pressure or low oil level.
     

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