1. Registration trouble? Please use the "Contact Us" link at the bottom right corner of the page and your issue will be resolved.
    Dismiss Notice

suitable fuel pump?

Discussion in 'Early CJ5 and CJ6 Tech' started by unclebill, Apr 29, 2009.

  1. unclebill

    unclebill Banned

    for some reason i just remembered.
    the arm i guess you would call it wasnt resting in the right spot when i put it on.
    so it wasnt working
    i took it off and put the arm on the TOP of the hump where it needed to be.
    then it worked fine
    and it cost 30 bucks
     
  2. SCF

    SCF New Member

    This is my next venture, replacing the fuel pump. I'm replacing the original one with the vacuum setup, with a non-vacuum Airtex version. Do I just plug the vacuum lines, or hook them together?
     
    Last edited: Jan 14, 2011
  3. givemethewillys

    givemethewillys Been here since sparky ran it. 2022 Sponsor

    I think either way will work, but more knowledgable people will have to chime in
     
  4. SCF

    SCF New Member

    So I'm in the middle of installing this thing, and it feels like the bolt closest to the fan wants to cross thread. Kind of a pain in the butt to get to it, especially knee deep in snow. Any tips/tricks?
     
  5. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Run a tap through the hole before you put the bolt in. Use a new bolt, or clean up the threads on the old bolt.
     
  6. Walt Couch

    Walt Couch sidehill Cordele, Ga. 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Also get the hard one started first..
     
  7. Steve's 70-5

    Steve's 70-5 Active Member

    Run the bolt in with no pump on and see how it feels
     
  8. SCF

    SCF New Member

    Thanks all! Now all I need is some POSITIVE temperatures to try it out! Brrr!
     
  9. mainejeep

    mainejeep Member

    good luck im dealing with the same temp problems today it was -5 wo the wind chill
     
  10. Diggerjeep

    Diggerjeep Member

    Consider replacing the fuel pump with an electric one. If your old pump has the vacuum lines, and the vacuum lines work fine, leave it alone.

    I prefer a small electric fuel pump for a couple of reasons.

    First, the pump works (pumps gas) without the engine running. So if the jeep hasn't run in a while, you may have to crank the engine over a bit if before gas can even get to the carb. Likewise if your fuel guage doesn't work and you run out of gas, you have to crank a bit to get gas to the carb before the engine will start.

    The problems on the site talk alot about knot knowing if fuel is getting to the carb. With an electric fuel pump, this makes the problem simple. Just pull the line of the carb and turn on the pump quickly, and see if gas comes out.

    I have an outboard switch on the dash which allows the pump to turn without the ignition switch. If you hide the switch, it makes a simple theft deterrent.

    If the jeep or one of my other car with an electric fuel pump hasn't run for a couple of weeks, I turn on the fuel pump for a bit before I start then engine. You can hear the electric fuel pump rattle until it quiets down once the fuel pressure builds. Then you can pull the choke and crank the engine, knowing that there is fuel in the bowl.

    If the jeep doesn't have a fully charged battery, the battery can be run down before the fuel pump gets gas to the carb to start it.

    You can get an electric pump for about $45.00.
     
  11. GreenGhost

    GreenGhost Never give up!


    Somtimes the switch fails and leaves you sitting in the middle of a busy intersection as all your classmates and teachers drive-by pointing and chuckling at your misfortune.:(
     
  12. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Generally, the mechanical pumps fitted to carbureted engines are very, very reliable. Even so, I used to carry a replacement pump with me ...

    An electric pump has its own issues. First, they must be plumbed correctly. Since they are basically pusher pumps, if the fuel delivery system springs a leak, they will pump gasoline out the hole until the switch is turned off or the tank runs dry. This can be a serious fire hazard - BTDT (not my car or my work, but a first-hand experience).

    You should use all hard line and short lengths of high-quality hose to connect the pump. Long rubber hoses are an invitation to a bad fire, a total-loss fire where you will be happy you got out without serious injury.

    Additionally, the electric pump will continue to pump in a wreck or roll-over, as long as the key is on. This is a specific issue with carbureted vehicles, not with FI vehicles. The best way to wire an electric pump is with an oil pressure switch, so that if the engine shuts off, the fuel does too. Unfortunately, this removes the advantage of the electric pump filling a dry bowl. I can imagine some work-arounds that would get around this problem, but they will make the wiring and operation of the fuel pump more complicated.

    So I'd say, keep your mechanical pump unless you have vapor lock problems. An electric pump is very effective at overcoming vapor lock. Then, take care that your pump installation is properly plumbed.

    hth!
     
  13. JAlves

    JAlves Sponsor

    Another Option

    You can run an electric pump and the mechanical in series. The electric can be switched on to prime and turned off once the engine is running. I have only done this with a diaphragm pump and am not sure it will work with a rotary vane type.

    They could be run parallel but the plumbing around the mechanical pump will complicate the installation.