Register now to get rid of these ads!

Technical Carburetor issue

Discussion in 'The Hokey Ass Message Board' started by White_Attack, Mar 19, 2019.

  1. White_Attack
    Joined: Sep 4, 2010
    Posts: 177

    White_Attack
    Member
    from Oregon

    Looking for advice for my carb issue. It's an AFB Carter and it isn't spraying fuel into the bowl as it should, so the car won't start. I don't want to keep manually adding fuel each time I want to start it. It also has been rebuilt and adjusted if that makes a difference at all. My other buddy can't even figure it out. o_O
     
    chryslerfan55 likes this.
  2. Boneyard51
    Joined: Dec 10, 2017
    Posts: 3,806

    Boneyard51
    Member

    Are you saying the acceleratior pump is not working? If so, check linkage, pump, check valve, and see if the spray nozzles are clear. It’s been forty years since I worked on an AFB, so can’t give you any peticulars. Just the basic.




    Bones
     
    Last edited: Mar 20, 2019
  3. 6sally6
    Joined: Feb 16, 2014
    Posts: 1,032

    6sally6
    Member

    If it ain't spray'in.....look close at the accelerator pump!!
    6sally6
     
  4. Mike VV
    Joined: Sep 28, 2010
    Posts: 1,808

    Mike VV
    Member
    from SoCal

    It shouldn't...be spraying fuel into the "bowl" That should already have fuel in it..!
    It should be spraying fuel into the venturi/booster area.

    1. No gas in the carburetor.
    2. Accelerator linkage not connected.
    3. Throttle not connected.
    4. The spring and lock on the pump shaft (above the diaphragm) are not in place.
    5. No ones pushing on the gas pedal.
    6. The steel ball is not at the bottom of pump well.
    7. The steel ball is not in the squirter well location.
    8. The squirter is not in place.

    Bought all I can think of at this hour.

    Mike
     
    ClayMart and dan griffin like this.
    Register now to get rid of these ads!

  5. carbking
    Joined: Dec 20, 2008
    Posts: 2,716

    carbking
    Member

    loudbang, dan griffin and egads like this.
  6. DOCTOR SATAN
    Joined: Mar 21, 2014
    Posts: 711

    DOCTOR SATAN
    Member
    from okc

    Yes, accel pump.......
     
  7. BJR
    Joined: Mar 11, 2005
    Posts: 6,242

    BJR
    Member

    Political? I don't get it. :rolleyes: But I haven't had my 2nd cup of coffee yet.
     
    White_Attack likes this.
  8. egads
    Joined: Aug 23, 2011
    Posts: 659

    egads
    ALLIANCE MEMBER

    loudbang and BJR like this.
  9. OLDSMAN
    Joined: Jul 20, 2006
    Posts: 2,312

    OLDSMAN
    Member

    If you have to put gas down the ventures, then for some reason the accelerator pump isn't working. There are only two possibilities for that, the rubber seal on the pump has gotten hard or the passages to the nozzles or the nozzle itself are plugged
     
  10. egads
    Joined: Aug 23, 2011
    Posts: 659

    egads
    ALLIANCE MEMBER

    I think what carbking mean's is that you have to see if there is any fuel in the carb. After you prime it and let it run, shut it off and see if any fuel comes out of the shooter when you pump the throttle, if no, accel pump, if yes, fuel is evaporating when the engine is shut down for awhile. ( Ethanol blend's )
     
    loudbang, F&J, carbking and 1 other person like this.
  11. BJR
    Joined: Mar 11, 2005
    Posts: 6,242

    BJR
    Member

    Thanks, that makes sense now.:)
     
    egads likes this.
  12. carbking
    Joined: Dec 20, 2008
    Posts: 2,716

    carbking
    Member

    From the troubleshooting page I posted above:

    Accelerator pumps

    Often the accelerator pump gets the blame for other problems. It is very easy to test the function of the accelerator pump. Start the engine, and warm to normal operating temperature. Shut off the engine. Remove the air cleaner. The choke butterfly should be fully open, as the engine is warm. Observe the pump jet in the carburetor, and with your hand, work the carburetor throttle to the wide-open position. You should observe a healthy squirt of fuel from the pump jet. A single barrel carburetor will normally squirt a single stream; while a two or four barrel carburetor will normally squirt 2 streams. If you see the stream(s) of fuel, the pump is working. It is important to start the engine prior to doing this test. With modern gasoline, it is quite possible the carburetor will be completely dry prior to starting. If there is no gasoline in the bowl, the pump will not work; and this would give a false result.

    Jon
     
    loudbang, White_Attack and egads like this.
  13. s55mercury66
    Joined: Jul 6, 2009
    Posts: 3,981

    s55mercury66
    Member
    from SW Wyoming

    Could the float level be so low that all of the fuel evaporates when the engine is shut off? If so, that would explain why it may have a good pump shot while running, and none when trying to start it after it has cooled down (and the fuel has evaporated). I have also had weak fuel pumps on quadrajet equipped small block chevys do the "needs primed to start after sitting" deal on me.
     
  14. partsdawg
    Joined: Feb 12, 2006
    Posts: 2,614

    partsdawg
    ALLIANCE MEMBER
    from Minnesota

    Just because a carb has been rebuilt doesn’t mean it was done right.
     
    swade41 and dan griffin like this.
  15. s55mercury66
    Joined: Jul 6, 2009
    Posts: 3,981

    s55mercury66
    Member
    from SW Wyoming

    Exactly, and just because a carb is new, does not mean it functions properly.
     
  16. White_Attack
    Joined: Sep 4, 2010
    Posts: 177

    White_Attack
    Member
    from Oregon

    It actually worked fine after the rebuild for quite some time. Even drove around the country side without issue & ran strong.


    Sent from my iPhone using The H.A.M.B. mobile app
     
  17. White_Attack
    Joined: Sep 4, 2010
    Posts: 177

    White_Attack
    Member
    from Oregon

    I will check it out


    Sent from my iPhone using The H.A.M.B. mobile app
     
  18. White_Attack
    Joined: Sep 4, 2010
    Posts: 177

    White_Attack
    Member
    from Oregon

    Very helpful. Thanks.
     
  19. irishsteve
    Joined: Jan 10, 2017
    Posts: 657

    irishsteve

    The accelerator pump shaft on those are plastic.As they get older they develop a curve.This curve causes it to not travel correctly.Disconnect its linkage,and the shaft may lean to one side.It shouldnt.
     
  20. deathrowdave
    Joined: May 27, 2014
    Posts: 2,116

    deathrowdave
    ALLIANCE MEMBER
    from NKy

    If I remember correctly , and this maybe on the timeout bench now for me . The pump on an AFB was leather , if a rebuild it maybe gone by now anyway . If it is still a leather pump and it drys out it usually takes a bit for it to gas soak and swell up to work properly again after a timeout also . Any help here on this memory issue ?
     
  21. That sounds kind of familiar to me too. And it seems like at least some of the carbs with the leather pump seal also had a small garter spring inside them that helped load the seal against the inside of the accelerator pump well. Don't remember ever seeing one come out of place but there's always a first time for everything. :rolleyes:
     
  22. carbking
    Joined: Dec 20, 2008
    Posts: 2,716

    carbking
    Member

    Haven't seen this, but I make my own rebuilding kits. We use brass shafts, not plastic.

    Jon.
     

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2020 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.