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  •  » Acceleration problem

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    4/09/2015 5:46 PM  #1

    BillyC
    I FYI 24-7

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    From: Chesapeake, Va.
    Registered: 4/02/2013
    Posts: 966

    Acceleration problem

    66 coupe 289, stock bottom end and heads, Edelbock performer carb and manifold, mechanical fuel pump, Pertronix ignition and coil (resister wire removed). T5 trans. My problem is when I accelerate aggressively (not floored) the motor cuts out for a split second then continues to run fine. When I say a split second I mean it sounded like something broke the first time it happend but I tried it again watching the tach and the revs dipped momentarily. Sometimes it will miss several times at around 3000 rpm when I'm accelerating fairly hard. Driving normally it runs perfect. But driving "normal" ain't no fun.

    "anyone that stops learning is old, whether at twenty or eighty"Henry Ford
     

    4/09/2015 5:50 PM  #2

    6sally6
    Hyper FYIFORD ADDICT

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    From: Surfside Beach,SC
    Registered: 4/02/2013
    Posts: 6,884

    Re: Acceleration problem

    Check plugs and wires first!
    easy and cheapest first!!

    Get busy Liv'in or get busy Die'n....Host of the 2020 Bash at the Beach/The only Bash that got cancelled  )8
     

    4/09/2015 5:58 PM  #3

    barnett468
    Banned

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    Registered: 9/15/2014
    Posts: 770

    Re: Acceleration problem

    how long has it been doing this?

    did it start immediately after you installed s new part?

    i would do the following first then test drive it . . set the screw 2 turns in, not 1 1/2 . . leave it at 2 turns until your prob is fixed.

    https://www.youtube.com/watch?v=lkj4oL5CDg0

     

     

    4/09/2015 9:27 PM  #4

    Pablo
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    From: Georgetown, Texas
    Registered: 4/12/2013
    Posts: 248

    Re: Acceleration problem

    Billy, do you still have the instructions that came with the Eddy carb?  Check to be sure all the settings are exactly as mentioned in the instructions.  Then, you have a good starting point for "fine tuning" the carb.  Sounds like you may have an accelerator pump issue. That's assuming you have the stock distributor with a Pertronix module - right?

     

    4/10/2015 7:20 AM  #5

    GPatrick
    Senior 24-7 FYI Addict

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    Registered: 4/01/2013
    Posts: 1,117

    Re: Acceleration problem

    It sounds like an accelerator pump or mixture issue but you can get a momentary drop out if you have vacuum advance hooked up to manifold vacuum rather than a timed port.  When you mash the accelerator you lose manifold vacuum and the the timing will back off momentarily.  If the vac. advance is hooked up properly then look to your accelerator pump, idle mixture which affects transition, and base mixture.  What size carb?  

     

    4/10/2015 8:03 AM  #6

    BillyC
    I FYI 24-7

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    From: Chesapeake, Va.
    Registered: 4/02/2013
    Posts: 966

    Re: Acceleration problem

    I haven't changed any parts in a while. Plugs and wires were new winter '14. The carb is a 600.

    "anyone that stops learning is old, whether at twenty or eighty"Henry Ford
       •Thread Starter
     

    4/10/2015 8:56 AM  #7

    6sally6
    Hyper FYIFORD ADDICT

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    From: Surfside Beach,SC
    Registered: 4/02/2013
    Posts: 6,884

    Re: Acceleration problem

    I'd take the top off the Eddy carb(easy-enough) and clean/spray inside bowls and jets. Especially if you us eythanol gas. Maybe move the accelerator pump arm up one notch. See what happens. Once you're satisfied the carb is in good shape.....move on to timing/vacuum leaks/ignition.
    Mine started acting up like yours and discovered the battery had a bad cell......MSD wasn't getting enough juice  when I nailed-the-throttle...causing a miss at higher RPM's.
    It's the little things that make working on a hot-rod so much....
    "fun"!!

    Get busy Liv'in or get busy Die'n....Host of the 2020 Bash at the Beach/The only Bash that got cancelled  )8
     

    4/10/2015 12:36 PM  #8

    jkordzi
    I FYI 24-7

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    From: Sequim, WA
    Registered: 12/28/2013
    Posts: 927

    Re: Acceleration problem

    BillyC wrote:

    66 coupe 289, stock bottom end and heads, Edelbock performer carb and manifold, mechanical fuel pump, Pertronix ignition and coil (resister wire removed). T5 trans. My problem is when I accelerate aggressively (not floored) the motor cuts out for a split second then continues to run fine. When I say a split second I mean it sounded like something broke the first time it happend but I tried it again watching the tach and the revs dipped momentarily. Sometimes it will miss several times at around 3000 rpm when I'm accelerating fairly hard. Driving normally it runs perfect. But driving "normal" ain't no fun.

    If this issues started after you installed the carb, then that's where I'd look.  Does it only happen at specific RPM?  Only under a fairly hard acceleration, or anytime you get to that RPM?

    Cheap, Fast, Good:  Pick Any Two
     

    4/10/2015 3:18 PM  #9

    Derek
    I FYI 24-7

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    From: Eatonton GA
    Registered: 4/01/2013
    Posts: 549

    Re: Acceleration problem

    It's probably the squirters. You may have to go to a larger set.

    It's hard to type "funny"
     

    4/10/2015 5:25 PM  #10

    SA69Mach
    FYI FORD Member

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    Registered: 3/19/2015
    Posts: 29

    Re: Acceleration problem

    Check around the carb and intake for leaks.  It sounds like either a vacuum leak or a failed accel pump/blocked squirter, or badly adjusted accel pump lever

    1970 coupe  302 T5 Titanium Smoke 8.8 3.73 tru-trak  and 1969 Mach1 351W Black Jade PS PDB FMX
     

    4/10/2015 5:33 PM  #11

    BillyC
    I FYI 24-7

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    From: Chesapeake, Va.
    Registered: 4/02/2013
    Posts: 966

    Re: Acceleration problem

    jkordzi wrote:

    BillyC wrote:

    66 coupe 289, stock bottom end and heads, Edelbock performer carb and manifold, mechanical fuel pump, Pertronix ignition and coil (resister wire removed). T5 trans. My problem is when I accelerate aggressively (not floored) the motor cuts out for a split second then continues to run fine. When I say a split second I mean it sounded like something broke the first time it happend but I tried it again watching the tach and the revs dipped momentarily. Sometimes it will miss several times at around 3000 rpm when I'm accelerating fairly hard. Driving normally it runs perfect. But driving "normal" ain't no fun.

    If this issues started after you installed the carb, then that's where I'd look.  Does it only happen at specific RPM?  Only under a fairly hard acceleration, or anytime you get to that RPM?

     
    Carbs been on the car for years. Haven't changed anything recently. I'm thinking the ethanol gas has finally taken its toll.

    "anyone that stops learning is old, whether at twenty or eighty"Henry Ford
       •Thread Starter
     

    4/10/2015 9:10 PM  #12

    jkordzi
    I FYI 24-7

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    From: Sequim, WA
    Registered: 12/28/2013
    Posts: 927

    Re: Acceleration problem

    BillyC wrote:

    jkordzi wrote:

    BillyC wrote:

    66 coupe 289, stock bottom end and heads, Edelbock performer carb and manifold, mechanical fuel pump, Pertronix ignition and coil (resister wire removed). T5 trans. My problem is when I accelerate aggressively (not floored) the motor cuts out for a split second then continues to run fine. When I say a split second I mean it sounded like something broke the first time it happend but I tried it again watching the tach and the revs dipped momentarily. Sometimes it will miss several times at around 3000 rpm when I'm accelerating fairly hard. Driving normally it runs perfect. But driving "normal" ain't no fun.

    If this issues started after you installed the carb, then that's where I'd look.  Does it only happen at specific RPM?  Only under a fairly hard acceleration, or anytime you get to that RPM?

     
    Carbs been on the car for years. Haven't changed anything recently. I'm thinking the ethanol gas has finally taken its toll.

    I doubt it.  I'm thinking it's the ignition.  Can you remove the petronix and put in a set of points, or install another distributor?
     

    Cheap, Fast, Good:  Pick Any Two
     

    4/10/2015 9:32 PM  #13

    True74yamaha
    Senior 24-7 FYI Addict

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    From: Salt Lake City
    Registered: 5/07/2013
    Posts: 2,529

    Re: Acceleration problem

    Those carbs are known for float problems. I had that same issues on my 65 289.

     

     

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