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Thread: D4 pony motor throttle adjustment

  1. #1
    Join Date
    Mar 2019
    Location
    Salem, Oregon USA
    Posts
    25

    Default D4 pony motor throttle adjustment

    Hey folks! So I've did a complete pony carb rebuild, and cleaned fuel lines, new plugs.etc, and the pony motor started for the first time in 19 years! After it started I noticed that there was no way to control the throttle with the pull handle. It was at full throttle and I couldn't idle it down. After doing some troubleshooting it looks like there is a big gap between the throttle control and the "rest". Looks like I did a wrong install, or something that doesn't let it idle down.
    20190519_100034.jpg
    20190519_100038.jpg

    Is the carb arm upside down?

    Can you give me some advice on the proper way to fix this issue?
    Thanks

  2. #2
    Join Date
    Sep 2007
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    nw indiana, usa
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    1,407

    Default

    Without looking at 1 in the barn, i think u got a lever on the wrong side of the governor nub.
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  3. #3
    Join Date
    Nov 2006
    Location
    McBEE, SC
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    2,241

    Default

    Just walked out & snapped a pic20190519_135734.jpg the rod with the tang pointing up is the throttle rod.
    When you pull on the throttle knob the tang pulls the extended pin in the carb arm to the operator to slow down. All the way in against the stop is full speed ahead. It's hard to get a good look down in that dark hole in the daylight, if you need more the contrast will be better this evening.
    Last edited by STEPHEN; 05-19-2019 at 12:10 PM.
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  4. #4
    Join Date
    Mar 2019
    Location
    Salem, Oregon USA
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    Default

    Thank you for the advice and pictures. I will go now and try to get the rod on the other side of the tang. I've got it exposed again since I had to take the fuel tank and air breather intake off. See if that works.

  5. #5
    Join Date
    Mar 2019
    Location
    Salem, Oregon USA
    Posts
    25

    Default

    OK that looks like the reason. I am posting follow up pictures to show correct side to mount throttle control tang for pony motor carb. This fixed it so now the controls fully depressed shows low throttle/idle now.
    20190519_123923.jpg

    Here is a better picture a little more zoomed out to give perspective
    20190519_123946.jpg

    Back together again!
    20190519_130622.jpg

    Will fire it up and post in another thread soon. I'm pooped today, after cleanup. Thanks for the fast help today!
    Last edited by bexrex; 05-19-2019 at 03:38 PM.

  6. #6
    Join Date
    Nov 2006
    Location
    Pittsford NY
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    The throttle control rod tang is on the correct side of the carb throttle boss. Your throttle control rod is pushed all the way in in photos 1 and 2 meaning that the pony is under full governor authority and will run at the governed speed (i.e. full speed). If you pull the throttle control rod out, you are limiting the upper range of the governor. The further out you pull it, the further you reduce the governor control, and the slower the pony will run, until you pull the control rod all the way out and the pony will be at idle. In reality, not long after you start pulling the throttle control rod out towards idle, there is effectively no more governor control. When it's running fully governed with no load, you can check the distance between the tang and the boss and that's how far you can pull our the throttle rod before it starts taking effect.

    Start the pony with choke and throttle in the idle position. It has no oil pump and relies on splash lubrication so give it a change to get nicely lubed up before you open the governor up.
    If it does not idle, we can help with that. Mine starts from cold at an idle with full choke and takes about 20-30s before it'll run without choke. Then it'll idle all day long if I let it.
    Cheers,
    Neil.

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