pony motor timing

There is a hole below the mag on the engine side with a pipe plug in it. Remove it and look for a mark with a letter on the flywheel. "G" I think can't remember.

Line up the M on the mark in the mag with the rotor pointing at # 1. the piston should be on the compression stroke and your done.

I'd pull the carb, take it to the workbench, clean it thoroughly with gum-out or similar carb cleaning solvent. I'm thinking its a Zenith downdraft type like mine, you can find parts for them I believe, usually a cleaning will suffice, but you may need new gaskets, Zenith has a website ( link below )

Look at it closely, you might be able to find the leak, fill the bowl on the bench, not sure with this particular carb, maybe the needle seat ? Use extreme caution when doing this with gasoline, and using solvents as they are very combustible and have harsh vapors, best to fool with it outside in the open air, you don't want to concentrate gas/solvent fumes inside.

There is a typical cause for these to leak down, have read that the D-2's & 4's were more prone for this to occur, this is why we're always told to run the pony out of gas, by shutting the valve on the fuel line after the main engine fires up. I take it one step further by draining the gas out of the bowl, as the pony will run awhile before it runs out of fuel, mine has a drain plug, which I replaced with a petcock & short hose to make it easier, and by all means be very careful with gasoline & solvents no matter what you are doing.

• Zenith Fuel Systems

I had a similar dilemma on a D-7,( different starting engine) The book said to line up the mark on the flywheel gear, to the mark on the case, with the #1 piston up ( compression stroke, I put a cork in the plug hole to make sure, it'll pop out under compression. What I had to figure out was that when installing the magneto, after doing the above, to make sure the mag was winding up to fire a spark when the #1 piston was up,( if you wind the mag it will feel spring loaded, get harder to turn, then snap over, firing a spark). After thinking it out, I made sure I lined up the piston like I said above, then lined up the coupling on the end of the mag to the to pony, knowing it's set to spark when it turns just a little more, ( I turned back the mark on the flywheel to make sure the mag coupled with the pony & was set to spark when the mark lined with the mark on the case ). Once I did the this, it was in the right sequence and it started right up.

I'm not sure how mag timing on a D-2 is similar or disimiliar to the 2 cyl. vertical pony on a D-7. I know yours is the horizontally opposed cylinder type, may be different, so I know I'm comparing apples & oranges, but seeing no one responded, just trying to help.

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