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Barely start - air leak

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Kasperwing1:
My engine was only half-way through break-in period then sat for three years. Before installing, I performed a leak-down test. It didn't drop at all in two hours. My engine has inverted installation. Was advised to spray atomized lubricant through the intake with the spark plugs removed to lube the pistons and cylinders. I used BLASTER MULTI MAX for this. With exhaust manifold off I could see the inside had a light film. Since the plugs are on the bottom and can flood easily, my first start I only used LIQUIDO starting fluid, then opened my fuel shutoff. The fuel was half a year old, 86 octane, Ethanol Free mixed with Bluemax 2 cycle aviation oil (mineral oil) then later added VP Racing OCTANIUM MADDITIVE Octane Concentrate. I barely got it started during two different times, 1000 RPM for only 10-20 seconds each, then would die. I replaced the fuel with fresh 91 octane with the same mineral oil. Same thing, maybe slightly higher idle. I re-checked torque on the manifold bolts and head bolts. I performed another leak-down test. It's dropping 2 PSI in 10 minutes. Installed I can only spray about half the engine but did not see any bubbles at the PTO seal or anywhere else I could spray. Does anyone know if the above mentioned chemicals would hurt the seals? I found a 1940 Abstract online saying mineral oil will cause swelling of synthetic rubber, such as Neoprene, Thiokol and Perbunan. I don't know if these original seals are synthetic or natural. Any smart people here?

Interceptor398:
LOL,  many smart people hear-----if your spark plugs are pointed up!   Try some water and dish soap mix to track down the leak.  Might take some effort but the air is getting out someplace.  I do not know about the chemical interactions of what you are using.

Kasperwing1:
Update-The air leak is gone. Probably in the test setup. I have cleaned the carburetor, changed to new high octane fuel, cut 3/8" off of rear ignition wire at spark plug cap. Normally, the forward cylinder is the only one working. If I leave the forward spark plug cap off the rear cylinder works, but they are a bit finicky trying to start on one cylinder. With a cap off, the engine will only hit 4650 RPM. I took a video of the two spark plugs firing outside the engine today. I need to put the video where I can slow it down, the starter cranks at 1000 RPM and looks like both plugs are firing the same time. One plug should fire 180 degrees after the other. My Owner's Manual theory only explains single cylinder. There must be a component in the magneto, coil, or somewhere else that puts the spark on the second plug 180 degrees later. Anyone know what this is called and where it's located? Also, I'm unable to pull the spark plug wires off of the coil. Are these ever hard mounted into the coil? After I slid the sleeve away from the coil, several times I pulled 40 pounds and it didn't budge. The forward cap is real simple with the inside composed of a bent uninsulated splice, which doesn't positively snap onto the spark plug. The rear cap says NGK, is 5000 ohms and provides a little brighter spark that doesn't fade out as quickly as the forward one. Each spark plug, without changing position on the coil, will run either cylinder if I leave the other cap off.

Interceptor398:
I've never had the wires off a coil but I do think they are hard mounted.

mswyka:
I will second the comment on the spark plug wires.  If there is a problem with the coil, my sense is that it is best to get a new one.  The NGK caps have worked well for us when we have not had an original working coil/end cap combination.  I have the number for the cap that I have used somewhere and will post it if I can find it.

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