Engine won't start after sitting for three years

Off the top of my head, gummed up needle valves and/or glowplug.

Three years, huh? Take the engine apart completely. Soak the parts in fresh fuel and scrub with a toothbrush to remove old fuel residue. Be sure both needle valve seats are free of blockage. Install a new glow plug. Readjust both valves and it should run.

Keep us posted.

Dr.1 Driver "There's a Hun in the sun!"

Try a new glo-plug. OS#8. Also make sure that your glo-plug battery is putting out a full charge. If that doesn't work then you might try taking it apart and cleaning it but I doubt that is going to make any difference 'cause you say that it ran fine once you got it started. You should do all this on the bench and that will eliminate any glitches in the A/C fuel plumbing. At any rate, once you get a little fuel on the top of the cylinder (even by pulling the plug and squirting a bit it) you should get a real kick when you try turning the prop with a chicken stick. That is a pretty good indication that the plug and battery are good. Gord Schindler MAAC6694

Also take apart the tank and replace the klunk tube along with the other silicone tubing. Check the brass lines for cracks and make sure the fuel tank plug has not dried up and cracked, allowing in air.