Engine Cutting Out

[Paul Bianchi]

I can't get my OC-3 to run for more than 30 seconds before cutting out.  I suspected fuel so I disconnected the gas line and I have plenty flow and my the fuel in my bowl is clean.  I disassembled and cleaned the carburetor (marvel schebler), checked the float level and it was set to 1/4" as specified.  When I remounted the carburetor it started right up but it continues to cut out. It will start back up but dies again.  I guess I'll move onto spark tomorrow...

[oliverchris]

You're right to check the fuel line first...one idea. There may be a layer of water underneath the gasoline in the sediment bowl and/or tank. I've seen that happen with the same symptoms.

[Paul Bianchi]

I went out this morning and started checking the electrical.  I pulled my rotor cap off to check the points and found that the rotor mounting bracket had snapped off.  It looks like a few rotor teeth snapped off the rotor and probably lodged in the next gear tooth and through the rotor off axis snapping off the mount.  Prior I had observed a slight wobble in the rotor when I looked in the timing window of the magneto but didn't think much of it..  How it ever ran with a broken rotor mount is beyond me.

After I bolted on my back-up magneto the engine started right up so I thought I had the problem solved.  Well about 30 seconds later the engine cut out again.  Frustrated I cleaned up and went in for lunch. I saw Chris's post about possible water in the fuel so after lunch I took the fuel tank off and drained it completely.  Put clean fuel back in it and it started right up again and kept on running this time.  I hooked up my new purchase (an old IH ground driven potato digger) and dug a few rows of potatoes.  Chris, we were both on the right track FUEL!  Thanks for the help!