My 140L has been running good all season. All of a sudden, not so good! First flight of the day the engine runs normal. Second flight it will act as if it is loading up and eventually clear up, but will load up again before I can get it in the air. I've started going through plugs often finding the plug element very black.

High end needle 1.25 out, low end not quite one turn. Regulator is set slightly below flush.

Powermaster DZ30 fuel
APC 16x11 prop
OSF plug.

Any suggestion would be greatly appreciated.

Thanks,
Todd

Did you just switch to a new can of fuel? Might be the problem if this started suddenly. If not, suspect something coming apart in the engine and putting aluminum deposits on the plug element.

Dave,

About a month ago, this problem showed up just after cracking open a new can of fuel. I ordered new fuel (new order came with the same batch # as the suspect gallon) and got along good with a couple of gallons, but now having the same problem. The engine has maybe 25 gallons through it by now.
I'm going to try Cool Power heli 30 today and see what happens.

Thanks,
Todd

Dave,

The Cool Power seemed to solve the problem. Burnt almost a gallon this afternoon and not a hiccup out of the engine. I pulled the plug and the coil is clean.

Todd Schmidt

Then bad fuel was the culprit.

Thanks for getting back to us. You should contact Powermaster and inform them. They are good people and need to know.