Hi Dave

I have a 140DZ that behaved strange the last time I flew it. It was hard to start
and while cranking it with the starter, it seemed to blow air back to the tank instead of sucking fuel into the pump. I finally got it started by blowing into the overflow line at the fuel tank. It then ran lean and had to be richened by 1/4 turn compared to the normal setting. Open throttle was then Ok but midrange still lean. Idle Ok.

I suspect the pump... Is it any parts in the pump that usually fail ? I hesitate to send the engine in as I live in Norway and would rather change suspected parts in the pump myself.

Oistein