Good Evening. I had a rather rough time at my field this afternoon, with two flame-outs on my trusty OS .61 SF. The engine is in a Hobbistar, which has been my primary plane since last September. The first time the engine flamed out, I ended up gliding the plane into a gully just beyond the runway. When I got to it, I noticed that the fuel pressure line had come off the muffler, so I figured it must have been the loss of back pressure, upon the line coming off the muffler, which caused the flame-out. (I found that the glow plug was still intact and functional.) Since I noticed the pressure line now easily came off the nipple, I snipped off 1/4 inch of the line and put it back onto the nipple. The next flight was even worse than the first. I noticed a change in the tone of the engine exhaust, and I thought I saw something shiny fall off the plane in flight. I wasn't sure at the time what exactly it was, but I would eventually find out! Once again, the engine ran erratically, so my first thought was, I better get it down. The engine dead-sticked a second time, but this time I was able to land it on the runway. When I got to the plane, I noticed the muffler was gone!!! I immediately called my LHS, and the good people there have put in a special order for a new muffler for the engine. It should arrive sometime next week.
This adventure got me wondering if silicone nitro fuel lines have a finite life span. Since I have been using the same two lines (supply and pressure) on this plane for about 10 months now, should I consider replacing them with fresh tubes? Please let me know your thoughts.
Thanks, Harry Sanchez