Thanks for sharing that, I will now go check on mine!
--- In [email protected], Mike Willis <m...@...> wrote: > > Hi everyone, > > The same day Linda ended up in a field in the US, I had to make a > precautionary¹ landing in the UK due to severe loss of power and rough > running. This happened about 30 minutes into a flight in my Alon A2. > > I had decided to climb from 2,000 to 2,500 feet, applied full power and my > sweet running engine suddenly ran very roughly. After finding that > application of carb. heat made the situation much worse, and not seeing any > other immediate problem I looked for somewhere to land. I could just hold > altitude at 70 mph and by luck there was a nearby farm strip on which I > successfully landed. On throttling back in the flare the engine stopped. > > After pushing the aircraft off the strip I tried cranking with the mags off > to check the engine was free, and we heard a sticking or hissing noise. > Hand turning the prop seemed to indicate the compressions were fine and we > could see nothing leaking, dripping or broken. > > Today I went to the farm strip with my engineer. He found the problem in > around one minute (the time it took to open the left cowling plus 10 > seconds) and another minute to repair. > > There is an induction pipe - a metal tube - connecting the carburettor to > each cylinder inlet. The inlet manifold flange on the cylinder is larger > than the pipe, so there is a short rubber sleeve slipped over the pipe to > match the diameter and then a longer and larger diameter rubber sleeve > fitting over both to form the seal. These are held in place with two hose > clips. > > The lower of the hose clips on the rear port cylinder induction pipe was > loose and the rubber spacer that side had slipped down the pipe. This meant > that there was no mixture to that cylinder it was sucking air - and it > would also imbalance the mixture to the other cylinders. This accounted for > the sudden power loss and rough running. > > Therefore the various theories such as carb. icing, stuck inlet valve and > cracked piston were all wrong, and a precautionary landing was definitely > required. The engineer did a thorough inspection and ground check of the > engine, and then I flew it away. > > So check those hose clips for tightness once in a while, and may it never > happen to you! > > Best regards, > > Mike > > m...@... > www.ercoupe.co.uk > > Alon A2 Aircoupe > A-188 > G-HARY > -- >
