In an earlier posting today I mentioned a separate fuel injection setup for the Cirrus that was revealed to us by a former TCM engineer. This individual was contacted when we learned of the overheated cylinders in N142CD. I spoke with him on the phone today for a clarification of what I thought had been said, and he made clear to me that this setup procedure is known to Cirrus and that they use it. This was not quite the same as what I heard 48 hours ago but I admit that something may have been lost in the
note taking. I now seriously doubt that the problems in this engine were caused by an incorrect fuel injection setup.
Compounding this doubt is that I queried him about the altitude compensation system in the fuel injection pump. We felt it was not working properly, if at all, on the flight out. Specifically, I asked why we got 17 gph fuel flow on takeoff from an airport at 6000 feet msl. His calculations revealed that the system should have automatically reduced full throttle fuel flow to 15 gph at that altitude. So if anything, the setup was too rich and not too lean.
What was the cause of the problem? It certainly was not caused by anything that occurred on our 12 hour flight from Duluth to Hayward. Other than that, your guess is as good as mine.
What matters most is that Cirrus did the right thing by insisting that the engine be replaced. It will be installed by a Cirrus tech and initially flown by a Cirrus pilot before being released to Rob Leach for the ferry (after compression check, oil change, filter inspection, etc.) I was impressed by our factory tour, by the flight to Hayward and by the eventual success of Cirrus in demanding a new engine. Although the Grumman Tiger has been my choice for 22 years, I think all of you folks have a winner in this airplane and in its manufacturer.