Jeff York via KRnet wrote:
I think I am also going to buy the RevFlow floatless carb in 34 mm size.
I recall Jim Hill flying behind what I remember was a RevFlow, but it could have been something else. It worked fine, but Jim decided to feed it ram air to improve performance a bit, so he redid the cowling a bit and provide ram air down the carb throat (as one would naturally do). He took off, went into a climbing turn to down wind to circle the airport, and the engine suddenly quit! He was able to complete the loop and come back to the same runway he departed on, but there were some very tall trees right at the end of the runway.
The adjacent landowner refused to cut the trees due to some feud with the airport board, so the airport was a "one-way" runway....you had to take off to the west, and land from the west, with only 2500' of 40' wide runway. Jim had to land over the tall trees, and burned 90% of the runway trying to get it on the ground, then ran off the end and about 200 yards into a plowed field before hitting a drainage ditch, which resulted in a nose-over that broke the whole tail of the plane off, just ahead of the empennage.
The best explanation we could come up with for that was that apparently the ram air pressure over-powered the head pressure of the fuel tank (or reduced it considerably) and reduced fuel flow to the carb, and it quit. It ran fine on the ground...after another prop was installed. Ram air was removed, and no more problem. I'm not saying there's a problem with the RevFlo, or that the carb I'm talking about even a RevFlo....that was a long time ago, but whatever carb you use, read the directions and pay particular attention to air inlet and intake parts.....it really matters!
As for the Ellison, the installation manual goes into lots of detail regarding the air inlet path, as well as ensuring that the carburetor is not subjected to high temperatures or exhaust radiation. I'll dig that up and post it later today.
If you want to see what Jim Hill's plane looked like after the repairs, see http://www.n56ml.com/jhill.html . Since the tail was broken he turned it into a KR2S, using the NACA tail surfaces that are included in the "new airfoil" drawings, and it looked pretty good. He sold it to somebody in Pine Bluff, OK, if I remember correctly, to fund the engine for the Sportsman he was buying. Note that his engine is a single port VW.
The photos at the website above were taken in Jim's hangar, which I now own (after his sudden death), but it's a LOT more cluttered now than when Jim owned it!
Mark Langford m...@n56ml.com http://www.n56ml.com Huntsville, AL -- KRnet mailing list KRnet@list.krnet.org https://list.krnet.org/mailman/listinfo/krnet
