-----Original Message----- From: robert gill Sent: Sunday, March 02, 2014 1:10 PM To: krnet at list.krnet.org Subject: Re: KR> flying, KR 19-8322
While I am, here how the hell do anyone tune a revflow carby I can tune the mix at the needle to run smooth at full throttle soon as i pull it back under about 80% and to idle, the engine sounds so rich it wants to drown! and have to continuously fumble between throttle and mix while flying.Some suggestions would be handy. Robert I don't have an answer to the question of the Revflow. I have been trying to get the one I have tuned to where it runs smoothly at all throttle settings, but still no luck. I have Joe at Revmaster sending another needle to try. If I get the top end OK it will stumble in the mid ranger, generally right at the RPM I would like to use in pattern. If I get it run well at midrange the top end is way to lean or rich. I bought another needle from Revmaster a few weeks ago that brought the top end mixture where it needed to be, but was so rich at part throttle that I had to bring the mixture almost to idle cutoff in pattern to keep the engine running. Also when tuning with the plane on the ground with the tail tied down and the cowl off, I get it to run pretty well playing with the needle adjustment, then run terrible with the cowl on and in flight. I did try a tilotson carb last week. It is a little large but worked good at high throttle settings but again would stumble in midrange, and sometimes at idle it will die with out warning. It will always restart with the choke on. I had rigged up a speedometer cable to control the main mixture needle. I wonder if the midrange stumble on both of these carbs is due to the large passages in the intake manifold? It has been cold and it seems to me that the fuel is falling out of the air stream at lower throttle settings and the cold manifolds. I remember reading something about this in a book on carburetor tuning I had read many years ago. On my old KR I was using the Zenith that Great Plains sells with a single runner manifold to the heads. That engine was also a 2180 cc. That combination work very well for many years. It ran smooth throughout the throttle range, summer or winter, idled well and was easy to start. The only thing I did not like about it was using a speedometer cable to control the mixture. I like the robustness of the hardware on the Revflow. I am going to try one more time with the new needle, but I am getting all the parts together to use the Zenith again. I want to fly the plane and not fixate so much on the carburetor. Right now I am afraid to go far from the airport. Of coarse I will have to do some glass work on the cowling to make the Zenith fit and come up with a mixture control for it, because it needs to hang lower under the engine. _______________________________________________ Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org please see other KRnet info at http://www.krnet.org/info.html see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change options