---------------------------------------------------------- RotaxEngines-List Digest Archive --- Total Messages Posted Tue 09/05/17: 1 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 10:43 AM - Re: 912 fuel problems (Guy Buchanan) ________________________________ Message 1 _____________________________________ Time: 10:43:26 AM PST US Subject: Re: RotaxEngines-List: 912 fuel problems From: Guy Buchanan 75 hours over three years means auto fuel sat in the tank unused for some long periods. From what I've heard auto fuel only has about a two week shelf life. I worked on a Kitfox that had sat for long periods with auto fuel in its tanks, and the fuel left deposits in the tanks which, when re-filled, would soften and migrate to the filters, plugging them. It took only minutes for the filters to become plugged enough to kill the engine. The challenge was that you couldn't /see /the deposits, but you could sure feel it when you tried to drive fuel through them. Your two symptoms of requiring choke to run and inability to attain full rpm indicate a fuel flow problem, as you've already guessed and proven. If your tanks have become "varnished", you'll have to clean them thoroughly. On the Kitfox we rigged a fuel pump and circulated fuel through the tanks continuously for two weeks, replacing the cycled fuel daily, until the varnish was eliminated enough for it to run continuously. Guy Buchanan Ramona, CA Kitfox IV-1200 / 912-S / Warp 3cs / 600 hrs Glider pilot, too On 9/1/2017 7:37 AM, Henry Roden wrote: > > 1) Is this a normal throw for this cam? > 2) Why does it need so much choke when it did not do so before all the > fuel problems. > 3) Is there something else I am missing that would cause these symptoms? > Since pulling off the fuel pump off another mechanic remarked that the > engine seemed very stiff to pull over with the prop, it had always > been that way since new and I had attributed it to the engine gearbox > combination. I removed the top plugs and the gearbox and the engine > and the gearbox are each quite smooth but not when the gearbox is > mounted back on the engine. It feels like the plugs are still in and > there is compression pressure causing resistance? > I apologize for the long description. > Henry > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message rotaxengines-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/RotaxEngines-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/rotaxengines-list Browse Digests http://www.matronics.com/digest/rotaxengines-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.