---------------------------------------------------------- RotaxEngines-List Digest Archive --- Total Messages Posted Tue 06/26/07: 5 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:03 AM - Re: 912 starting problems (Peter Jeffers) 2. 03:49 AM - Re: egt temp (Thom Riddle) 3. 04:05 AM - Re: 912 starting problems (Thom Riddle) 4. 05:09 AM - Re: RotaxEngines-List Digest: 4 Msgs - 06/25/07 (Noel Loveys) 5. 05:15 AM - 912 starting problems (Noel Loveys) ________________________________ Message 1 _____________________________________ Time: 12:03:09 AM PST US From: "Peter Jeffers" Subject: RE: RotaxEngines-List: 912 starting problems Hi Mark Probably a slipping sprag clutch. Quite a common problem with older 912=92s. There is also a modified larger starter motor available from Rotax which will prevent future problems with the clutch. Just a thought!! Pete Jeffers _____ From: owner-rotaxengines-list-server@matronics.com [mailto:owner-rotaxengines-list-server@matronics.com] On Behalf Of markdonahue Sent: 26 June 2007 06:24 Subject: RotaxEngines-List: 912 starting problems Kitfox model IV with a 912 UL Does anyone have some thoughts for me as to how to make my engine start more easily. Engine runs fine after starting. Battery is good and turns over briskly. Choke pulls to the stop. Throttle on idle. Have checked carbs and jets all are clean and all seems clear. If I add a bit of gas at the filter it will fire. Seems like its carb related. Spark seems weak, but have changed ignition wires and no change. And again it runs strong. I have had the carbs rebuilt at Lockwood, but that was 3 years ago, but it didnt seem to make any difference. Any thoughts anyone. I have 790 hours on the engine. Mark Donahue "http://www.matronics.com/Navigator?RotaxEngines-List"http://www.matronic s.c om/Navigator?RotaxEngines-List "http://forums.matronics.com"http://forums.matronics.com 24/06/2007 08:33 24/06/2007 08:33 ________________________________ Message 2 _____________________________________ Time: 03:49:40 AM PST US From: Thom Riddle Subject: Re: RotaxEngines-List: egt temp Noel, .....When the engine is running lean you will notice more than an increase in EGT reading. You can get a drop in power and sometimes even a bit of back firing. This will also happen when it's past time to refuel.,,,, Can you elaborate on these statements? I don't understand how running lean can cause backfiring or what it has to do with being "past time to refuel". Not being argumentative, just trying to understand what you mean and how this happens. Perhaps you should begin with your definition of backfiring and quantify "past time to refuel". Thom in Buffalo ________________________________ Message 3 _____________________________________ Time: 04:05:57 AM PST US From: Thom Riddle Subject: Re: RotaxEngines-List: 912 starting problems Mark, To get a better idea of what you are experiencing, and a basis for diagnosing the hard starting problem, please let us know exactly how you do your start procedure and whether it is hard staring when the engine is cold or hot etc. What is the idle speed of the engine when warm? Without observing and getting hands on we would need to know countless little details to make an intelligent guess at what is the cause of the problem. I was called in to fix the hot starting problem on a Katana with 912F engine AFTER the Diamond distributer "fixed" the problem with a new battery. I removed, disassembled, cleaned and inspected both carburetors. This aircraft had over two thousand hours on it and I did not see any entry in the logbook that the engine had been overhauled, nor any entry about carburetor overhaul. It turned out that one of the carbs had a starting jet that was too lean and the other had one that was too rich, the o-rings in a couple places were brittle and cracked, and there was a bad gasket on one of the starting carbs (enricher). We replaced jets with proper ones and replaced o-rings and gaskets. Put it all back together, did a mechanical and pneumatic synch with proper idle speed adjustment and problem solved. My point in telling this story is that your problem could be a simple single thing like incorrect starting procedure or idle speed adjustment, or it could be multiple problems that will need attention. Where are you located? Thom in Buffalo ________________________________ Message 4 _____________________________________ Time: 05:09:38 AM PST US From: "Noel Loveys" Subject: RotaxEngines-List: RE: RotaxEngines-List Digest: 4 Msgs - 06/25/07 P51s were built to be used in the European theatre with Rolls-Royce engines. That could be the reason for the Celsius gauges. Noel > Time: 03:30:26 AM PST US > From: Gilles Thesee > Subject: Re: RotaxEngines-List: Re: Rotax 912 Cooling issue / > Zodiac CH 601 HDS > > > > Hi Giles, > > > > Your right about the temps if he said they were Celcius, > but he said they were > F. Most of us here in the US run our gages in F, but you > have the option of > using C on a lot of gage sets. > > > > Here is an easy, do it in your head, formula for converting C to F. > > > > Roger, > > Thank you for your message. > Yes the temps in question were said to be F, but as they did > not seem to > make sense, the possibility of a unit confusion came to my mind. > > Re the tip on conversion, as European flyers, we are used to convert > when dealing with engines from across the pond (though we usuallly do > convert from F to C). > Funnily, in P51 field manuals, the engine temps were in > Celsius during WWII. > > Best regards, > -- > Gilles > http://contrails.free.fr ________________________________ Message 5 _____________________________________ Time: 05:15:26 AM PST US From: "Noel Loveys" Subject: RotaxEngines-List: 912 starting problems I'm not too sure about the carburettor on the 912. If it is one of the side draft Bing type carbs with the moving main jet than the choke is a bit of a misnomer on that setup. What is commonly referred to is in fact an enrichener which allows extra fuel to enter the throat of the carb at low rpm. You may find adding a primer, that gives a squirt of gas down the throat of the carb before starting, may make starting a lot easier for you. Noel > Time: 10:25:09 PM PST US > From: "markdonahue" > Subject: RotaxEngines-List: 912 starting problems > > Kitfox model IV with a 912 UL > Does anyone have some thoughts for me as to how to make my > engine start more > easily. > Engine runs fine after starting. Battery is good and turns > over briskly. > Choke pulls to the stop. Throttle on idle. Have checked > carbs and jets all > are clean and all seems clear. If I add a bit of gas at the > filter it will > fire. Seems like its carb related. Spark seems weak, but > have changed > ignition wires and no change. And again it runs strong. I > have had the > carbs rebuilt at Lockwood, but that was 3 years ago, but it > didnt seem to > make any difference. Any thoughts anyone. > I have 790 hours on the engine. > Mark Donahue ------------------------------------------------------------------------------------- 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.