---------------------------------------------------------- RotaxEngines-List Digest Archive --- Total Messages Posted Tue 12/29/09: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 10:04 AM - Rotax 914 Won't Start (AmphibFlyer) 2. 02:42 PM - Re: Rotax 914 Won't Start (FLYaDIVE) 3. 03:58 PM - Re: Rotax 914 Won't Start (AmphibFlyer) 4. 04:26 PM - Re: Rotax 914 Won't Start (lucien) ________________________________ Message 1 _____________________________________ Time: 10:04:28 AM PST US Subject: RotaxEngines-List: Rotax 914 Won't Start From: "AmphibFlyer" A friend's Rotax 914 won't start--actually, it fires up, but won't get above about 900 rpm. When the weather was warm, the engine started and ran smoothly. But had trouble getting past 900 rpm on the last successful start, when the weather was starting to get cold. And now it just won't do it at all. I have a theory, but before mentioning it to the owner, I'd like to ask what you guys think is the cause. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=279115#279115 ________________________________ Message 2 _____________________________________ Time: 02:42:17 PM PST US Subject: Re: RotaxEngines-List: Rotax 914 Won't Start From: FLYaDIVE SeaRay: Ya gots to be more exact. What OAT? How long has the engine soaked at cold temps? What OIL? What viscosity oil? Is the fuel fresh? >From what you say ... It DID get above 900 RPM just took a long time to get the engine warm? Did you PRE-HEAT the engine? Sure sounds like PRE-HEAT should of been the first step. A fellow I know NEVER used pre-heat on his O-360 and the engine ran fine for many a year. He just had the engine rebuilt - TBO ya know. This being the first winter with the new engine (less than 25 hrs) the old no pre-heat procedure DID NOT WORK. It would not even turn over. Starter froze engaged. YET! As soon as the temps got to 50 F the thing kicked over in one blade. So, what theory do you have? Barry On Tue, Dec 29, 2009 at 1:03 PM, AmphibFlyer < SeaRey@abstractconcreteworks.com> wrote: > > > A friend's Rotax 914 won't start--actually, it fires up, but won't get > above about 900 rpm. > > When the weather was warm, the engine started and ran smoothly. But had > trouble getting past 900 rpm on the last successful start, when the weather > was starting to get cold. And now it just won't do it at all. > > I have a theory, but before mentioning it to the owner, I'd like to ask > what you guys think is the cause. > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=279115#279115 > > ________________________________ Message 3 _____________________________________ Time: 03:58:27 PM PST US Subject: RotaxEngines-List: Re: Rotax 914 Won't Start From: "AmphibFlyer" flyadive(at)gmail.com wrote: > > From what you say ... It DID get above 900 RPM just took a long time to get the engine warm? Nope, it didn't get above 900 rpm. It maxed out there and wouldn't accelerate even to normal idle speed. The last time it ran normally, the OAT was about 60 F. It had trouble getting past 900, but did after several seconds of chugging. At 45 F it would fire on all cylinders but couldn't break 900 rpm (approximately). I didn't pre-heat the engine, but I'm sure that low temperature is not the problem; it just makes the problem worse. These engines start just fine down to 0 F and below if the spark plug gaps are correct (.024, or less), which they were on this engine. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=279149#279149 ________________________________ Message 4 _____________________________________ Time: 04:26:44 PM PST US Subject: RotaxEngines-List: Re: Rotax 914 Won't Start From: "lucien" AmphibFlyer wrote: > > flyadive(at)gmail.com wrote: > > > > From what you say ... It DID get above 900 RPM just took a long time to get the engine warm? > > Nope, it didn't get above 900 rpm. It maxed out there and wouldn't accelerate even to normal idle speed. > > The last time it ran normally, the OAT was about 60 F. It had trouble getting past 900, but did after several seconds of chugging. At 45 F it would fire on all cylinders but couldn't break 900 rpm (approximately). I didn't pre-heat the engine, but I'm sure that low temperature is not the problem; it just makes the problem worse. These engines start just fine down to 0 F and below if the spark plug gaps are correct (.024, or less), which they were on this engine. Don't know if 2-stroke experience crosses over here, but two things that I've seen cause this kind of behavior are - huge, massively heavy prop - weak gearbox springs It always amazes me the gigantic 2 ton props a lot of guys hang on these things - what prop, how big and how many blades? If it's way past the MOI limit on the 912 GB (6000 kg/cm3 last I looked in the manual, same as the 2-stroke C box) the engine simply may not be able to overcome it. Same if the springs are worn and the preload is too weak. It'll be fighting the gearbox in that case too. All that could be aggravated by a cold start as well... If it's not that, I'm out of ideas and would like to know what it is once you finally figure out what it is... LS -------- LS Titan II SS Read this topic online here: http://forums.matronics.com/viewtopic.php?p=279154#279154 ------------------------------------------------------------------------------------- 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.