---------------------------------------------------------- RotaxEngines-List Digest Archive --- Total Messages Posted Thu 01/29/09: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 02:47 AM - Re: 914 w/intercooler induction air heating (Robert C Harrison) 2. 04:14 AM - Re: rotax 912 over-run experience (K Dilks) 3. 06:55 AM - Re: rotax 912 over-run experience (rampil) 4. 07:21 AM - Re: rotax 912 over-run experience (Roger Lee) ________________________________ Message 1 _____________________________________ Time: 02:47:46 AM PST US From: "Robert C Harrison" Subject: RE: RotaxEngines-List: 914 w/intercooler induction air heating Hi! Gilles. Happy New Year ...if not too late ! I was concerned about carb. ice with an intercooler fitted to my 914 installation. Especially when the Intercooler manufacturers (Bell) were claiming 25deg temp drop in Winter and 20deg drop in Summer. I have a crude temperature sensor reduxed into a plastic hollow tube to the port carb throat and have never seen less than 6 deg Celsius. Even descending on low power settings through thin cloud formation from 10,000ft after the wind screen in my Europa began to frost over on the inside with minimal cabin heat facility. Whilst I do understand that carb ice conditions are very humidity and ambient temperature connected this has left me "fairly" confident that ice is not an issue ( I am reluctant to actually say that since next flight ..!) However Rotax do recommend a carb heat facility even with a turbo fitted =85but this may be sales justified or more appropriate to tropical applications in real terms. My air filter is not of the air box type just a simple washable air canister clipped to the turbo intake. Regards Bob Harrison G-PTAG Europa Kit 337 Now with Rotax 914. -----Original Message----- From: owner-rotaxengines-list-server@matronics.com [mailto:owner-rotaxengines-list-server@matronics.com] On Behalf Of Gilles Thesee Sent: 28 January 2009 21:54 Subject: Re: RotaxEngines-List: 914 w/intercooler induction air heating Patrick and all, > I am searching for some info on the temperature difference between airbox temperature and ambient during flight. JAR 23.1093 states if the temperature rise is more than 56 deg C when ambient temperature is -1 deg C at 60 % power there is no need for carb heating. In JAR-VLA 1093 the temperature rise should be 38 deg C with the same conditions. Has anyone with a 914 w/intercooler done some flight tests? Installing carb heating is a bit of a hassle so Remember those rules have been written by people used to Lyco/Conti aircooled engines, with hot air as the sole means of avoiding carb ice. We are flying an MCR 4s with an intercooled 914. Due to our engine installation peculiarities, our carb temperatures are within the 40-50=B0C range in flight. Whatever the air temperature, remember ice cannot build up on warm metal. But it all depends on your particular engine installation. With a proper airbox around the air filter, it is no big deal to devise a warm air door into the engine compartment. FWIW, Best regards, -- Gilles http://contrails.free.fr ________________________________ Message 2 _____________________________________ Time: 04:14:47 AM PST US Subject: RotaxEngines-List: Re: rotax 912 over-run experience From: "K Dilks" Its called over speed . Above 6100 and with good oil pressure there is a good chance you have had valve to piston contact. Compression check and lift all the cylinder heads. Inlet valves and pushrods are not cheap. Why do you over speed? The limits are not there for you to pick and choose when you follow them! -------- Austria ............. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=227465#227465 ________________________________ Message 3 _____________________________________ Time: 06:55:29 AM PST US Subject: RotaxEngines-List: Re: rotax 912 over-run experience From: "rampil" RPM over 5800 can cause valve float where the cylinder valve springs are basically not strong enough to keep up with the high frequency. Then you can get the valves smashed up and the piston deformed and lifters crushed. If you value your aircraft, why don't you believe the owner's manual for the engine. -------- Ira N224XS Read this topic online here: http://forums.matronics.com/viewtopic.php?p=227488#227488 ________________________________ Message 4 _____________________________________ Time: 07:21:50 AM PST US Subject: RotaxEngines-List: Re: rotax 912 over-run experience From: "Roger Lee" Hi Nicola, You most likely have damaged a valve seat, lifter or bent a rod. It needs to have the heads pulled to inspect the valve seats, lifters and pull the rods to look to see if they are straight. Don't just leave this and keep flying as you will incur further damage. -------- Roger Lee Tucson, Az. Light Sport Repairman - Maintenance Rated Rotax Service Center 520-574-1080 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=227491#227491 ------------------------------------------------------------------------------------- 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.