---------------------------------------------------------- RotaxEngines-List Digest Archive --- Total Messages Posted Sun 07/27/08: 8 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:06 AM - 912 UL dieseling (Catz631@aol.com) 2. 08:42 AM - Re: Rotax 912 Ivo In Flight Adjustable Combo. (RockyRim) 3. 09:35 AM - Re: 912 UL dieseling () 4. 09:37 AM - Re: 912 UL dieseling (lucien) 5. 10:52 AM - Re: Changing Crush Gasket (Graham Singleton) 6. 12:48 PM - Re: Changing Crush Gasket (lucien) 7. 02:36 PM - Rotax oil pickup fitting at bottom of engine on 912 (Pete Christensen) 8. 09:51 PM - Re: Rotax oil pickup fitting at bottom of engine on 912 (Roger Lee) ________________________________ Message 1 _____________________________________ Time: 06:06:38 AM PST US From: Catz631@aol.com Subject: RotaxEngines-List: 912 UL dieseling I have a 912UL on my Kitfox and for the second time, it dieseled on shutdown. It went backwards aprox 3 revolutions. This time I was at a remote airport with no one there (totally locked up) It was about 94 degrees outside so I elected to fly the aircraft 20 minutes back to my home field. I know there is a possibility of injecting air into the lifters when this happens.(should purge the oil system) When I started the engine the oil pressure came up but there were some fluctuations in the pressure indications on my Westach gauge. This could have been air bubbles or normal oil pressure fluctuations in this hot southern weather.(as it does when hot at low rpm's) In any case I had smooth normal oil pressure at cruise. At my home field I changed the oil and checked the filter element for contamination. It looked fine. I am running a Rotax oil filter and it has a rubber diaphragm which I believe will prevent reverse oil flow.Wether this would prevent air entering the lifters, I don't know. Today I am going to do the lifter clearance check before further flight. I had been using 87 oct gas then switched to 89 after the first event. I am now going to use premium (93) in hopes of stopping this from happening again. The recent manual says I can use 87 on the 912UL (although my original 1994 manual says to use 97 or premium) Has anybody ever had this happen or am I the only one? I called Dean at Lockwood(the Rotax guru you see on the Lockwood DVD) and he said that he had never heard of this happening. The engine temperatures on shut down were perfectly normal. I know the timing on the engine is fixed, my idle is 2000. The only thing I can think of is fuel. Even my fuel was fresh midgrade. Total engine time is 175 hours. The engine is an early 1994 . Any opinions would be greatly appreciated! Dick Maddux Rotax 912UL Pensacola,Fl **************Get fantasy football with free live scoring. Sign up for FanHouse Fantasy Football today. (http://www.fanhouse.com/fantasyaffair?ncid=aolspr00050000000020) ________________________________ Message 2 _____________________________________ Time: 08:42:14 AM PST US Subject: RotaxEngines-List: Re: Rotax 912 Ivo In Flight Adjustable Combo. From: "RockyRim" Hugh: The rock guard tape from SRI comes on a roll, so you have to cut it to the shape you want instead of buying precut pieces from Warp drive or another supplier. Rocky Read this topic online here: http://forums.matronics.com/viewtopic.php?p=195201#195201 ________________________________ Message 3 _____________________________________ Time: 09:35:57 AM PST US Subject: Re: RotaxEngines-List: 912 UL dieseling From: Hi Dick "Any opinions would be greatly appreciated!" I had a 1972 Yamaha RT-2 360 that used to run on after shut down if it was real hot, I always used hi test fuel. As a matter of fact I once did a compression test and the cylinder fired! It only has 1 spark plug, it must have been hot glowing carbon somewhere in combustion chamber. On cycle it is easy to prevent just put in gear and drag clutch on shut off, but I would sometimes choke it for a few seconds before shut down, easy to try on 912. You may also want to have a very close look at spark plugs, are they the right heat range? Do they have excess carbon on them? Are you using thermal conductive compound on plug threads and are they torqued properly? Are you certain that your ignition ground is not intermittent? Is your alcohol level infuel whacked like 15% because distributor overmixed? Add 25% 100LL next hot day and see if that helps? Ron Parigoris ________________________________ Message 4 _____________________________________ Time: 09:37:17 AM PST US Subject: RotaxEngines-List: Re: 912 UL dieseling From: "lucien" [quote="Dick Maddux"]I have a 912UL on my Kitfox and for the second time, it dieseled on shutdown. It went backwards aprox 3 revolutions. This time I was at a remote airport with no one there (totally locked up) It was about 94 degrees outside so I elected to fly the aircraft 20 minutes back to my home field. I know there is a possibility of injecting air into the lifters when this happens.(should purge the oil system) When I started the engine the oil pressure came up but there were some fluctuations in the pressure indications on my Westach gauge. This could have been air bubbles or normal oil pressure fluctuations in this hot southern weather.(as it does when hot at low rpm's) In any case I had smooth normal oil pressure at cruise. At my home field I changed the oil and checked the filter element for contamination. It looked fine. I am running a Rotax oil filter and it has a rubber diaphragm which I believe will prevent reverse oil flow.Wether this would prevent air entering the lifters, I don't know. Today I am going to do the lifter clearance check before further flight. I had been using 87 oct gas then switched to 89 after the first event. I am now going to use premium (93) in hopes of stopping this from happening again. The recent manual says I can use 87 on the 912UL (although my original 1994 manual says to use 97 or premium) Has anybody ever had this happen or am I the only one? I called Dean at Lockwood(the Rotax guru you see on the Lockwood DVD) and he said that he had never heard of this happening. The engine temperatures on shut down were perfectly normal. I know the timing on the engine is fixed, my idle is 2000. The only thing I can think of is fuel. Even my fuel was fresh midgrade. Total engine time is 175 hours. The engine is an early 1994 . Any opinions would be greatly appreciated! Dick Maddux Rotax 912UL Pensacola,Fl Get fantasy football with free live scoring. Sign up for FanHouse Fantasy Football today (http://www.fanhouse.com/fantasyaffair?ncid=aolspr00050000000020). > [b] I had my 912ULS pop once on shutdown a while back (tho it didn't spin backwards). I've never had another instance of that happening before or since. The only variable that there could have been is the fuel - everything else, the weather, etc., was exactly the same as it had been many times before when there wasn't a proble. So, the fuel is my vote. There was another thread recently on ethanol and at the risk of dredging that up again..... I very seriously question the quality of the E10 gas - I did a "water test" on some local E10 yesterday and was shocked at the results. The gas remained thickly cloudy after mixing it up with the water, clearly indicating the presence of some other kind of contaminate. I tried some E10 from another station (this time 87 octane instead of 91) and got the exact same results with the water test. No way I'd want to run that stuff through my 20,000 dollar motor ;). So all that said...... try running some gas of known quality through the motor for a while. I.e. 100LL which doesn't have ethanol in it and also has a lower vapour pressure, and see if that doesn't cure the problem. I know the quality of gas is quite variable in my area, so I'm reasonably sure that's why I got the dieseling event I got..... LS -------- LS Titan II SS Read this topic online here: http://forums.matronics.com/viewtopic.php?p=195216#195216 ________________________________ Message 5 _____________________________________ Time: 10:52:31 AM PST US From: Graham Singleton Subject: Re: RotaxEngines-List: Changing Crush Gasket Paul Thilo is right, and there's another good reason for using new crush washers, this is not a drain plug and solid, it's a banjo bolt. Over torque it and it will stretch or break, also the barrel.will deform and no longer be flat. The crush washers are oval section so they easily deform when new to form a seal. It takes too much torque to deform them when they are already crushed. Not wise to try and vent a well designed wheel ;-) Graham Thilo Kind wrote: > > Hi Paul, > > I admit, that in a car both the safety-wiring of the bolt and the > replacement of the crush washer could be overkill worst that can > happen to you is that the car stops at the shoulder of the raod. In an > airplane, this is an entirely different story Thats why all the > manufacturers as well as the FAA recommend / insist on those measures. > It is definetly not a money making deal of manufacturers they are > not make a lot of money on a piece of safety wire and a copper washer. > > Thilo Kind > > ------------------------------------------------------------------------ > > *From:* owner-rotaxengines-list-server@matronics.com > [mailto:owner-rotaxengines-list-server@matronics.com] *On Behalf Of > *paul wilson > *Sent:* Sonntag, 27. Juli 2008 03:31 > *To:* rotaxengines-list@matronics.com > *Subject:* RE: RotaxEngines-List: Changing Crush Gasket > > You are repeating what all manufacturers say. In the real world its no > big deal. Our race trucks seldom get a new washer and when we do its > never copper its dead soft aluminum. Never had a leak an never heard > of the bolt falling out. Been doing this to many years and so we know > its no sweat. Bolts fall out at the quick lube place because they are > installed finger tight. > If you think the vibration is bad in an airplane check out the > vibration on an off road race truck. We lockwire on a lot of fasteners > but the drain bolt is just torqued. > Paul > ________________________________ Message 6 _____________________________________ Time: 12:48:36 PM PST US Subject: RotaxEngines-List: Re: Changing Crush Gasket From: "lucien" My .02, If I have a crush washer on me when I do my oil change, I replace it. I'll reuse old ones, tho. Copper will harden a bit once it's crushed so a used washer isn't as pliable as it was (besides already being flat as a pancake). But at the specified torque (195 in/lbs I believe?, can't remember off top of my head), the drain plug usually still gets a good seal and doesn't leak. And yes, I wouldn't even consider not safety-wiring the drain plug after installation new crush washer or no....... yeah it's extremely unlikely a properly torqued plug could come out but the wire reduces that probability to as close to zero as you can reasonably get for just a little bit of effort ;) LS -------- LS Titan II SS Read this topic online here: http://forums.matronics.com/viewtopic.php?p=195253#195253 ________________________________ Message 7 _____________________________________ Time: 02:36:05 PM PST US From: "Pete Christensen" Subject: RotaxEngines-List: Rotax oil pickup fitting at bottom of engine on 912 On my Kitfox III there is a fitting at the bottom of the 912ul engine where the oil return line attaches at 90 degrees and returns oil to the oil tank. I need to losen this fitting about 3 to 5 degrees so that the return hose is not kinked. There appears to be a copper washer between the fitting and the engine and I am sure if I loosen the fitting a few degrees that it will leak. How can I do this without causing a leak? Pete Hell Paso, TX ________________________________ Message 8 _____________________________________ Time: 09:51:46 PM PST US Subject: RotaxEngines-List: Re: Rotax oil pickup fitting at bottom of engine on 912 From: "Roger Lee" Hi Pete, You can loosen the bottom banjo nut just a little and rotate your hose without losing any oil and if you did lose a little it would be just a drop or two. I believe the torque on that banjo nut is 150 in/lbs. -------- 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=195312#195312 ------------------------------------------------------------------------------------- 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.