---------------------------------------------------------- RotaxEngines-List Digest Archive --- Total Messages Posted Thu 11/20/08: 12 ---------------------------------------------------------- Today's Message Index: ---------------------- 0. 12:32 AM - Behind By 21% - Advertising May Be Needed...? (Matt Dralle) 1. 01:22 AM - Re: 914 TCU seems dead (K Dilks) 2. 01:31 AM - Re: 912ul Sticking Valves and Carburetor questions. (K Dilks) 3. 04:34 AM - Re: 912ul Sticking Valves and Carburetor questions. (Catz631@aol.com) 4. 05:17 AM - Re: 912ul Sticking Valves and Carburetor questions. (Thom Riddle) 5. 07:07 AM - Re: Re: 914 TCU seems dead (Kevin Klinefelter) 6. 07:45 AM - Re: 912ul Sticking Valves and Carburetor questions. (pperrynas) 7. 07:56 AM - Re: 912ul Sticking Valves and Carburetor questions. (Thom Riddle) 8. 08:48 AM - Re: Re: 914 TCU seems dead (Dave Austin) 9. 02:45 PM - Re: 912ul Sticking Valves and Carburetor questions. (Roger Lee) 10. 08:22 PM - Re: 912ul Sticking Valves and Carburetor questions. (pperrynas) 11. 08:32 PM - Re: 912ul Sticking Valves and Carburetor questions. (Roger Lee) ________________________________ Message 0 _____________________________________ Time: 12:32:07 AM PST US From: Matt Dralle Subject: RotaxEngines-List: Behind By 21% - Advertising May Be Needed...? Dear Listers, The percentage of people making a Contribution to support the Lists this year is currently lagging behind last year by approximately 21%! I'm hoping that everyone is just waiting until the last minute to show their support... ;-) Please remember that it is solely your direct Contributions that keep these Lists up and running and most importantly - AD FREE! If the members don't want to support the Lists directly, then I will likely have to start adding advertisements to offset the costs of running the Lists. But I *really* don't want to have to start doing that. I really like the non-commercial atmosphere here and I think that a lot of the members appreciate that too. Please take a moment to make a Contribution today in support of the continued ad-free operation of all these Lists: http://www.matronics.com/contribution I want to send out a word of appreciation to all of the members that have already made their generous Contribution to support the Lists! Thank you! Matt Dralle Email List Administrator ________________________________ Message 1 _____________________________________ Time: 01:22:13 AM PST US Subject: RotaxEngines-List: Re: 914 TCU seems dead From: "K Dilks" I would say double check your voltage at the tcu connector, if the battery is low could be the snag. check also its not possible any water got in the large connector block and it has corrosion on the metal parts. Other than that very rare these fail. let us know what you find. -------- Austria ............. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=215288#215288 ________________________________ Message 2 _____________________________________ Time: 01:31:27 AM PST US Subject: RotaxEngines-List: Re: 912ul Sticking Valves and Carburetor questions. From: "K Dilks" Just to add to roger good advise , dont use oil additives just use a good bike oil. If the engine has sat a long time,sometimes the lead deposits start to come off the piston crown and cause some rough running but a good hard hours use with blow that out. Stick with unleaded. The carbs need some work as it sounds like the float valvse are a little leaky and /or the float height is out. Do a compression check to. -------- Austria ............. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=215289#215289 ________________________________ Message 3 _____________________________________ Time: 04:34:23 AM PST US From: Catz631@aol.com Subject: Re: RotaxEngines-List: 912ul Sticking Valves and Carburetor questions. Paul, I was going to suggest that you contact Roger as he is quite knowledgeable about the Rotax engine. I think he is spot on with his suggestions. The only things I might add are from the training I received at Lockwoods Rotax schoo l a while back (rapidly going bye..bye) Stick with auto fuel. 100 LL can cause lead deposits in the oil tank and valve sticking. Keep in mind the alcohol issue which has been brought up man y times. Rotax does not want you to use any additives,however,Marvel Mystery has been shown useful in the case of valve sticking or no compression on startup as mention by many members on this list. I don't think that would cause your problem. You might call a tech at Lockwood to get an opinion. I have found them ver y helpful with the problems I had with my engine. The instructor at Lockwoods school did mention in class that the most service problems on this engine oc cur from A & P mechanics. As Roger mentioned, unless they are trained on this engine they can sure @#&^% ! it up. Obviously owners can and do also. I high ly recommend the school! With that said your engine sounds like it is about the same vintage as mine. I have 190 hrs on it and it was delivered in 2001 I have a neat method of pneumatically syncing the carbs. You can have them synced in about a minute on the Kitfox 4 if you have the yoke throttle mechanism. Give me a call if you are interested. 850-304-7371 (cell) I wish I could add more. I had trouble with my engine running rough on throttle reduction. It ended up being in the throttle cables. One had more friction then the other and it was sticking. Then I had fuel spitting out of the carb intake when I replaced the float needles(due to time on the rubber tip) I went back to the old ones and problem solved. Then there was a broken module wire and dead mag and on and on. These engines take a bit of work.Call Lockwood o r Mississippi light aircraft.When you find the trouble please pass it to the group. Dick Maddu x Kitfox 4-1200 Pensacola, Fl **************Check out smokin=99 hot deals on laptops, desktops and m ore from Dell. Shop Deals ttp://ad.doubleclick.net/clk;209513277;31396581;l) ________________________________ Message 4 _____________________________________ Time: 05:17:12 AM PST US Subject: RotaxEngines-List: Re: 912ul Sticking Valves and Carburetor questions. From: "Thom Riddle" Paul, Roger and Dick's advice is all good. Where are you located? Maybe we can help you find a qualified Rotax mechanic in your area. http://riddletr.googlepages.com/a%26pmechanix -------- Thom Riddle CFI-SP Power Plant Mechanic N1208P RANS S6S, Tailwheel, 912UL N197BG FS1/447 -------------------- Scratch any cynic, he said, and youll find a disappointed idealist. George Carlin Read this topic online here: http://forums.matronics.com/viewtopic.php?p=215299#215299 ________________________________ Message 5 _____________________________________ Time: 07:07:46 AM PST US From: Kevin Klinefelter Subject: Re: RotaxEngines-List: Re: 914 TCU seems dead I checked the voltage at the big connector on the TCU, 12.5v.I keep the battery plugged in to a maintainer No corrosion or water as its hangered in the desert. Anything else I can check? Kevin K Dilks wrote: > > I would say double check your voltage at the tcu connector, if the battery is low could be the snag. check also its not possible any water got in the large connector block and it has corrosion on the metal parts. > Other than that very rare these fail. > let us know what you find. > > -------- > Austria ............. > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=215288#215288 > > > ________________________________ Message 6 _____________________________________ Time: 07:45:48 AM PST US Subject: RotaxEngines-List: Re: 912ul Sticking Valves and Carburetor questions. From: "pperrynas" First, thanks to all who replied and offered suggestions. This is why we feel the intake valves are sticking. We ran the engine for 1-2 min (very rough), then felt the exhaust on each cylinder and found cyl #2 was completly cold. We took off the rocker cover and by exerting force with palm of hand we could feel the slightest movement on the exhaust valve, but not on the intake valve. Even with a little leverage on the retainer washer with a flat screwdriver we could move the spring slightly but the valve stem did not (on the intake side, the exhaust side was ok). We then replaced the cover and ran engine again for 1-2 min and this time the #1 cyl exhaust was cold the #2 was hot. That's where we are right now, and my friend the A&P (30yrs exp) realizes his lack of knowledge on this engine so we are proceeding cautiously. The airplane was completed in 2001 and the owner/builder only put 70hrs on it as of this summer when I bought it. He had taken it to the rotax repair center in East Troy, WI in preparation for selling it and they are the facility that did the work incl carb socket replace/overhaul carbs, sync carbs,replaced valve spring retainers/keepers, and whatever R+R of intake manifolds is, as well as replaced the stator. As I said, once the engine warms up, it runs very smoothly, even at 1800 rpm and while I haven't had a compression check since the work done on it at 62hrs at the repair center (they all showed 87/87) it has plenty of power and compression seems good when turning the prop by hand after shutting engine down after having been run to normal temps. I have looked at diagrams of the bing carbs and they show the plastic tubes coming from the carb where I described in my first post, but I haven't been able to find a name/part # etc that might indicate their purpose? Are they some type of vent or overflow? It doesn't seem a good idea to have excess fuel coming out of them as it can fall on the exhaust. I'm located in southeast (rural) Missouri and am not aware of a Rotax service/repair fac! ility in this area, but I'll do some more checking and probably call Lockwood or the place that did the recent work on the engine..Again, thanks for everyone's advice, Paul P. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=215334#215334 ________________________________ Message 7 _____________________________________ Time: 07:56:02 AM PST US Subject: RotaxEngines-List: Re: 912ul Sticking Valves and Carburetor questions. From: "Thom Riddle" Paul, If the tubing you are talking about is what I think it is, they are venting tubes. No fuel should be coming out of them under normal circumstances, but are generally routed to a drip pan of some sort that has a drain tube routed outside of the engine compartment, for fire safety reasons. -------- Thom Riddle CFI-SP Power Plant Mechanic N1208P RANS S6S, Tailwheel, 912UL N197BG FS1/447 -------------------- Scratch any cynic, he said, and youll find a disappointed idealist. George Carlin Read this topic online here: http://forums.matronics.com/viewtopic.php?p=215338#215338 ________________________________ Message 8 _____________________________________ Time: 08:48:49 AM PST US From: "Dave Austin" Subject: Re: RotaxEngines-List: Re: 914 TCU seems dead Did you drain completely the fuel system, including the carb. float bowls, for that 6 month downtime? Gummy fuel can leave stuff in strange places left that long. Dave Austin 601HDS - 912 ________________________________ Message 9 _____________________________________ Time: 02:45:23 PM PST US Subject: RotaxEngines-List: Re: 912ul Sticking Valves and Carburetor questions. From: "Roger Lee" Hi Paul, Fuel doesn't come out of these tubes on normal operations unless the engine vibrates so bad it shakes the heck out of the carb floats or the float arms are not adjusted correctly. I would take the carbs off and check the float arm height. These tubes are vents and if the carbs overflow fuel will leak out. These tubes have to be in the right position. If they are out in the air stream or blocked off it will cause problems like rough running. If your differential pressure test and a static pressure test are all ok then a valve is not sticking. Mystery oil in the right concentrations won't hurt the engine, but don't mix all the other types fluids. Some people like to use the Mystery oil with 100LL, but we all recommend the 91 unleaded fuel. If you use 100LL alot then use a fuel additive like Decalin to help reduce the lead build up which will work better than Mystery oil. Mystery oil is like Chevy's and Ford's. You like it and use it or you don't like it. I personally don't see a real reason to use it with the Rotax engine. If it seems to be only when it's cold or low rpms then you may want to double check the enricher circuit (a.k.a. choke). -------- 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=215425#215425 ________________________________ Message 10 ____________________________________ Time: 08:22:52 PM PST US Subject: RotaxEngines-List: Re: 912ul Sticking Valves and Carburetor questions. From: "pperrynas" thanks again for the additional info...the reason I added the stabil to the auto fuel is Lockwood emphasized adding a stabilizer when using auto gas in their intro to rotax engines video. Is there a better stabilizer than the Stabil brand? Also, another question for Roger...is it possible that if the intake valve is sticking, could it cause "back pressure" to the carb causing fuel to back up through the vent tube?..just a thought.Again today, after running the engine (rough) for 3-4 minutes..moving throttle in and out some keeping rpm's between 2000 and 3000...it smoothed out and when temps came up to the normal range a mag check was normal...power felt normal in take off, climb, cruise..only had time for about 30 minutes of flight, but no problems and after shutting down engine the compression felt very firm on all blades turning by hand...Again, thanks to you all...I'll keep you informed as I work thru this, Paul P. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=215473#215473 ________________________________ Message 11 ____________________________________ Time: 08:32:47 PM PST US Subject: RotaxEngines-List: Re: 912ul Sticking Valves and Carburetor questions. From: "Roger Lee" Hi Paul, Using Stabil is fine, I just advise against mixing different types of fluids. I still think it is a carb problem. There are a couple of fuel stabilizers on the market. If you fly often enough there is no need for a fuel stabilizer. 91 octane shouldn't set in your plane or storage for more than approximately 4 weeks. 100LL is more stable for the long haul, but you pay the price in leading. If it was a valve it would be a problem all the time and not just start up or only for the first few minutes. It's hard sometimes to diagnose a problem through email or over the phone. -------- 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=215474#215474 ------------------------------------------------------------------------------------- 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.