Newshound Posted June 1, 2012 Author Report Share Posted June 1, 2012 I don't currently have any means of carb heat on my 912ULS other than that radiated from the exhaust manifolds and I've never had any problem with icing. I'm going to install drip trays (Rotax or homemade TBD) under the carbs which will shield some of this heat. My question is will I now need to provide some other source of carb heat to avoid an icing situation?Thanks - MikeMore... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 1, 2012 Author Report Share Posted June 1, 2012 I don't currently have any means of carb heat on my 912ULS other than that radiated from the exhaust manifolds and I've never had any problem with icing. I'm going to install drip trays (Rotax or homemade TBD) under the carbs which will shield some of this heat. My question is will I now need to provide some other source of carb heat to avoid an icing situation?Thanks - MikeMore... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 2, 2012 Author Report Share Posted June 2, 2012 I wish to instal an oil thermastate. As I am disrupting the oil system I should be purging the system. Is there a procedure to do this other than pre heating the oil to above the thermastate opening temperature and using the standard procedure as listed in the service bulliten.More... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 2, 2012 Author Report Share Posted June 2, 2012 I wish to instal an oil thermastate. As I am disrupting the oil system I should be purging the system. Is there a procedure to do this other than pre heating the oil to above the thermastate opening temperature and using the standard procedure as listed in the service bulliten.More... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 2, 2012 Author Report Share Posted June 2, 2012 Hi all my 503 starts fine runs up to full power but at around 3000 rpms it lags or misses if it sits around those revs and you push the throttle forward it drops revs misses then picks up back to normal it also happens a 4300 rpms but not all the time. Not good when landing pull the power back to decend and need a bit of power to slow up the decent it takes a bit before any responce any suggestion what is happening .Cheers Geoff...More... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 2, 2012 Author Report Share Posted June 2, 2012 Hi all my 503 starts fine runs up to full power but at around 3000 rpms it lags or misses if it sits around those revs and you push the throttle forward it drops revs misses then picks up back to normal it also happens a 4300 rpms but not all the time. Not good when landing pull the power back to decend and need a bit of power to slow up the decent it takes a bit before any responce any suggestion what is happening .Cheers Geoff...More... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 2, 2012 Author Report Share Posted June 2, 2012 Greetings all,I've got a Rotax 912UL here, and the owner wants to do what's required to increase the TBO from 1500 to 2000 hours.Engine serial number is 4408210. Crankcase part number 888368. Crank Case Serial Number 06.2134According to SB-912-057UL, paragraph 3.4.1, "Replacement of a crankcase part no. 888364 (to S/N 27.811) through part no. 888368 or part no. 892654 (from S/N 06.0010) is required for TBO extension.Following Engines are affected:-912 UL From S/N 4,404718 to S/N 4.407859" This document is lousy with typos and bad grammar. This is a document describing the maintenance of an airplane engine; ambiguity here can cause errors in maintenance, errors in maintenance can kill pilots. As a repairman and pilot, I can tell you I don't want to kill or be killed because Rotax can't pony up the dough to have their $#&@ documents proofread by a native English speaker. The sentence describing whether or not I've got to REPLACE A CRANKCASE is completely incomprehensible. Maybe these documents SHOULD be issued by the FAA, then at least we'll get it from someone who can write in our own blankety-blanking language. The engine serial number isn't among those effected, but the crankcase part/serial numbers...might be? I can't make sense of it.More... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 2, 2012 Author Report Share Posted June 2, 2012 Greetings all,I've got a Rotax 912UL here, and the owner wants to do what's required to increase the TBO from 1500 to 2000 hours.Engine serial number is 4408210. Crankcase part number 888368. Crank Case Serial Number 06.2134According to SB-912-057UL, paragraph 3.4.1, "Replacement of a crankcase part no. 888364 (to S/N 27.811) through part no. 888368 or part no. 892654 (from S/N 06.0010) is required for TBO extension.Following Engines are affected:-912 UL From S/N 4,404718 to S/N 4.407859" This document is lousy with typos and bad grammar. This is a document describing the maintenance of an airplane engine; ambiguity here can cause errors in maintenance, errors in maintenance can kill pilots. As a repairman and pilot, I can tell you I don't want to kill or be killed because Rotax can't pony up the dough to have their $#&@ documents proofread by a native English speaker. The sentence describing whether or not I've got to REPLACE A CRANKCASE is completely incomprehensible. Maybe these documents SHOULD be issued by the FAA, then at least we'll get it from someone who can write in our own blankety-blanking language. The engine serial number isn't among those effected, but the crankcase part/serial numbers...might be? I can't make sense of it.More... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 4, 2012 Author Report Share Posted June 4, 2012 Hi,Is it ok to use the same straight 17mm hose between the expansion tank and cylinder number 3 as for the other cylinders or will the tighter bend radius restrict flow?Thanks,HarriMore... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 4, 2012 Author Report Share Posted June 4, 2012 Hi,Is it ok to use the same straight 17mm hose between the expansion tank and cylinder number 3 as for the other cylinders or will the tighter bend radius restrict flow?Thanks,HarriMore... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 4, 2012 Author Report Share Posted June 4, 2012 Many videos on oil change and oil service. Is there anything out there on fuel filter replacement and/or fuel service at intervals?More... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 4, 2012 Author Report Share Posted June 4, 2012 Many videos on oil change and oil service. Is there anything out there on fuel filter replacement and/or fuel service at intervals?More... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 4, 2012 Author Report Share Posted June 4, 2012 I have an oil injection system on my 582, the engine has now done 166 Hrs, what i would like to know is does the oil filter in the injection system need changing? i cannot find any reference to it in the service bookMore... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 4, 2012 Author Report Share Posted June 4, 2012 I have an oil injection system on my 582, the engine has now done 166 Hrs, what i would like to know is does the oil filter in the injection system need changing? i cannot find any reference to it in the service bookMore... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 5, 2012 Author Report Share Posted June 5, 2012 2009 912UL 100HP with 350 hours - aux generator/alternator not installedNot running and idling - voltage 12.5 voltsgreater than 3000 rpm - voltage 15.5 voltsUsually had about 14.5 volts for first 300 hoursChanged to a gel battery - would this cause the voltage to go up.Attached a Fluke voltmeter to the charging circuit - It reads the same as the panel voltmeterBattery, instruments and radios work great.Is there an adjustment to lower the regulator output?Should I leave well enough alone? TonyMore... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 5, 2012 Author Report Share Posted June 5, 2012 2009 912UL 100HP with 350 hours - aux generator/alternator not installedNot running and idling - voltage 12.5 voltsgreater than 3000 rpm - voltage 15.5 voltsUsually had about 14.5 volts for first 300 hoursChanged to a gel battery - would this cause the voltage to go up.Attached a Fluke voltmeter to the charging circuit - It reads the same as the panel voltmeterBattery, instruments and radios work great.Is there an adjustment to lower the regulator output?Should I leave well enough alone? TonyMore... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 5, 2012 Author Report Share Posted June 5, 2012 Please excuse the length of this posting but I want to get all the info in the initial post. Plane is RV12 with Rotax 912ULS, Dynon Flightdek (not Skyview) 120 hours TT. After two partial power losses on takeoff and complete testing of the fuel system,aux pump, and Dynon sender, the original fuel pump was replaced last summer with an off-the-shelf old model from Lockwood. All was well for maybe 30 hours with readings of 3.5-4.2 PSI (in the green) at all times. About 3 hours ago, I noticed the fuel pressure dropping into the mid-yellow range (2.2-2.5) on takeoff, recovering nicely shortly thereafter. It would do this irrespective of fuel on-board or ambient temperature.Because of my earlier problems, I always take off with the fuel pressure info front and center on the Dynon. I ordered and received from Lockwood a new-style pump. Installed it registered high 5's at low RPM's and high green at cruise. It dipped to low green on takeoff and fluctuated to low green with throttle reduction on return to field.My last three takeoffs have seen the fuel pressure drop to low 2's, again recovering at about pattern altitude. Again the pressure drops significantly at power reduction, then recovers below 4,000 RPM. Gauge reads 5.2 or better when I exit runway. There has been no takeoff loss of power felt or registered on the data download. Downloads confirm numbers seen on the panel. Fuel flow sometimes shows an increase in concert with pressure drops, sometimes not.My limited understanding of fluid dynamics tells me that a pressure drop would be expected on initial increase in flow (takeoff) and that reduction of power (approach to landing) would indicate increased pressure. Everybody I talk to says the range of fluctuation should not be this great.Can someone help me figure this out? The Dynon people have been very up-front about saying that their current sender is not as accurate as they would like it to be but a suitable replacement is not available. The RV12 POH calls for 2.2 PSI fuel pressure before takeoff (RPM not specified) but the aux pump puts out an indicated 2.3-2.6 at idle by itself. (Return line in RV12 plumbing reduces indicated output, I suppose, from Facet spec.For what it's worth, I chased the issue of vapor lock everywhere last summer and this is not the issue. Can't tell if I'm obsessing or snakebit... All suggestions appreciated.JimSouth TexasMore... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 5, 2012 Author Report Share Posted June 5, 2012 Hello flying friends,I've been looking in this forum for known problems about wear and degradation of the little smal plastic hat pushed in the wholes where the throttle spring clamps. I didn t find a lot execpt of one person having wear on a rans s6. I fly a flight design ct 2k of 2003 (and love it). i ve noticed in flight a bad carb sync only around 4300 rpm's and checked it before balancing. the problem is due to wear in the litlle hat what makes a difference in spring tension between two carbs in a 45° angle or something only and so carb balance is ok on lower rpm and higher rpm's. i tried to find this little hat on spare part sites but good luck, it's not easy to get. so I tried with something else and now it s temporarily ok. but still what I want to know from you:am I the only one having this? it seems pretty normal and reccurent and I find it strange nothing is said about it or spare parts are not availabledo you al have those little hats or does the majority fly without it with a metal metal contact? and if yes, is the spring stil strong enough?last but not least: do these dthrottle springs get bad after some years of normal use,? do we have to change them in a while? it seems to mee they re not strong enough... whilst some people rather have less tension springs.thanks guys for your informationcedric (belgium, EBUL)More... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 5, 2012 Author Report Share Posted June 5, 2012 Please excuse the length of this posting but I want to get all the info in the initial post. Plane is RV12 with Rotax 912ULS, Dynon Flightdek (not Skyview) 120 hours TT. After two partial power losses on takeoff and complete testing of the fuel system,aux pump, and Dynon sender, the original fuel pump was replaced last summer with an off-the-shelf old model from Lockwood. All was well for maybe 30 hours with readings of 3.5-4.2 PSI (in the green) at all times. About 3 hours ago, I noticed the fuel pressure dropping into the mid-yellow range (2.2-2.5) on takeoff, recovering nicely shortly thereafter. It would do this irrespective of fuel on-board or ambient temperature.Because of my earlier problems, I always take off with the fuel pressure info front and center on the Dynon. I ordered and received from Lockwood a new-style pump. Installed it registered high 5's at low RPM's and high green at cruise. It dipped to low green on takeoff and fluctuated to low green with throttle reduction on return to field.My last three takeoffs have seen the fuel pressure drop to low 2's, again recovering at about pattern altitude. Again the pressure drops significantly at power reduction, then recovers below 4,000 RPM. Gauge reads 5.2 or better when I exit runway. There has been no takeoff loss of power felt or registered on the data download. Downloads confirm numbers seen on the panel. Fuel flow sometimes shows an increase in concert with pressure drops, sometimes not.My limited understanding of fluid dynamics tells me that a pressure drop would be expected on initial increase in flow (takeoff) and that reduction of power (approach to landing) would indicate increased pressure. Everybody I talk to says the range of fluctuation should not be this great.Can someone help me figure this out? The Dynon people have been very up-front about saying that their current sender is not as accurate as they would like it to be but a suitable replacement is not available. The RV12 POH calls for 2.2 PSI fuel pressure before takeoff (RPM not specified) but the aux pump puts out an indicated 2.3-2.6 at idle by itself. (Return line in RV12 plumbing reduces indicated output, I suppose, from Facet spec.For what it's worth, I chased the issue of vapor lock everywhere last summer and this is not the issue. Can't tell if I'm obsessing or snakebit... All suggestions appreciated.JimSouth TexasMore... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 5, 2012 Author Report Share Posted June 5, 2012 Hello flying friends,I've been looking in this forum for known problems about wear and degradation of the little smal plastic hat pushed in the wholes where the throttle spring clamps. I didn t find a lot execpt of one person having wear on a rans s6. I fly a flight design ct 2k of 2003 (and love it). i ve noticed in flight a bad carb sync only around 4300 rpm's and checked it before balancing. the problem is due to wear in the litlle hat what makes a difference in spring tension between two carbs in a 45° angle or something only and so carb balance is ok on lower rpm and higher rpm's. i tried to find this little hat on spare part sites but good luck, it's not easy to get. so I tried with something else and now it s temporarily ok. but still what I want to know from you:am I the only one having this? it seems pretty normal and reccurent and I find it strange nothing is said about it or spare parts are not availabledo you al have those little hats or does the majority fly without it with a metal metal contact? and if yes, is the spring stil strong enough?last but not least: do these dthrottle springs get bad after some years of normal use,? do we have to change them in a while? it seems to mee they re not strong enough... whilst some people rather have less tension springs.thanks guys for your informationcedric (belgium, EBUL)More... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 5, 2012 Author Report Share Posted June 5, 2012 Greetings all,I just read an article in Kitplanes about the Whirlwind Propeller. In the article the author claims to gain 10mph in cruise and 10% in climb over the Warp Drive propeller when installed on a Rans S-7. I have been told several times that the Warp wasn't as efficient as some others because it was much heavier. Roger Lee has stated that all props are equal if pitched to run 5500 to 5600rpm WOT at your normal cruise altitude.I have managed to not spend the grand plus to find out if the Warp is less effeciant than others but I am now tempted. The article almost sounded like a paid advertizement. I am flying a Highlander with the Rotax 912uls and a 70" Warp. I just gained 5mph by ditching the bungee bags. It would be nice to gain 10mph by prop swapping.Any comments, positive or negative, will be appreciated.AlanMore... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 5, 2012 Author Report Share Posted June 5, 2012 Greetings all,I just read an article in Kitplanes about the Whirlwind Propeller. In the article the author claims to gain 10mph in cruise and 10% in climb over the Warp Drive propeller when installed on a Rans S-7. I have been told several times that the Warp wasn't as efficient as some others because it was much heavier. Roger Lee has stated that all props are equal if pitched to run 5500 to 5600rpm WOT at your normal cruise altitude.I have managed to not spend the grand plus to find out if the Warp is less effeciant than others but I am now tempted. The article almost sounded like a paid advertizement. I am flying a Highlander with the Rotax 912uls and a 70" Warp. I just gained 5mph by ditching the bungee bags. It would be nice to gain 10mph by prop swapping.Any comments, positive or negative, will be appreciated.AlanMore... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 6, 2012 Author Report Share Posted June 6, 2012 Hi there,I'm a newb here with a 912S fitted to my factory built 2 seat gyro. I have put 100hrs on it in the past 2 months and all has been well except a nagging issue. At full power there is a smell of fuel and there is a yellow/brown sticky residue left on the frame around the air filters. The mixture seems to be fine, the carbs are in sync, the engine develops good power and does not consume excessive fuel. The only other slight clue (maybe) is a dark discoloration of the prop right by the exhaust, but this takes some 10 hours or so to become noticeable.The smell is not too strong (but i am up wind from the pusher engine) and the residue only needs cleaning every few hours, but i am sure that this shows that the engine is not running as efficiently as it should/could. I also know that gyro's are considered high drag aircraft so i wonder if the engine is developing full power, and once that is reached, additional fuel is just being wasted.Sage forum members, I seek your thoughts and council.Thanks,NeilMore... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 6, 2012 Author Report Share Posted June 6, 2012 Hi there,I'm a newb here with a 912S fitted to my factory built 2 seat gyro. I have put 100hrs on it in the past 2 months and all has been well except a nagging issue. At full power there is a smell of fuel and there is a yellow/brown sticky residue left on the frame around the air filters. The mixture seems to be fine, the carbs are in sync, the engine develops good power and does not consume excessive fuel. The only other slight clue (maybe) is a dark discoloration of the prop right by the exhaust, but this takes some 10 hours or so to become noticeable.The smell is not too strong (but i am up wind from the pusher engine) and the residue only needs cleaning every few hours, but i am sure that this shows that the engine is not running as efficiently as it should/could. I also know that gyro's are considered high drag aircraft so i wonder if the engine is developing full power, and once that is reached, additional fuel is just being wasted.Sage forum members, I seek your thoughts and council.Thanks,NeilMore... Quote Link to comment Share on other sites More sharing options...
Newshound Posted June 7, 2012 Author Report Share Posted June 7, 2012 We completed a top over haul of out 912 ULS with new pistons, cleaned and lapped valves, engine runs great but we are leaking oil between the head and cylinder barrel at the through bolts. We found a service bulletin for gadgets/o-rings on the through bolt between the cylinder barrel and block. We install the o-rings but we still have the leak.We are stumped. More... Quote Link to comment Share on other sites More sharing options...
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