---------------------------------------------------------- RotaxEngines-List Digest Archive --- Total Messages Posted Sun 03/31/13: 18 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:35 AM - Re: Rotax 912ULS Oil Check (Thom Riddle) 2. 06:54 AM - Re: Re: Rotax 912ULS Oil Check (FLYaDIVE) 3. 07:17 AM - Re: Rotax 912ULS Oil Check (Roger Lee) 4. 07:59 AM - Re: Rotax 912ULS Oil Check (krazydoc33) 5. 09:13 AM - Re: Re: Rotax 912ULS Oil Check (FLYaDIVE) 6. 10:11 AM - Re: Rotax 912ULS Oil Check (Roger Lee) 7. 02:17 PM - Re: Rotax 912ULS Oil Check (Alan Carter) 8. 02:25 PM - fuel return line? (rayj) 9. 02:37 PM - Re: fuel return line? (Peter Autenried) 10. 03:11 PM - Re: fuel return line? (Roger Lee) 11. 04:51 PM - Re: Re: fuel return line? (rayj) 12. 04:53 PM - Re: fuel return line? (Bob Comperini) 13. 05:04 PM - Re: Re: Rotax 912ULS Oil Check (jim.kulbeth@insightbb.com) 14. 05:05 PM - Re: Re: Rotax 912ULS Oil Check (jim.kulbeth@insightbb.com) 15. 05:17 PM - Re: Re: fuel return line? (Guy Buchanan) 16. 05:23 PM - Re: Re: Rotax 912ULS Oil Check (jim.kulbeth@insightbb.com) 17. 09:10 PM - Re: fuel return line? (Roger Lee) 18. 10:19 PM - Re: Re: fuel return line? (Guy Buchanan) ________________________________ Message 1 _____________________________________ Time: 05:35:14 AM PST US Subject: RotaxEngines-List: Re: Rotax 912ULS Oil Check From: "Thom Riddle" Jimmy, I am not Roger but am a powerplant mechanic with Rotax training and 10 years experience flying and maintaining Rotax 912 series engines. You do not want to overfill the oil tank. The only way to be sure you are not overfilling is to go through burp/gurgle process. If it reads anywhere near the middle or top of the acceptable range after sitting for several hours, it might be overfilled. The only way to know is to burp it and check. I've seen owners that did not understand this and filled the tank to the top mark when cold (after sitting for long time) and that way overfilled it. If you are certain there is sufficient oil in the tank, i.e., a good portion of the pickup tube is covered in oil, starting the engine and letting it idle will not hurt the engine. Shutting it down then checking the oil level will give you a better idea of actual oil quantity but it is not really a substitute for burping per operator's manual. -------- Thom Riddle Buffalo, NY (9G0) Kolb Slingshot SS-021 no engine FOR SALE Diamond Katana DA20-A1 Rotax 912 F3 Don't worry about old age... it doesn't last very long. - Anonymous Read this topic online here: http://forums.matronics.com/viewtopic.php?p=397400#397400 ________________________________ Message 2 _____________________________________ Time: 06:54:26 AM PST US Subject: Re: RotaxEngines-List: Re: Rotax 912ULS Oil Check From: FLYaDIVE Alan: I'm surprised you have to ask! If you want to be accepted by others you should gargle every morning after you brush your teeth. Your parent's should have taught you that! ;-) As for the engine - - It should not even be a question. Common sense would tell you that, you should have oil coating as much of the engine workings as possible BEFORE you start the engine. So - The determining factor is how much oil drips off the previously coated parts, during the time AFTER shutdown to BEFORE start up? SO - HOW MUCH? Ya don't know, do ya? You can't see inside the engine, can ya? So - What is the ONLY determining factor? Duh GURGLE, Duh! So - If ya gots duh Gurgle, ya gots duh oil. And it should be a part of every pre-flight inspection. But, you make the decision on how much time passes before you hit the start button. Maybe it is just a fuel stop - Or maybe just a food stop. Your decision. Now let me throw out another crazy question: I have noticed at local airport that experimental pilots fly more than other pilots. That is a very good thing. Maybe it has to do with the cost of gas or maybe they fly more for the love and fun of it. Either way that is a good thing. But, there will always be the neglected engine, one that sits for months without being started. So, what is the best procedure for starting an engine that has been sitting for months? Whoa! - Don't be so fast to answer... There is more to it. Consider this: The WORST part of starting a neglected engine is that the oil has drained off the Metal to Metal points that highly require the oil. If the oil has drained off, there is also the possibility of rust forming. Do you REALLY want to go through your NORMAL procedure before starting? This is one Drip that has been under that pressure and developed a procedure. Barry On Sat, Mar 30, 2013 at 6:09 PM, Alan Carter wrote: > alancarteresq@onetel.net> > > Can you have an" unknown" drip under pressure, ?? > Alan. > But the question is gurgle before or after ? > > ________________________________ Message 3 _____________________________________ Time: 07:17:26 AM PST US Subject: RotaxEngines-List: Re: Rotax 912ULS Oil Check From: "Roger Lee" Hi Jim, The reason the gurgle item was started a long time ago has to do with more than one item. First it can give you a more true reading. That said if it's already half way up the stick it can only go higher because it is just pushing some of the oil standing in the bottom of the crankcase back to the tank. The other and bigger reason was that the older oil filters were not as good as the one Rotax has now and because people would mount tanks too high or too low it would cause problems. Too high a mount like some Kitfox's and it might have caused the hydra-lock and too low a mount siphons oil out of the engine. One problem that rotating the prop checks for is hydra-lock. It's when the oil drained back to the cylinder because the oil tank was mounted too high and the old filters didn't stop that drain back. The new Rotax oil filters are very different now. They have a new more flexible anit drain back membrane, they now have an internal check valve that no other filter has and the by-pass pressure went from 13-16 psi to 18-22 psi which is much higher than our US oil filters set at 12-15 psi. So if you are using one of our auto filters from the US and you aren't doing yourself any favors. In the old days this wasn't true, but it is now. Checking the oil level by prop rotation is good, but just to let you know it can lie. Some Rotax owners check their oil every flight and some before and after the flight. I haven't heard of any hydra-lock cylinder issues for a long long time and it seemed to happen with the older engine's and older filters. So if you gave it a few turns then start the engine to check the oil it wouldn't hurt anything. It would help keep the system from lying to you. Here's the other thing. If you had a wet sump engine like a Continental, Lycoming, a car engine or a motorcycle you can over fill them with oil and possibly cause some issues depending on how over filled it is. The thing about a dry sump is you can't over fill the engine, the tank's separate. No matter what the level in the tank the engine always has the same amount of oil unless it is way too low of course. If you over fill our dry sump completely separate tank all it will do is over flow out the vent tube and make a big mess. (Been there done that) The engine will never know the difference because it doesn't care how much oil is in the SEPARATE tank. The oil pump only pumps so much oil at a given rate and it doesn't care about how much volume is in the tank. It pumps at that rate no matter what. -------- Roger Lee Tucson, Az. Light Sport Repairman - Maintenance Rated Rotax Repair Center - Heavy Maint. Rated Home 520-574-1080 TRY HOME FIRST Cell 520-349-7056 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=397411#397411 ________________________________ Message 4 _____________________________________ Time: 07:59:06 AM PST US Subject: RotaxEngines-List: Re: Rotax 912ULS Oil Check From: "krazydoc33" Roger's post regarding the oil tank being separate from the the engine is the most logical thing to consider. The engine does not know or care how much oil is in the tank unless it is really low. But being new to the Rotax why is it necessary to turn the the prop/engine over by hand at all before starting? Why not use the starter with the ignitions turned off? The amount of oil left on the internal parts is the same either way, using the starter turns the engine over a little faster. This procedure would not let one discover if there was a hydraulic lock problem but it sounds like that those are very rare now with the improved oil filter. Not at all like the problems with the older radials and rotarys. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=397414#397414 ________________________________ Message 5 _____________________________________ Time: 09:13:25 AM PST US Subject: Re: RotaxEngines-List: Re: Rotax 912ULS Oil Check From: FLYaDIVE Roger: A few corrections: HYDRO - not Hydra. Hydra is the seven headed mythical creature that Hercules slew. Lycoming and Continental engines DO NOT have a WET SUMP. They have a dry sump, cars do have a wet sump. A wet sump is one where the Crankshaft sits IN the oil, either partially or completely. This is not so for the Lycoming or Continental... Mater of fact, the Lycoming has a baffling between the crank and oil - not a totally sealed baffle but one that is about an 80% sealed. When you say: "they now have an internal check valve that no other filter has", what do you mean by that? Champion, Tempest and ADC, ALL have check valves. The reason for having check valves in an oil filter, especially these oil filters is: That the filter mounts high on the engine and without a check valve the oil would drain back into the engine sump and the engine would suffer oil reduction/starvation while starting and while building up pressure and flow. This is not a good thing. By-Pass - - What is Rotax's definition of By-Pass? On other engines it is the MINIMUM amount of oil pressure needed to OPEN the oil flow in the positive flow direction. So, why would you want to INCREASE the pressure required? It sounds like the check valve is set too high in pressure, so you also have a high by-pass pressure. It only has to work against gravity. OR Rotax's oil pump is not configured correctly to positively produce a pressure in only ONE direction. Why do you make the statement: "So if you are using one of our auto filters from the US and you aren't doing yourself any favors. In the old days this wasn't true, but it is now." Why isn't it true now? It sounds like there is a question in definitions? Back to Dry Sumps - Your statement becomes very misleading because of its inaccuracy. "If you had a wet sump engine like a Continental, Lycoming, a car engine or a motorcycle you can over fill them with oil and possibly cause some issues depending on how over filled it is." By the way a Dry Sump does not mean the oil tank is 'seperate", it only means the crank is not in the direct contact to the oil in the sump. Lycoming & Continental are DRY SUMPS. And you surly can OVER FILL a Lycoming & Continental. BUT! The difference is both these engines have a BREATHER TUBE, which is connected directly to the inside of the engine, there are NO check-valves or anti-siphoning systems. So any excess oil is simply BLOWN OUT the Breather Tube. The only damage that is done is, the Belly of your plane becomes very dirty and you have managed to Gouge out some more money from your wallet. Roger, you will have to comment on what damage is done to a Rotax engine if over filled. It would be interesting to see a FLOW DIAGRAM of how a Rotax handles oil and fuel. Extra Oil - If one want to add a separate oil storage tank it should be added on the return side of the oil flow. And this is dependent on where the oil feed back into the engine. On experimental planes that wish larger oil capacity this is done by: Adding a lower tank and connecting it to & from the sump <-- not the best, this has a flow problem. By adding a larger oil cooler <-- Very good as it also adds to the cooling, it is easier to heat an engine than to cool an engine. Larger and Multiple oil filters. <-- A bit of over kill. But the question is why one would need extra oil? Only thing I can think of is the FAA reg, but that refers to certified engines. Barry On Sun, Mar 31, 2013 at 10:17 AM, Roger Lee wrote: > > Hi Jim, > > The reason the gurgle item was started a long time ago has to do with more > than one item. First it can give you a more true reading. That said if it's > already half way up the stick it can only go higher because it is just > pushing some of the oil standing in the bottom of the crankcase back to the > tank. The other and bigger reason was that the older oil filters were not > as good as the one Rotax has now and because people would mount tanks too > high or too low it would cause problems. Too high a mount like some > Kitfox's and it might have caused the hydra-lock and too low a mount > siphons oil out of the engine. One problem that rotating the prop checks > for is hydra-lock. It's when the oil drained back to the cylinder because > the oil tank was mounted too high and the old filters didn't stop that > drain back. The new Rotax oil filters are very different now. They have a > new more flexible anit drain back membrane, they now have an internal check > valve that no other filter has and the! > by-pass pressure went from 13-16 psi to 18-22 psi which is much higher > than our US oil filters set at 12-15 psi. So if you are using one of our > auto filters from the US and you aren't doing yourself any favors. In the > old days this wasn't true, but it is now. > Checking the oil level by prop rotation is good, but just to let you know > it can lie. Some Rotax owners check their oil every flight and some before > and after the flight. I haven't heard of any hydra-lock cylinder issues for > a long long time and it seemed to happen with the older engine's and older > filters. So if you gave it a few turns then start the engine to check the > oil it wouldn't hurt anything. It would help keep the system from lying to > you. > > Here's the other thing. If you had a wet sump engine like a Continental, > Lycoming, a car engine or a motorcycle you can over fill them with oil and > possibly cause some issues depending on how over filled it is. The thing > about a dry sump is you can't over fill the engine, the tank's separate. No > matter what the level in the tank the engine always has the same amount of > oil unless it is way too low of course. If you over fill our dry sump > completely separate tank all it will do is over flow out the vent tube and > make a big mess. (Been there done that) The engine will never know the > difference because it doesn't care how much oil is in the SEPARATE tank. > The oil pump only pumps so much oil at a given rate and it doesn't care > about how much volume is in the tank. It pumps at that rate no matter what. > > -------- > Roger Lee > ________________________________ Message 6 _____________________________________ Time: 10:11:45 AM PST US Subject: RotaxEngines-List: Re: Rotax 912ULS Oil Check From: "Roger Lee" Hi Barry, Sorry for my typo spelling for hydra and hydro. For the sake of this debate and the Rotax, a wet sump is where the oil reserve is held within the engine and not a separate tank out side the engine. It isn't in the engine case. That's the most common conception for most people delineating between wet and dry sump in a Rotax conversation. It isn't worth splitting hairs because many won't know the difference as you are pointing out. Most all filters have an anti drain back membrane (actually some really poor ones don't) and is what you are calling a check valve (kind of like Hydra and Hydro), but it isn't a real check valve, just a membrane. Look in the Rotax filer next time and you'll see the check valve down in the middle and the anti drain back membrane around the edges of the holes, but no check valve in an automotive filter. Even the membrane was changed to be better and more flexible than most of the automotive filters. It was put there because of all the different ways owners were mounting their oil tanks. It's just an added protection feature. I guess you could say it protects the engine from owners. The bypass pressure was increased because they thought the by-pass mechanism, which isn't that accurate to start with (it's an emergency flow by pass only), was opening to often on start up allowing unfiltered oil to flow to the engine. The by-pass mechanism operates on a pressure differential between the up and down stream oil flow/pressure. My comments between Rotax, Continental's and Lycoming's is to try and get people away from maintenance comparisons. The Rotax is totally different in it's materials, design and workings. Oil and fuel flow diagrams are published and some are in the Rotax manuals. Once upon a time Rotax had equals in automotive filters you could buy across the counter, but that day has passed and I once thought that way, but after extensive research I now know different. -------- Roger Lee Tucson, Az. Light Sport Repairman - Maintenance Rated Rotax Repair Center - Heavy Maint. Rated Home 520-574-1080 TRY HOME FIRST Cell 520-349-7056 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=397426#397426 ________________________________ Message 7 _____________________________________ Time: 02:17:09 PM PST US Subject: RotaxEngines-List: Re: Rotax 912ULS Oil Check From: "Alan Carter" Hi Chaps. Roger that,s sounds a good explanation many thanks. I pull to prop over and it does not hurt me at 66. I have gurgled and filled to the top mark, and had oil all over the underside of the plane, I always top up now to keep it about a 1/4 " down the stick now and have not had the problem again. As for Starting and Stopping to check, I personally don,t like this idea as its another start, I like to keep my starts as low as possible, Another cycle logged in the book, a possible kick back, and on a 914 waiting for the temps to stabilizes, ete,ete, so to be easier on the plane and save my pocket i would rather but in a bit of muscle, just my choice. Alan Read this topic online here: http://forums.matronics.com/viewtopic.php?p=397454#397454 ________________________________ Message 8 _____________________________________ Time: 02:25:23 PM PST US From: rayj Subject: RotaxEngines-List: fuel return line? I'm plumbing the wings on my 750 and was wondering if the 912 uls needs a fuel return line to the tank. I'm guessing it doesn't, but I thought I'd better check. Thanks in advance. -- Raymond Julian Kettle River, MN. "And you know that I could have me a million more friends, and all I'd have to lose is my point of view." - John Prine ________________________________ Message 9 _____________________________________ Time: 02:37:08 PM PST US Subject: Re: RotaxEngines-List: fuel return line? From: Peter Autenried Not for the Rotax 912 ULS, but yes for the Rotax 912 iS. On Sun, Mar 31, 2013 at 4:24 PM, rayj wrote: > I'm plumbing the wings on my 750 and was wondering if the 912 uls needs > a fuel return line to the tank. I'm guessing it doesn't, but I thought > I'd better check. > > Thanks in advance. > > -- > Raymond Julian > Kettle River, MN. > > "And you know that I could have me a million more friends, > and all I'd have to lose is my point of view." - John Prine > > * > > * > > -- Peter Autenried 114 N Yale St. Vermillion, SD 57069 Home: (605) 658-0211 Work: (605) 677-5174 Cell: (860) 692-2781 ________________________________ Message 10 ____________________________________ Time: 03:11:26 PM PST US Subject: RotaxEngines-List: Re: fuel return line? From: "Roger Lee" Hi Raymond, The 912UL and ULS needs a return line. It is in the Installation manual. The orifice size is .035. The line comes off up by the carb feed where it bifurcates to the carbs on the cross over balance tube and can go back to either a wing, a header tank or the gascolator. It is absolutely necessary if you have the new style fuel pump or you may easily flood the carbs and puke fuel out the vent tube. This helps for carb flooding and vapor lock. I looked through the 912Si Installation manual and found no return line. Here are the pages from each Installation manual. -------- Roger Lee Tucson, Az. Light Sport Repairman - Maintenance Rated Rotax Repair Center - Heavy Maint. Rated Home 520-574-1080 TRY HOME FIRST Cell 520-349-7056 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=397460#397460 Attachments: http://forums.matronics.com//files/912_fuel_injection_installation_manual_150.pdf http://forums.matronics.com//files/912uls_rotax_installation_manual_326.pdf ________________________________ Message 11 ____________________________________ Time: 04:51:59 PM PST US From: rayj Subject: Re: RotaxEngines-List: Re: fuel return line? Thanks, that's what I needed. I haven't purchased the engine yet, so no installation manual. Raymond Julian Kettle River, MN. "And you know that I could have me a million more friends, and all I'd have to lose is my point of view." - John Prine On 03/31/2013 05:11 PM, Roger Lee wrote: > > Hi Raymond, > > The 912UL and ULS needs a return line. It is in the Installation manual. The orifice size is .035. The line comes off up by the carb feed where it bifurcates to the carbs on the cross over balance tube and can go back to either a wing, a header tank or the gascolator. It is absolutely necessary if you have the new style fuel pump or you may easily flood the carbs and puke fuel out the vent tube. This helps for carb flooding and vapor lock. > > I looked through the 912Si Installation manual and found no return line. Here are the pages from each Installation manual. > > -------- > Roger Lee > Tucson, Az. > Light Sport Repairman - Maintenance Rated > Rotax Repair Center - Heavy Maint. Rated > Home 520-574-1080 TRY HOME FIRST > Cell 520-349-7056 > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=397460#397460 > > > Attachments: > > http://forums.matronics.com//files/912_fuel_injection_installation_manual_150.pdf > http://forums.matronics.com//files/912uls_rotax_installation_manual_326.pdf > > ________________________________ Message 12 ____________________________________ Time: 04:53:10 PM PST US From: Bob Comperini Subject: Re: RotaxEngines-List: fuel return line? On 02:36 PM 3/31/2013, Peter Autenried wrote: >Not for the Rotax 912 ULS, but yes for the Rotax 912 iS. Huh? That's wrong. -- Bob Comperini e-mail: bob@fly-ul.com WWW: http://www.fly-ul.com ________________________________ Message 13 ____________________________________ Time: 05:04:04 PM PST US Subject: Re: RotaxEngines-List: Re: Rotax 912ULS Oil Check From: "jim.kulbeth@insightbb.com" Thanks, my engine is a late model. Made in 2008. I use the Rotax filter. Ha te to pay $19 bucks for a filter but guess it is worth it. I have not been b urping my engine because when I check it is always half full. However mine b urps quickly and being safe far outweighs sorry. Jimmy Kulbeth On Mar 31, 2013, at 11:12, FLYaDIVE wrote: > Roger: > > A few corrections: > HYDRO - not Hydra. Hydra is the seven headed mythical creature that Hercu les slew. > > Lycoming and Continental engines DO NOT have a WET SUMP. They have a dry s ump, cars do have a wet sump. A wet sump is one where the Crankshaft sits I N the oil, either partially or completely. This is not so for the Lycoming o r Continental... Mater of fact, the Lycoming has a baffling between the cran k and oil - not a totally sealed baffle but one that is about an 80% sealed. > > When you say: "they now have an internal check valve that no other filter h as", what do you mean by that? Champion, Tempest and ADC, ALL have check va lves. The reason for having check valves in an oil filter, especially these oil filters is: That the filter mounts high on the engine and without a che ck valve the oil would drain back into the engine sump and the engine would s uffer oil reduction/starvation while starting and while building up pressure and flow. This is not a good thing. > > By-Pass - - What is Rotax's definition of By-Pass? On other engines it is the MINIMUM amount of oil pressure needed to OPEN the oil flow in the posit ive flow direction. So, why would you want to INCREASE the pressure require d? It sounds like the check valve is set too high in pressure, so you also h ave a high by-pass pressure. It only has to work against gravity. OR Rotax 's oil pump is not configured correctly to positively produce a pressure in o nly ONE direction. > > Why do you make the statement: "So if you are using one of our auto filter s from the US and you aren't doing yourself any favors. In the old days this wasn't true, but it is now." Why isn't it true now? It sounds like there i s a question in definitions? > > Back to Dry Sumps - Your statement becomes very misleading because of its i naccuracy. "If you had a wet sump engine like a Continental, Lycoming, a ca r engine or a motorcycle you can over fill them with oil and possibly cause s ome issues depending on how over filled it is." By the way a Dry Sump does n ot mean the oil tank is 'seperate", it only means the crank is not in the di rect contact to the oil in the sump. Lycoming & Continental are DRY SUMPS. And you surly can OVER FILL a Lycoming & Continental. BUT! The difference is both these engines have a BREATHER TUBE, which is connected directly to t he inside of the engine, there are NO check-valves or anti-siphoning systems . So any excess oil is simply BLOWN OUT the Breather Tube. The only damage that is done is, the Belly of your plane becomes very dirty and you have ma naged to Gouge out some more money from your wallet. Roger, you will have t o comment on what damage is done to a Rotax engine if over filled. It would be interesting to see a FLOW DIAGRAM of how a Rotax handles oil and fuel. > > Extra Oil - If one want to add a separate oil storage tank it should be ad ded on the return side of the oil flow. And this is dependent on where the o il feed back into the engine. On experimental planes that wish larger oil c apacity this is done by: Adding a lower tank and connecting it to & from th e sump <-- not the best, this has a flow problem. By adding a larger oil co oler <-- Very good as it also adds to the cooling, it is easier to heat an e ngine than to cool an engine. Larger and Multiple oil filters. <-- A bit o f over kill. But the question is why one would need extra oil? Only thing I can think of is the FAA reg, but that refers to certified engines. > > Barry > > > > > > > > > On Sun, Mar 31, 2013 at 10:17 AM, Roger Lee wrote: > >> >> Hi Jim, >> >> The reason the gurgle item was started a long time ago has to do with mor e than one item. First it can give you a more true reading. That said if it' s already half way up the stick it can only go higher because it is just pus hing some of the oil standing in the bottom of the crankcase back to the tan k. The other and bigger reason was that the older oil filters were not as go od as the one Rotax has now and because people would mount tanks too high or too low it would cause problems. Too high a mount like some Kitfox's and it might have caused the hydra-lock and too low a mount siphons oil out of the engine. One problem that rotating the prop checks for is hydra-lock. It's w hen the oil drained back to the cylinder because the oil tank was mounted to o high and the old filters didn't stop that drain back. The new Rotax oil fi lters are very different now. They have a new more flexible anit drain back m embrane, they now have an internal check valve that no other filter has and t he! >> by-pass pressure went from 13-16 psi to 18-22 psi which is much higher t han our US oil filters set at 12-15 psi. So if you are using one of our auto filters from the US and you aren't doing yourself any favors. In the old da ys this wasn't true, but it is now. >> Checking the oil level by prop rotation is good, but just to let you know it can lie. Some Rotax owners check their oil every flight and some before a nd after the flight. I haven't heard of any hydra-lock cylinder issues for a long long time and it seemed to happen with the older engine's and older fi lters. So if you gave it a few turns then start the engine to check the oil i t wouldn't hurt anything. It would help keep the system from lying to you. >> >> Here's the other thing. If you had a wet sump engine like a Continental, L ycoming, a car engine or a motorcycle you can over fill them with oil and po ssibly cause some issues depending on how over filled it is. The thing about a dry sump is you can't over fill the engine, the tank's separate. No matte r what the level in the tank the engine always has the same amount of oil un less it is way too low of course. If you over fill our dry sump completely s eparate tank all it will do is over flow out the vent tube and make a big me ss. (Been there done that) The engine will never know the difference because it doesn't care how much oil is in the SEPARATE tank. The oil pump only pum ps so much oil at a given rate and it doesn't care about how much volume is i n the tank. It pumps at that rate no matter what. >> >> -------- >> Roger Lee > > > ========================== ========= ========================== ========= ========================== ========= ========================== ========= > ________________________________ Message 14 ____________________________________ Time: 05:05:32 PM PST US Subject: Re: RotaxEngines-List: Re: Rotax 912ULS Oil Check From: "jim.kulbeth@insightbb.com" Thanks. I plan to burp in the future. Jimmy Kulbeth On Mar 31, 2013, at 7:34, "Thom Riddle" wrote: > > Jimmy, > I am not Roger but am a powerplant mechanic with Rotax training and 10 years experience flying and maintaining Rotax 912 series engines. > > You do not want to overfill the oil tank. The only way to be sure you are not overfilling is to go through burp/gurgle process. If it reads anywhere near the middle or top of the acceptable range after sitting for several hours, it might be overfilled. The only way to know is to burp it and check. I've seen owners that did not understand this and filled the tank to the top mark when cold (after sitting for long time) and that way overfilled it. > > If you are certain there is sufficient oil in the tank, i.e., a good portion of the pickup tube is covered in oil, starting the engine and letting it idle will not hurt the engine. Shutting it down then checking the oil level will give you a better idea of actual oil quantity but it is not really a substitute for burping per operator's manual. > > -------- > Thom Riddle > Buffalo, NY (9G0) > > Kolb Slingshot SS-021 > no engine > FOR SALE > > Diamond Katana DA20-A1 > Rotax 912 F3 > > Don't worry about old age... it doesn't last very long. > - Anonymous > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=397400#397400 > > > > > > > > > > ________________________________ Message 15 ____________________________________ Time: 05:17:40 PM PST US From: Guy Buchanan Subject: Re: RotaxEngines-List: Re: fuel return line? So if I can route the return to the gascolator, how is that different than simply routing it back to the fuel line on the pump inlet side? I understand the difference if I route to the top of the tank. (Theoretically no back pressure there, but certainly significant head pressure for a high wing installation.) Guy Buchanan Ramona, CA Kitfox IV-1200 / 912-S / Warp 3cs / 500 hrs. and grounded Now a glider pilot, too. On 3/31/2013 3:11 PM, Roger Lee wrote: > The 912UL and ULS needs a return line. It is in the Installation manual. The orifice size is .035. The line comes off up by the carb feed where it bifurcates to the carbs on the cross over balance tube and can go back to either a wing, a header tank or the gascolator. It is absolutely necessary if you have the new style fuel pump or you may easily flood the carbs and puke fuel out the vent tube. This helps for carb flooding and vapor lock. > ________________________________ Message 16 ____________________________________ Time: 05:23:33 PM PST US Subject: Re: RotaxEngines-List: Re: Rotax 912ULS Oil Check From: "jim.kulbeth@insightbb.com" Well burp, gurgle, burgle I am in. However my planes do not sit long enough for the oil to drip off. A really good oil holds on for a while. I will not let an engine sit for a long period even in the winter. Jimmy Kulbeth On Mar 31, 2013, at 8:53, FLYaDIVE wrote: > Alan: > > I'm surprised you have to ask! If you want to be accepted by others you s hould gargle every morning after you brush your teeth. Your parent's should have taught you that! ;-) > > As for the engine - - It should not even be a question. Common sense woul d tell you that, you should have oil coating as much of the engine workings a s possible BEFORE you start the engine. So - The determining factor is how m uch oil drips off the previously coated parts, during the time AFTER shutdow n to BEFORE start up? SO - HOW MUCH? Ya don't know, do ya? You can't see inside the engine, can ya? So - What is the ONLY determining factor? Duh G URGLE, Duh! So - If ya gots duh Gurgle, ya gots duh oil. And it should be a part of every pre-flight inspection. But, you make the decision on how muc h time passes before you hit the start button. Maybe it is just a fuel stop - Or maybe just a food stop. Your decision. > > Now let me throw out another crazy question: > I have noticed at local airport that experimental pilots fly more than oth er pilots. That is a very good thing. Maybe it has to do with the cost of g as or maybe they fly more for the love and fun of it. Either way that is a g ood thing. But, there will always be the neglected engine, one that sits fo r months without being started. > So, what is the best procedure for starting an engine that has been sittin g for months? Whoa! - Don't be so fast to answer... There is more to it. C onsider this: The WORST part of starting a neglected engine is that the oil has drained off the Metal to Metal points that highly require the oil. If t he oil has drained off, there is also the possibility of rust forming. Do y ou REALLY want to go through your NORMAL procedure before starting? > > This is one Drip that has been under that pressure and developed a procedu re. > > Barry > > > On Sat, Mar 30, 2013 at 6:09 PM, Alan Carter wr ote: tel.net> >> >> Can you have an" unknown" drip under pressure, ?? >> Alan. >> But the question is gurgle before or after ? > > > ========================== ========= ========================== ========= ========================== ========= ========================== ========= > ________________________________ Message 17 ____________________________________ Time: 09:10:01 PM PST US Subject: RotaxEngines-List: Re: fuel return line? From: "Roger Lee" Hi Guy, All the Flight Design's have the return line back to the gascolator. I think it needs to go back far enough to make sure it gets cool fuel and not warm or hot fuel. They put the warm fuel from the top back down to cooler fuel. This is what help reduce the chance of vapor lock. If it went back into a line up on the engine then it would all be warm or hot fuel and serve no purpose as far as the vapor lock part. I haven't personally seen any go back into a line up on the engine. -------- Roger Lee Tucson, Az. Light Sport Repairman - Maintenance Rated Rotax Repair Center - Heavy Maint. Rated Home 520-574-1080 TRY HOME FIRST Cell 520-349-7056 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=397498#397498 ________________________________ Message 18 ____________________________________ Time: 10:19:17 PM PST US From: Guy Buchanan Subject: Re: RotaxEngines-List: Re: fuel return line? Thanks Roger. So if I plumbed back into the inlet line, say at the firewall, eventually the looping fuel would be really hot, though I suppose it depends on the percentage of looping fuel versus that coming from the tanks. Do you have any idea what the ratio might be? (I guess if the FD's do it to the firewall it must work, though.) Guy Buchanan Ramona, CA Kitfox IV-1200 / 912-S / Warp 3cs / 500 hrs. and grounded Now a glider pilot, too. On 3/31/2013 9:09 PM, Roger Lee wrote: > All the Flight Design's have the return line back to the gascolator. I think it needs to go back far enough to make sure it gets cool fuel and not warm or hot fuel. They put the warm fuel from the top back down to cooler fuel. This is what help reduce the chance of vapor lock. If it went back into a line up on the engine then it would all be warm or hot fuel and serve no purpose as far as the vapor lock part. I haven't personally seen any go back into a line up on the engine. > ------------------------------------------------------------------------------------- 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.