---------------------------------------------------------- L29-List Digest Archive --- Total Messages Posted Fri 03/25/16: 9 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:53 AM - Re: Nitrogen Loss (Jorgen Nielsen) 2. 10:19 AM - Re: Nitrogen Loss (Bill Culberson) 3. 12:07 PM - Re: Nitrogen Loss (Frank Deeth) 4. 12:51 PM - Re: Nitrogen Loss (Jorgen Nielsen) 5. 12:59 PM - Re: Nitrogen Loss (Frank Deeth) 6. 07:37 PM - Re: Nitrogen Loss (Jean de Roubin) 7. 07:53 PM - Re: Nitrogen Loss (migfighter42) 8. 11:26 PM - Re: Nitrogen Loss (Bill Geipel) 9. 11:27 PM - Re: Nitrogen Loss (Bill Geipel) ________________________________ Message 1 _____________________________________ Time: 12:53:31 AM PST US From: "Jorgen Nielsen" Subject: RE: L29-List: Nitrogen Loss I also tried an ultrasonic leak detector, got a very expensive version on trial for a week from a specialty supplier. Could not find anything using it either. Soapy water is messy but seems to work best. My air system is modified, with a hand valve installed close to the bottles. When I am done flying, I shut it off. Also nice if using the L29 to go somewhere, turn it off after landing, turn it back on before flight, no losses. From: owner-l29-list-server@matronics.com [mailto:owner-l29-list-server@matronics.com] On Behalf Of Anthony Royal Sent: Friday, 25 March 2016 02:17 Subject: Re: L29-List: Nitrogen Loss Hey guys, Thanks for all your suggestions! John, I did the soapy water test on every fitting I could find all the way back to the fittings for the emergency bottle and beyond. ...tightened too. No Joy. Bill, I think I did the top nut but missed the lower nut. I'll look at that next . Yeah, I'm 60 and a little too big to get into that small of quarters. Hey Frank, thanks for the info too! I'm also looking at disconnecting the the main pressurizing line line at the pressure reduction valve for the down stream items, after the nitrogen bottles, and capping off the line and then pressurizing the bottles. This should tell me if there is a leak anywhere upstream of the reduction valve in the main charging system. The emergency bottle holds pressure perfectly so no problems there. According to the service manual, the minimum loss is 5 atm over 2 hours. So, I'm right on that limit at 2.5 atm per hour. Thanks! Tony On Thursday, March 24, 2016 7:15 PM, John Cabrera wrote: I don=9Dt know if this is going to be of any help and some may laugh at me but i was chasing at leak in the rear canopy. Bought a fancy ultrasonic leak detector and could not find any leak. Finally decided to check with old fashion soapy water and a spray bottle. That worked. John On Mar 23, 2016, at 8:22 AM, Anthony Royal wrote: Guys, my L-29 has always held nitrogen for days without much loss of pressure. Other day I pressurized to 140 atm because of a long flight and day. Pressure bled off immediately from 140 to about 90 atm before I could get out of the hangar. And was totally empty the next day. I found several loose, original safety wired, connections not tight. Packing nut on the nitrogen purge valve was loose too. Tightened every fitting and thing I could find from nose to rear cockpit. Now, if I pressurize to 50 atm, I will lose 30 atm in 12 hours. If I pressurize to 100 atm I lose 30 atm in 12 hours. Very consistent now. That's about 2.5 atm per hour. Any suggestions what else might cause such a consistent leak? Thinking maybe the pressure relief valve leaking? Check valve? Reading manuals and reviewing diagrams but thought maybe someone else may have run into this same problem and save a lot of time Someone, in a post I can't find, suggested an ultrasonic tester of some sort to detect high pressure leaks. Does anyone know which one it was? Also, looking for the glass lens for the taxi light. Rock must have hit mineand cracked it in half. Glued it back but would like to replacement. Also looking for connector to ARC EA-401A encoding altimeter. Thanks for any info Anthony ________________________________ Message 2 _____________________________________ Time: 10:19:14 AM PST US From: Bill Culberson Subject: RE: L29-List: Nitrogen Loss VWx0cmFzb25pYyBsZWFrIGRldGVjdG9yIG9ubHkgd29ya3Mgb24gdGhlIGhpZ2ggcHJlc3N1cmUg bGVha3MgKDc1LTEwMCBCQVIpLCBhcyBpdCBkZXRlY3RzIHRoZSBzcGVjaWZpYyBhdWRpbyBzaWdu YXR1cmUgb2YgaGlnaCBwcmVzc3VyZSBnYXMgZXNjYXBpbmcuIENhbm9weSBzZWFscyBhbmQgYnJh a2VzIGFyZSBhdCBsb3dlciBwcmVzc3VyZXMgYW5kIHRoZSBzb2FwIGFuZCB3YXRlciB0ZXN0IHNl ZW1zIGJlc3QuDQoNCkkgZG9u4oCZdCB1c2UgYSBTY2hyYWRlciB2YWx2ZSBidXQgcmF0aGVyIHRo ZSBvcmlnaW5hbCBxdWFydGVyIHR1cm4gdmFsdmUgYnV0IHJlY2VudGx5IGNvbnZlcnRlZCB0aGUg TjIgQ292ZXIgdG8gaGF2aW5nIGEgU2NocmFkZXIgYWRhcHRlciDigJxqdXN0IGluIGNhc2XigJ0u IE15IHBsYW5lIGRvZXNu4oCZdCBsZWFrIG11Y2ggYnV0IGRpc2NvdmVyZWQgdGhhdCB3aXRoIHRo ZSBjb3ZlciBjaGFuZ2VkIGFuZCBhIGdvb2QgZ2Fza2V0IHRoZSBOMiBjb3ZlciB0aGF0IHRoZSBO MiByZW1haW5zIGZvciB3ZWVrcyBpbnN0ZWFkIG9mIGRheXMuIE1haW4gY2hlY2sgdmFsdmUgbXVz 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dC4gIEFsc28gbG9va2luZyBmb3IgY29ubmVjdG9yIHRvIEFSQyBFQS00MDFBIGVuY29kaW5nIGFs dGltZXRlci4NCg0KVGhhbmtzIGZvciBhbnkgaW5mbw0KDQpBbnRob255DQoNCg0K ________________________________ Message 3 _____________________________________ Time: 12:07:29 PM PST US From: Frank Deeth Subject: Re: L29-List: Nitrogen Loss I read once about an L-29 being operated in the UK where they disconnected t he oxy system and plumbed those bottles into the pneumatic system, almost do ubles the capacity if I recall...? Has anyone else looked at doing that? Frank Sent from my iPad > On Mar 26, 2016, at 4:20 AM, Bill Culberson w rote: > > Ultrasonic leak detector only works on the high pressure leaks (75-100 BAR ), as it detects the specific audio signature of high pressure gas escaping. Canopy seals and brakes are at lower pressures and the soap and water test s eems best. > > I don=99t use a Schrader valve but rather the original quarter turn v alve but recently converted the N2 Cover to having a Schrader adapter =9Cjust in case=9D. My plane doesn=99t leak much but discovered t hat with the cover changed and a good gasket the N2 cover that the N2 remain s for weeks instead of days. Main check valve must be leaking. > > I like the Hand valve at the tanks, what did you use? Pics? > > Bill > N39DE > > From: owner-l29-list-server@matronics.com [mailto:owner-l29-list-server@ma tronics.com] On Behalf Of Jorgen Nielsen > Sent: Friday, March 25, 2016 2:52 AM > To: l29-list@matronics.com > Subject: RE: L29-List: Nitrogen Loss > > I also tried an ultrasonic leak detector, got a very expensive version on t rial for a week from a specialty supplier. Could not find anything using it either. Soapy water is messy but seems to work best. > > My air system is modified, with a hand valve installed close to the bottle s. When I am done flying, I shut it off. Also nice if using the L29 to go s omewhere, turn it off after landing, turn it back on before flight, no losse s. > > From: owner-l29-list-server@matronics.com [mailto:owner-l29-list-server@ma tronics.com] On Behalf Of Anthony Royal > Sent: Friday, 25 March 2016 02:17 > To: l29-list@matronics.com > Subject: Re: L29-List: Nitrogen Loss > > Hey guys, > Thanks for all your suggestions! John, I did the soapy water test on ever y fitting I could find all the way back to the fittings for the emergency bo ttle and beyond. ...tightened too. No Joy. > > Bill, I think I did the top nut but missed the lower nut. I'll look at tha t next . Yeah, I'm 60 and a little too big to get into that small of quarter s. > > Hey Frank, thanks for the info too! > > I'm also looking at disconnecting the the main pressurizing line line at t he pressure reduction valve for the down stream items, after the nitrogen bo ttles, and capping off the line and then pressurizing the bottles. This shou ld tell me if there is a leak anywhere upstream of the reduction valve in th e main charging system. The emergency bottle holds pressure perfectly so no p roblems there. > > According to the service manual, the minimum loss is 5 atm over 2 hours. S o, I'm right on that limit at 2.5 atm per hour. > > Thanks! > Tony > > > > > > On Thursday, March 24, 2016 7:15 PM, John Cabrera wrote : > > > I don=9Dt know if this is going to be of any help and some may laugh at me but i was chasing at leak in the rear canopy. Bought a fancy ultraso nic leak detector and could not find any leak. Finally decided to check wit h old fashion soapy water and a spray bottle. That worked. > > John > > > > On Mar 23, 2016, at 8:22 AM, Anthony Royal wrote: > > Guys, my L-29 has always held nitrogen for days without much loss of pres sure. Other day I pressurized to 140 atm because of a long flight and day. P ressure bled off immediately from 140 to about 90 atm before I could get out of the hangar. And was totally empty the next day. I found several loose, o riginal safety wired, connections not tight. Packing nut on the nitrogen pur ge valve was loose too. Tightened every fitting and thing I could find from n ose to rear cockpit. > > Now, if I pressurize to 50 atm, I will lose 30 atm in 12 hours. If I press urize to 100 atm I lose 30 atm in 12 hours. Very consistent now. That's abo ut 2.5 atm per hour. Any suggestions what else might cause such a consisten t leak? Thinking maybe the pressure relief valve leaking? Check valve? Read ing manuals and reviewing diagrams but thought maybe someone else may have r un into this same problem and save a lot of time > > Someone, in a post I can't find, suggested an ultrasonic tester of some so rt to detect high pressure leaks. Does anyone know which one it was? > > Also, looking for the glass lens for the taxi light. Rock must have hit mi neand cracked it in half. Glued it back but would like to replacement. Also looking for connector to ARC EA-401A encoding altimeter. > > Thanks for any info > > Anthony > > ________________________________ Message 4 _____________________________________ Time: 12:51:36 PM PST US From: "Jorgen Nielsen" Subject: RE: L29-List: Nitrogen Loss Mine is also done like that. I only posted half the story earlier, herewith then the full story J I don=99t use oxygen, so repurposed the tanks. My oxygen tanks have a tap on them, close to the bottles, and a pressure gauge. The tap & gauge is situated in the nose compartment. My normal air bottle (N2) also have a tap on them, and a gauge, also in the nose compartment. So far, 2 separate systems. After the taps, they are interconnected via a T, output goes to the air system. Benefits: Closing the valves means no leaks when she is standing. Having the 2 systems that close means I can go away for a weekend with no ground support, or for example a 3 hop ferry I did a while back. At the destination, close the active system. For the next flight, pick a system and open valve. When the system is empty use the next one. To fill, if its just a normal flight from home base, I open the valve for whichever system is in use, and fill normally. For extended flights, one can fill one system at a time, or open both and fill both, then close one. So far, completely trouble free for a number of years. I will have to take some pics when at the airport. I used spare hand operated valves, similar to the pressure release inside the cockpit. I never did the work myself, I have a Russian guy who does all my maintenance, I just dreamt it up and asked him to do it. Another mod we did: my front / rear braking system has been reversed. I was once taxying with pax, and asked them to hold the brake while I did something. On release, when I took over, suddenly I had no brakes, and no steering obviously. We almost went farming. In normal ops, the rear brake is for the instructor, and held a certain way can disable the front cabin system. Not good for how we operate them privately. Regards to all Jorgen From: owner-l29-list-server@matronics.com [mailto:owner-l29-list-server@matronics.com] On Behalf Of Frank Deeth Sent: Friday, 25 March 2016 21:07 Subject: Re: L29-List: Nitrogen Loss I read once about an L-29 being operated in the UK where they disconnected the oxy system and plumbed those bottles into the pneumatic system, almost doubles the capacity if I recall...? Has anyone else looked at doing that? Frank Sent from my iPad On Mar 26, 2016, at 4:20 AM, Bill Culberson wrote: Ultrasonic leak detector only works on the high pressure leaks (75-100 BAR), as it detects the specific audio signature of high pressure gas escaping. Canopy seals and brakes are at lower pressures and the soap and water test seems best. I don=99t use a Schrader valve but rather the original quarter turn valve but recently converted the N2 Cover to having a Schrader adapter =9Cjust in case=9D. My plane doesn=99t leak much but discovered that with the cover changed and a good gasket the N2 cover that the N2 remains for weeks instead of days. Main check valve must be leaking. I like the Hand valve at the tanks, what did you use? Pics? Bill N39DE From: owner-l29-list-server@matronics.com [mailto:owner-l29-list-server@matronics.com] On Behalf Of Jorgen Nielsen Sent: Friday, March 25, 2016 2:52 AM Subject: RE: L29-List: Nitrogen Loss I also tried an ultrasonic leak detector, got a very expensive version on trial for a week from a specialty supplier. Could not find anything using it either. Soapy water is messy but seems to work best. My air system is modified, with a hand valve installed close to the bottles. When I am done flying, I shut it off. Also nice if using the L29 to go somewhere, turn it off after landing, turn it back on before flight, no losses. From: owner-l29-list-server@matronics.com [mailto:owner-l29-list-server@matronics.com] On Behalf Of Anthony Royal Sent: Friday, 25 March 2016 02:17 Subject: Re: L29-List: Nitrogen Loss Hey guys, Thanks for all your suggestions! John, I did the soapy water test on every fitting I could find all the way back to the fittings for the emergency bottle and beyond. ...tightened too. No Joy. Bill, I think I did the top nut but missed the lower nut. I'll look at that next . Yeah, I'm 60 and a little too big to get into that small of quarters. Hey Frank, thanks for the info too! I'm also looking at disconnecting the the main pressurizing line line at the pressure reduction valve for the down stream items, after the nitrogen bottles, and capping off the line and then pressurizing the bottles. This should tell me if there is a leak anywhere upstream of the reduction valve in the main charging system. The emergency bottle holds pressure perfectly so no problems there. According to the service manual, the minimum loss is 5 atm over 2 hours. So, I'm right on that limit at 2.5 atm per hour. Thanks! Tony On Thursday, March 24, 2016 7:15 PM, John Cabrera wrote: I don=9Dt know if this is going to be of any help and some may laugh at me but i was chasing at leak in the rear canopy. Bought a fancy ultrasonic leak detector and could not find any leak. Finally decided to check with old fashion soapy water and a spray bottle. That worked. John On Mar 23, 2016, at 8:22 AM, Anthony Royal wrote: Guys, my L-29 has always held nitrogen for days without much loss of pressure. Other day I pressurized to 140 atm because of a long flight and day. Pressure bled off immediately from 140 to about 90 atm before I could get out of the hangar. And was totally empty the next day. I found several loose, original safety wired, connections not tight. Packing nut on the nitrogen purge valve was loose too. Tightened every fitting and thing I could find from nose to rear cockpit. Now, if I pressurize to 50 atm, I will lose 30 atm in 12 hours. If I pressurize to 100 atm I lose 30 atm in 12 hours. Very consistent now. That's about 2.5 atm per hour. Any suggestions what else might cause such a consistent leak? Thinking maybe the pressure relief valve leaking? Check valve? Reading manuals and reviewing diagrams but thought maybe someone else may have run into this same problem and save a lot of time Someone, in a post I can't find, suggested an ultrasonic tester of some sort to detect high pressure leaks. Does anyone know which one it was? Also, looking for the glass lens for the taxi light. Rock must have hit mineand cracked it in half. Glued it back but would like to replacement. Also looking for connector to ARC EA-401A encoding altimeter. Thanks for any info Anthony ________________________________ Message 5 _____________________________________ Time: 12:59:26 PM PST US Subject: Re: L29-List: Nitrogen Loss From: Frank Deeth Thanks Jorgen! Sent from my iPhone > On 26 Mar 2016, at 6:50 AM, Jorgen Nielsen wro te: > > Mine is also done like that. I only posted half the story earlier, herewi th then the full story J > > I don=99t use oxygen, so repurposed the tanks. > > My oxygen tanks have a tap on them, close to the bottles, and a pressure g auge. The tap & gauge is situated in the nose compartment. > My normal air bottle (N2) also have a tap on them, and a gauge, also in th e nose compartment. > So far, 2 separate systems. > After the taps, they are interconnected via a T, output goes to the air sy stem. > > Benefits: > Closing the valves means no leaks when she is standing. > Having the 2 systems that close means I can go away for a weekend with no g round support, or for example a 3 hop ferry I did a while back. At the dest ination, close the active system. For the next flight, pick a system and op en valve. When the system is empty use the next one. > > To fill, if its just a normal flight from home base, I open the valve for w hichever system is in use, and fill normally. For extended flights, one can fill one system at a time, or open both and fill both, then close one. > > So far, completely trouble free for a number of years. > > I will have to take some pics when at the airport. I used spare hand oper ated valves, similar to the pressure release inside the cockpit. I never di d the work myself, I have a Russian guy who does all my maintenance, I just d reamt it up and asked him to do it. > > Another mod we did: my front / rear braking system has been reversed. I w as once taxying with pax, and asked them to hold the brake while I did somet hing. On release, when I took over, suddenly I had no brakes, and no steeri ng obviously. We almost went farming. In normal ops, the rear brake is for the instructor, and held a certain way can disable the front cabin system. Not good for how we operate them privately. > > Regards to all > Jorgen > > From: owner-l29-list-server@matronics.com [mailto:owner-l29-list-server@ma tronics.com] On Behalf Of Frank Deeth > Sent: Friday, 25 March 2016 21:07 > To: l29-list@matronics.com > Subject: Re: L29-List: Nitrogen Loss > > I read once about an L-29 being operated in the UK where they disconnected the oxy system and plumbed those bottles into the pneumatic system, almost d oubles the capacity if I recall...? Has anyone else looked at doing that? > > Frank > > Sent from my iPad > > On Mar 26, 2016, at 4:20 AM, Bill Culberson w rote: > > Ultrasonic leak detector only works on the high pressure leaks (75-100 BAR ), as it detects the specific audio signature of high pressure gas escaping. Canopy seals and brakes are at lower pressures and the soap and water test s eems best. > > I don=99t use a Schrader valve but rather the original quarter turn v alve but recently converted the N2 Cover to having a Schrader adapter =9Cjust in case=9D. My plane doesn=99t leak much but discovered t hat with the cover changed and a good gasket the N2 cover that the N2 remain s for weeks instead of days. Main check valve must be leaking. > > I like the Hand valve at the tanks, what did you use? Pics? > > Bill > N39DE > > From: owner-l29-list-server@matronics.com [mailto:owner-l29-list-server@ma tronics.com] On Behalf Of Jorgen Nielsen > Sent: Friday, March 25, 2016 2:52 AM > To: l29-list@matronics.com > Subject: RE: L29-List: Nitrogen Loss > > I also tried an ultrasonic leak detector, got a very expensive version on t rial for a week from a specialty supplier. Could not find anything using it either. Soapy water is messy but seems to work best. > > My air system is modified, with a hand valve installed close to the bottle s. When I am done flying, I shut it off. Also nice if using the L29 to go s omewhere, turn it off after landing, turn it back on before flight, no losse s. > > From: owner-l29-list-server@matronics.com [mailto:owner-l29-list-server@ma tronics.com] On Behalf Of Anthony Royal > Sent: Friday, 25 March 2016 02:17 > To: l29-list@matronics.com > Subject: Re: L29-List: Nitrogen Loss > > Hey guys, > Thanks for all your suggestions! John, I did the soapy water test on ever y fitting I could find all the way back to the fittings for the emergency bo ttle and beyond. ...tightened too. No Joy. > > Bill, I think I did the top nut but missed the lower nut. I'll look at tha t next . Yeah, I'm 60 and a little too big to get into that small of quarter s. > > Hey Frank, thanks for the info too! > > I'm also looking at disconnecting the the main pressurizing line line at t he pressure reduction valve for the down stream items, after the nitrogen bo ttles, and capping off the line and then pressurizing the bottles. This shou ld tell me if there is a leak anywhere upstream of the reduction valve in th e main charging system. The emergency bottle holds pressure perfectly so no p roblems there. > > According to the service manual, the minimum loss is 5 atm over 2 hours. S o, I'm right on that limit at 2.5 atm per hour. > > Thanks! > Tony > > > > > > On Thursday, March 24, 2016 7:15 PM, John Cabrera wrote : > > > I don=9Dt know if this is going to be of any help and some may laugh at me but i was chasing at leak in the rear canopy. Bought a fancy ultraso nic leak detector and could not find any leak. Finally decided to check wit h old fashion soapy water and a spray bottle. That worked. > > John > > > > On Mar 23, 2016, at 8:22 AM, Anthony Royal wrote: > > Guys, my L-29 has always held nitrogen for days without much loss of pres sure. Other day I pressurized to 140 atm because of a long flight and day. P ressure bled off immediately from 140 to about 90 atm before I could get out of the hangar. And was totally empty the next day. I found several loose, o riginal safety wired, connections not tight. Packing nut on the nitrogen pur ge valve was loose too. Tightened every fitting and thing I could find from n ose to rear cockpit. > > Now, if I pressurize to 50 atm, I will lose 30 atm in 12 hours. If I press urize to 100 atm I lose 30 atm in 12 hours. Very consistent now. That's abo ut 2.5 atm per hour. Any suggestions what else might cause such a consisten t leak? Thinking maybe the pressure relief valve leaking? Check valve? Read ing manuals and reviewing diagrams but thought maybe someone else may have r un into this same problem and save a lot of time > > Someone, in a post I can't find, suggested an ultrasonic tester of some so rt to detect high pressure leaks. Does anyone know which one it was? > > Also, looking for the glass lens for the taxi light. Rock must have hit mi neand cracked it in half. Glued it back but would like to replacement. Also looking for connector to ARC EA-401A encoding altimeter. > > Thanks for any info > > Anthony > > ________________________________ Message 6 _____________________________________ Time: 07:37:38 PM PST US From: Jean de Roubin Subject: Re: L29-List: Nitrogen Loss I think the best way is an air compressor, working automatically at 20 bars a nd stopping at 50. My, installed by the tzechs and approved by the factory is perfectly working since 15 years. No need of ground support. Jean de Roubin Envoy=C3=A9 de mon iPhone > Le 25 mars 2016 =C3- 19:58, Frank Deeth a =C3=A9cr it : > > Thanks Jorgen! > > Sent from my iPhone > >> On 26 Mar 2016, at 6:50 AM, Jorgen Nielsen wr ote: >> >> Mine is also done like that. I only posted half the story earlier, herew ith then the full story J >> >> I don=99t use oxygen, so repurposed the tanks. >> >> My oxygen tanks have a tap on them, close to the bottles, and a pressure g auge. The tap & gauge is situated in the nose compartment. >> My normal air bottle (N2) also have a tap on them, and a gauge, also in t he nose compartment. >> So far, 2 separate systems. >> After the taps, they are interconnected via a T, output goes to the air s ystem. >> >> Benefits: >> Closing the valves means no leaks when she is standing. >> Having the 2 systems that close means I can go away for a weekend with no ground support, or for example a 3 hop ferry I did a while back. At the de stination, close the active system. For the next flight, pick a system and o pen valve. When the system is empty use the next one. >> >> To fill, if its just a normal flight from home base, I open the valve for whichever system is in use, and fill normally. For extended flights, one c an fill one system at a time, or open both and fill both, then close one. >> >> So far, completely trouble free for a number of years. >> >> I will have to take some pics when at the airport. I used spare hand ope rated valves, similar to the pressure release inside the cockpit. I never d id the work myself, I have a Russian guy who does all my maintenance, I just dreamt it up and asked him to do it. >> >> Another mod we did: my front / rear braking system has been reversed. I was once taxying with pax, and asked them to hold the brake while I did som ething. On release, when I took over, suddenly I had no brakes, and no stee ring obviously. We almost went farming. In normal ops, the rear brake is f or the instructor, and held a certain way can disable the front cabin system . Not good for how we operate them privately. >> >> Regards to all >> Jorgen >> >> From: owner-l29-list-server@matronics.com [mailto:owner-l29-list-server@m atronics.com] On Behalf Of Frank Deeth >> Sent: Friday, 25 March 2016 21:07 >> To: l29-list@matronics.com >> Subject: Re: L29-List: Nitrogen Loss >> >> I read once about an L-29 being operated in the UK where they disconnecte d the oxy system and plumbed those bottles into the pneumatic system, almost doubles the capacity if I recall...? Has anyone else looked at doing that? >> >> Frank >> >> Sent from my iPad >> >> On Mar 26, 2016, at 4:20 AM, Bill Culberson wrote: >> >> Ultrasonic leak detector only works on the high pressure leaks (75-100 BA R), as it detects the specific audio signature of high pressure gas escaping . Canopy seals and brakes are at lower pressures and the soap and water test seems best. >> >> I don=99t use a Schrader valve but rather the original quarter turn valve but recently converted the N2 Cover to having a Schrader adapter =9Cjust in case=9D. My plane doesn=99t leak much but discovered t hat with the cover changed and a good gasket the N2 cover that the N2 remain s for weeks instead of days. Main check valve must be leaking. >> >> I like the Hand valve at the tanks, what did you use? Pics? >> >> Bill >> N39DE >> >> From: owner-l29-list-server@matronics.com [mailto:owner-l29-list-server@m atronics.com] On Behalf Of Jorgen Nielsen >> Sent: Friday, March 25, 2016 2:52 AM >> To: l29-list@matronics.com >> Subject: RE: L29-List: Nitrogen Loss >> >> I also tried an ultrasonic leak detector, got a very expensive version on trial for a week from a specialty supplier. Could not find anything using i t either. Soapy water is messy but seems to work best. >> >> My air system is modified, with a hand valve installed close to the bottl es. When I am done flying, I shut it off. Also nice if using the L29 to go somewhere, turn it off after landing, turn it back on before flight, no los ses. >> >> From: owner-l29-list-server@matronics.com [mailto:owner-l29-list-server@m atronics.com] On Behalf Of Anthony Royal >> Sent: Friday, 25 March 2016 02:17 >> To: l29-list@matronics.com >> Subject: Re: L29-List: Nitrogen Loss >> >> Hey guys, >> Thanks for all your suggestions! John, I did the soapy water test on eve ry fitting I could find all the way back to the fittings for the emergency b ottle and beyond. ...tightened too. No Joy. >> >> Bill, I think I did the top nut but missed the lower nut. I'll look at th at next . Yeah, I'm 60 and a little too big to get into that small of quarte rs. >> >> Hey Frank, thanks for the info too! >> >> I'm also looking at disconnecting the the main pressurizing line line at t he pressure reduction valve for the down stream items, after the nitrogen bo ttles, and capping off the line and then pressurizing the bottles. This shou ld tell me if there is a leak anywhere upstream of the reduction valve in th e main charging system. The emergency bottle holds pressure perfectly so no p roblems there. >> >> According to the service manual, the minimum loss is 5 atm over 2 hours. S o, I'm right on that limit at 2.5 atm per hour. >> >> Thanks! >> Tony >> >> >> >> >> >> On Thursday, March 24, 2016 7:15 PM, John Cabrera wrot e: >> >> >> I don=9Dt know if this is going to be of any help and some may laug h at me but i was chasing at leak in the rear canopy. Bought a fancy ultras onic leak detector and could not find any leak. Finally decided to check wi th old fashion soapy water and a spray bottle. That worked. >> >> John >> >> >> >> On Mar 23, 2016, at 8:22 AM, Anthony Royal wrote : >> >> Guys, my L-29 has always held nitrogen for days without much loss of pre ssure. Other day I pressurized to 140 atm because of a long flight and day. P ressure bled off immediately from 140 to about 90 atm before I could get out of the hangar. And was totally empty the next day. I found several loose, o riginal safety wired, connections not tight. Packing nut on the nitrogen pur ge valve was loose too. Tightened every fitting and thing I could find from n ose to rear cockpit. >> >> Now, if I pressurize to 50 atm, I will lose 30 atm in 12 hours. If I pres surize to 100 atm I lose 30 atm in 12 hours. Very consistent now. That's ab out 2.5 atm per hour. Any suggestions what else might cause such a consiste nt leak? Thinking maybe the pressure relief valve leaking? Check valve? Rea ding manuals and reviewing diagrams but thought maybe someone else may have r un into this same problem and save a lot of time >> >> Someone, in a post I can't find, suggested an ultrasonic tester of some s ort to detect high pressure leaks. Does anyone know which one it was? >> >> Also, looking for the glass lens for the taxi light. Rock must have hit m ineand cracked it in half. Glued it back but would like to replacement. Als o looking for connector to ARC EA-401A encoding altimeter. >> >> Thanks for any info >> >> Anthony >> >> ________________________________ Message 7 _____________________________________ Time: 07:53:35 PM PST US Subject: Re: L29-List: Nitrogen Loss From: migfighter42 V2hhdCB0eXBlIG9mIGFpciBjb21wcmVzc29yPyBBcmUgdGhleSBhdmFpbGFibGU/CgoKU2VudCBm cm9tIG15IFQtTW9iaWxlIDRHIExURSBEZXZpY2UtLS0tLS0tLSBPcmlnaW5hbCBtZXNzYWdlIC0t LS0tLS0tRnJvbTogSmVhbiBkZSBSb3ViaW4gPGRlbGZpbjI5QG1lLmNvbT4gRGF0ZTogMy8yNS8y MDE2ICAxMDozNiBQTSAgKEdNVC0wNTowMCkgVG86IGwyOS1saXN0QG1hdHJvbmljcy5jb20gU3Vi amVjdDogUmU6IEwyOS1MaXN0OiBOaXRyb2dlbiBMb3NzIApJIHRoaW5rIHRoZSBiZXN0IHdheSBp cyBhbiBhaXIgY29tcHJlc3Nvciwgd29ya2luZyBhdXRvbWF0aWNhbGx5IGF0IDIwIGJhcnMgYW5k IHN0b3BwaW5nIGF0IDUwLk15LCBpbnN0YWxsZWQgYnkgdGhlIHR6ZWNocyBhbmQgYXBwcm92ZWQg YnkgdGhlIGZhY3RvcnkgaXMgcGVyZmVjdGx5IHdvcmtpbmcgc2luY2UgMTUgeWVhcnMuIE5vIG5l ZWQgb2YgZ3JvdW5kIHN1cHBvcnQuSmVhbiBkZSBSb3ViaW4KCkVudm95w6kgZGUgbW9uIGlQaG9u 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ZW5zIGZvciB0aGUgdGF4aSBsaWdodC4gUm9jayBtdXN0IGhhdmUgaGl0IG1pbmVhbmQgY3JhY2tl ZCBpdCBpbiBoYWxmLiBHbHVlZCBpdCBiYWNrIGJ1dCB3b3VsZCBsaWtlIHRvIHJlcGxhY2VtZW50 LiDCoEFsc28gbG9va2luZyBmb3IgY29ubmVjdG9yIHRvIEFSQyBFQS00MDFBIGVuY29kaW5nIGFs dGltZXRlci7CoFRoYW5rcyBmb3IgYW55IGluZm/CoEFudGhvbnnCoMKg ________________________________ Message 8 _____________________________________ Time: 11:26:24 PM PST US From: Bill Geipel Subject: Re: L29-List: Nitrogen Loss Mine has been that way for 25 years. I converted everything, used the oxygen valve in the cockpit. When my brake pressure gets low, I open the valve and top it off. On Mar 25, 2016, at 13:07, Frank Deeth wrote: > I read once about an L-29 being operated in the UK where they disconnected the oxy system and plumbed those bottles into the pneumatic system, almost doubles the capacity if I recall...? Has anyone else looked at doing that? > > Frank > > Sent from my iPad > > On Mar 26, 2016, at 4:20 AM, Bill Culberson wrote: > >> Ultrasonic leak detector only works on the high pressure leaks (75-100 BAR), as it detects the specific audio signature of high pressure gas escaping. Canopy seals and brakes are at lower pressures and the soap and water test seems best. >> >> I don=92t use a Schrader valve but rather the original quarter turn valve but recently converted the N2 Cover to having a Schrader adapter =93just in case=94. My plane doesn=92t leak much but discovered that with the cover changed and a good gasket the N2 cover that the N2 remains for weeks instead of days. Main check valve must be leaking. >> >> I like the Hand valve at the tanks, what did you use? Pics? >> >> Bill >> N39DE >> >> From: owner-l29-list-server@matronics.com [mailto:owner-l29-list-server@matronics.com] On Behalf Of Jorgen Nielsen >> Sent: Friday, March 25, 2016 2:52 AM >> To: l29-list@matronics.com >> Subject: RE: L29-List: Nitrogen Loss >> >> I also tried an ultrasonic leak detector, got a very expensive version on trial for a week from a specialty supplier. Could not find anything using it either. Soapy water is messy but seems to work best. >> >> My air system is modified, with a hand valve installed close to the bottles. When I am done flying, I shut it off. Also nice if using the L29 to go somewhere, turn it off after landing, turn it back on before flight, no losses. >> >> From: owner-l29-list-server@matronics.com [mailto:owner-l29-list-server@matronics.com] On Behalf Of Anthony Royal >> Sent: Friday, 25 March 2016 02:17 >> To: l29-list@matronics.com >> Subject: Re: L29-List: Nitrogen Loss >> >> Hey guys, >> Thanks for all your suggestions! John, I did the soapy water test on every fitting I could find all the way back to the fittings for the emergency bottle and beyond. ...tightened too. No Joy. >> >> Bill, I think I did the top nut but missed the lower nut. I'll look at that next . Yeah, I'm 60 and a little too big to get into that small of quarters. >> >> Hey Frank, thanks for the info too! >> >> I'm also looking at disconnecting the the main pressurizing line line at the pressure reduction valve for the down stream items, after the nitrogen bottles, and capping off the line and then pressurizing the bottles. This should tell me if there is a leak anywhere upstream of the reduction valve in the main charging system. The emergency bottle holds pressure perfectly so no problems there. >> >> According to the service manual, the minimum loss is 5 atm over 2 hours. So, I'm right on that limit at 2.5 atm per hour. >> >> Thanks! >> Tony >> >> >> >> >> >> On Thursday, March 24, 2016 7:15 PM, John Cabrera wrote: >> >> >> I don=94t know if this is going to be of any help and some may laugh at me but i was chasing at leak in the rear canopy. Bought a fancy ultrasonic leak detector and could not find any leak. Finally decided to check with old fashion soapy water and a spray bottle. That worked. >> >> John >> >> >> >> On Mar 23, 2016, at 8:22 AM, Anthony Royal wrote: >> >> Guys, my L-29 has always held nitrogen for days without much loss of pressure. Other day I pressurized to 140 atm because of a long flight and day. Pressure bled off immediately from 140 to about 90 atm before I could get out of the hangar. And was totally empty the next day. I found several loose, original safety wired, connections not tight. Packing nut on the nitrogen purge valve was loose too. Tightened every fitting and thing I could find from nose to rear cockpit. >> >> Now, if I pressurize to 50 atm, I will lose 30 atm in 12 hours. If I pressurize to 100 atm I lose 30 atm in 12 hours. Very consistent now. That's about 2.5 atm per hour. Any suggestions what else might cause such a consistent leak? Thinking maybe the pressure relief valve leaking? Check valve? Reading manuals and reviewing diagrams but thought maybe someone else may have run into this same problem and save a lot of time >> >> Someone, in a post I can't find, suggested an ultrasonic tester of some sort to detect high pressure leaks. Does anyone know which one it was? >> >> Also, looking for the glass lens for the taxi light. Rock must have hit mineand cracked it in half. Glued it back but would like to replacement. Also looking for connector to ARC EA-401A encoding altimeter. >> >> Thanks for any info >> >> Anthony ________________________________ Message 9 _____________________________________ Time: 11:27:38 PM PST US From: Bill Geipel Subject: Re: L29-List: Nitrogen Loss send description and pix. On Mar 25, 2016, at 20:36, Jean de Roubin wrote: > I think the best way is an air compressor, working automatically at 20 bars and stopping at 50. > My, installed by the tzechs and approved by the factory is perfectly working since 15 years. No need of ground support. > Jean de Roubin > > Envoy=E9 de mon iPhone > > Le 25 mars 2016 =E0 19:58, Frank Deeth a =E9crit : > >> Thanks Jorgen! >> >> Sent from my iPhone >> >> On 26 Mar 2016, at 6:50 AM, Jorgen Nielsen wrote: >> >>> Mine is also done like that. I only posted half the story earlier, herewith then the full story J >>> >>> I don=92t use oxygen, so repurposed the tanks. >>> >>> My oxygen tanks have a tap on them, close to the bottles, and a pressure gauge. The tap & gauge is situated in the nose compartment. >>> My normal air bottle (N2) also have a tap on them, and a gauge, also in the nose compartment. >>> So far, 2 separate systems. >>> After the taps, they are interconnected via a T, output goes to the air system. >>> >>> Benefits: >>> Closing the valves means no leaks when she is standing. >>> Having the 2 systems that close means I can go away for a weekend with no ground support, or for example a 3 hop ferry I did a while back. At the destination, close the active system. For the next flight, pick a system and open valve. When the system is empty use the next one. >>> >>> To fill, if its just a normal flight from home base, I open the valve for whichever system is in use, and fill normally. For extended flights, one can fill one system at a time, or open both and fill both, then close one. >>> >>> So far, completely trouble free for a number of years. >>> >>> I will have to take some pics when at the airport. I used spare hand operated valves, similar to the pressure release inside the cockpit. I never did the work myself, I have a Russian guy who does all my maintenance, I just dreamt it up and asked him to do it. >>> >>> Another mod we did: my front / rear braking system has been reversed. I was once taxying with pax, and asked them to hold the brake while I did something. On release, when I took over, suddenly I had no brakes, and no steering obviously. We almost went farming. In normal ops, the rear brake is for the instructor, and held a certain way can disable the front cabin system. Not good for how we operate them privately. >>> >>> Regards to all >>> Jorgen >>> >>> From: owner-l29-list-server@matronics.com [mailto:owner-l29-list-server@matronics.com] On Behalf Of Frank Deeth >>> Sent: Friday, 25 March 2016 21:07 >>> To: l29-list@matronics.com >>> Subject: Re: L29-List: Nitrogen Loss >>> >>> I read once about an L-29 being operated in the UK where they disconnected the oxy system and plumbed those bottles into the pneumatic system, almost doubles the capacity if I recall...? Has anyone else looked at doing that? >>> >>> Frank >>> >>> Sent from my iPad >>> >>> On Mar 26, 2016, at 4:20 AM, Bill Culberson wrote: >>> >>> Ultrasonic leak detector only works on the high pressure leaks (75-100 BAR), as it detects the specific audio signature of high pressure gas escaping. Canopy seals and brakes are at lower pressures and the soap and water test seems best. >>> >>> I don=92t use a Schrader valve but rather the original quarter turn valve but recently converted the N2 Cover to having a Schrader adapter =93just in case=94. My plane doesn=92t leak much but discovered that with the cover changed and a good gasket the N2 cover that the N2 remains for weeks instead of days. Main check valve must be leaking. >>> >>> I like the Hand valve at the tanks, what did you use? Pics? >>> >>> Bill >>> N39DE >>> >>> From: owner-l29-list-server@matronics.com [mailto:owner-l29-list-server@matronics.com] On Behalf Of Jorgen Nielsen >>> Sent: Friday, March 25, 2016 2:52 AM >>> To: l29-list@matronics.com >>> Subject: RE: L29-List: Nitrogen Loss >>> >>> I also tried an ultrasonic leak detector, got a very expensive version on trial for a week from a specialty supplier. Could not find anything using it either. Soapy water is messy but seems to work best. >>> >>> My air system is modified, with a hand valve installed close to the bottles. When I am done flying, I shut it off. Also nice if using the L29 to go somewhere, turn it off after landing, turn it back on before flight, no losses. >>> >>> From: owner-l29-list-server@matronics.com [mailto:owner-l29-list-server@matronics.com] On Behalf Of Anthony Royal >>> Sent: Friday, 25 March 2016 02:17 >>> To: l29-list@matronics.com >>> Subject: Re: L29-List: Nitrogen Loss >>> >>> Hey guys, >>> Thanks for all your suggestions! John, I did the soapy water test on every fitting I could find all the way back to the fittings for the emergency bottle and beyond. ...tightened too. No Joy. >>> >>> Bill, I think I did the top nut but missed the lower nut. I'll look at that next . Yeah, I'm 60 and a little too big to get into that small of quarters. >>> >>> Hey Frank, thanks for the info too! >>> >>> I'm also looking at disconnecting the the main pressurizing line line at the pressure reduction valve for the down stream items, after the nitrogen bottles, and capping off the line and then pressurizing the bottles. This should tell me if there is a leak anywhere upstream of the reduction valve in the main charging system. The emergency bottle holds pressure perfectly so no problems there. >>> >>> According to the service manual, the minimum loss is 5 atm over 2 hours. So, I'm right on that limit at 2.5 atm per hour. >>> >>> Thanks! >>> Tony >>> >>> >>> >>> >>> >>> On Thursday, March 24, 2016 7:15 PM, John Cabrera wrote: >>> >>> >>> I don=94t know if this is going to be of any help and some may laugh at me but i was chasing at leak in the rear canopy. Bought a fancy ultrasonic leak detector and could not find any leak. Finally decided to check with old fashion soapy water and a spray bottle. That worked. >>> >>> John >>> >>> >>> >>> On Mar 23, 2016, at 8:22 AM, Anthony Royal wrote: >>> >>> Guys, my L-29 has always held nitrogen for days without much loss of pressure. Other day I pressurized to 140 atm because of a long flight and day. Pressure bled off immediately from 140 to about 90 atm before I could get out of the hangar. And was totally empty the next day. I found several loose, original safety wired, connections not tight. Packing nut on the nitrogen purge valve was loose too. Tightened every fitting and thing I could find from nose to rear cockpit. >>> >>> Now, if I pressurize to 50 atm, I will lose 30 atm in 12 hours. If I pressurize to 100 atm I lose 30 atm in 12 hours. Very consistent now. That's about 2.5 atm per hour. Any suggestions what else might cause such a consistent leak? Thinking maybe the pressure relief valve leaking? Check valve? Reading manuals and reviewing diagrams but thought maybe someone else may have run into this same problem and save a lot of time >>> >>> Someone, in a post I can't find, suggested an ultrasonic tester of some sort to detect high pressure leaks. Does anyone know which one it was? >>> >>> Also, looking for the glass lens for the taxi light. Rock must have hit mineand cracked it in half. Glued it back but would like to replacement. Also looking for connector to ARC EA-401A encoding altimeter. >>> >>> Thanks for any info >>> >>> Anthony ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message l29-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/L29-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/l29-list Browse Digests http://www.matronics.com/digest/l29-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.