---------------------------------------------------------- L29-List Digest Archive --- Total Messages Posted Thu 03/24/16: 2 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:12 PM - Re: Nitrogen Loss (John Cabrera) 2. 05:20 PM - Re: Nitrogen Loss (Anthony Royal) ________________________________ Message 1 _____________________________________ Time: 04:12:08 PM PST US From: John Cabrera Subject: Re: L29-List: Nitrogen Loss 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: 05:20:19 PM PST US From: Anthony Royal Subject: Re: L29-List: Nitrogen Loss Hey guys,Thanks for all your suggestions! =C2-John, I did the soapy water test on every fitting I could find all the way back to the fittings for th e 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 quarter s. Hey Frank, thanks for the info too! I'm also looking at disconnecting the the main pressurizing line line at th e pressure reduction valve for the down stream items, after the nitrogen bo ttles, and capping off the line and then pressurizing the bottles. This sho uld 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 wr ote: 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. =C2-Bought a fancy u ltrasonic leak detector and could not find any leak. =C2-Finally decided to check with old fashion soapy water and a spray bottle. =C2-That worked . =C2- John On Mar 23, 2016, at 8:22 AM, Anthony Royal wrote: Guys, =C2-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 d ay. Pressure bled off immediately from 140 to about 90 atm before I could g et out of the hangar. =C2-And was totally empty the next day. I found sev eral loose, original safety wired, connections not tight. Packing nut on th e nitrogen purge valve was loose too. Tightened every fitting and thing I c ould find from nose to rear cockpit. =C2- Now, if I pressurize to 50 atm, I will lose 30 atm in 12 hours. If I pressu rize to 100 atm I lose 30 atm in 12 hours. Very consistent now. =C2-That' s about 2.5 atm per hour. =C2-Any suggestions what else might cause such a consistent leak? Thinking maybe the pressure relief valve leaking? Check valve? =C2-Reading manuals and reviewing diagrams but thought maybe someo ne 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 sor t 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 min eand cracked it in half. Glued it back but would like to replacement. =C2 -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.