---------------------------------------------------------- L29-List Digest Archive --- Total Messages Posted Wed 09/12/18: 7 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 11:03 AM - Re: weird bumping (thumping noise) sound from the Jet??? Help (skidmk) 2. 11:09 AM - Re: weird bumping (thumping noise) sound from the Jet??? Help (skidmk) 3. 11:16 AM - Re: Re: weird bumping (thumping noise) sound from the Jet??? Help (Anthony Royal) 4. 11:21 AM - Re: weird bumping (thumping noise) sound from the Jet??? Help (skidmk) 5. 11:36 AM - Re: Re: weird bumping (thumping noise) sound from the Jet??? Help (Delfin Driver) 6. 01:34 PM - Re: Re: weird bumping (thumping noise) sound from the Jet??? Help (William Geipel) 7. 11:06 PM - Re: Re: weird bumping (thumping noise) sound from the Jet??? Help (Bill Culberson) ________________________________ Message 1 _____________________________________ Time: 11:03:39 AM PST US Subject: L29-List: Re: weird bumping (thumping noise) sound from the Jet??? Help From: "skidmk" no change or variation in any engine parameters. -------- Mike "Skidmk" Bourget Ottawa, Ontario Read this topic online here: http://forums.matronics.com/viewtopic.php?p=483145#483145 ________________________________ Message 2 _____________________________________ Time: 11:09:22 AM PST US Subject: L29-List: Re: weird bumping (thumping noise) sound from the Jet??? Help From: "skidmk" Hey Dawg, Got the questions, we use oil from the can direct. Mobil. As for the thumping noises,, not really noticed at 80% or not. Most prevalent during take-off (100%) less so in cruise 85-90. It seems that it is getting more prevalent, up to and including the bumping on shut down this time. there is no variation in any op specs on the T's and P's. there is no evidence of flaming, or pop flames coming our of the tail. there is what I feel maybe more than normal soot on the tailcone (in the vicinity of the antenna's) what might you be thinking about the 80%? I will change the fuel filter tomorrow, aerate (bleed) the fuel system and see if that cures it. -------- Mike "Skidmk" Bourget Ottawa, Ontario Read this topic online here: http://forums.matronics.com/viewtopic.php?p=483146#483146 ________________________________ Message 3 _____________________________________ Time: 11:16:46 AM PST US From: Anthony Royal Subject: Re: L29-List: Re: weird bumping (thumping noise) sound from the Jet??? Help Have u cleaned the injectors? Had a thumping when power back in decent at 80-85%. Cleaned injectors and went away Sent from my iPhone > On Sep 12, 2018, at 2:09 PM, skidmk wrote: > > > Hey Dawg, > > Got the questions, we use oil from the can direct. Mobil. As for the thumping noises,, not really noticed at 80% or not. Most prevalent during take-off (100%) less so in cruise 85-90. It seems that it is getting more prevalent, up to and including the bumping on shut down this time. > > there is no variation in any op specs on the T's and P's. > > there is no evidence of flaming, or pop flames coming our of the tail. > > there is what I feel maybe more than normal soot on the tailcone (in the vicinity of the antenna's) > > what might you be thinking about the 80%? > > I will change the fuel filter tomorrow, aerate (bleed) the fuel system and see if that cures it. > > -------- > Mike "Skidmk" Bourget > Ottawa, Ontario > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=483146#483146 > > > > > > > > > ________________________________ Message 4 _____________________________________ Time: 11:21:22 AM PST US Subject: L29-List: Re: weird bumping (thumping noise) sound from the Jet??? Help From: "skidmk" yes sir ultrasonically cleaned, about 3 hours ago. symptoms went away for about 3 hours, and are now back with a vengeance. -------- Mike "Skidmk" Bourget Ottawa, Ontario Read this topic online here: http://forums.matronics.com/viewtopic.php?p=483148#483148 ________________________________ Message 5 _____________________________________ Time: 11:36:08 AM PST US From: Delfin Driver Subject: Re: L29-List: Re: weird bumping (thumping noise) sound from the Jet??? Help What exact oil are you using in the M701p? On September 12, 2018 13:11:53 "skidmk" wrote: > > Hey Dawg, > > Got the questions, we use oil from the can direct. Mobil. As for the > thumping noises,, not really noticed at 80% or not. Most prevalent during > take-off (100%) less so in cruise 85-90. It seems that it is getting more > prevalent, up to and including the bumping on shut down this time. > > there is no variation in any op specs on the T's and P's. > > there is no evidence of flaming, or pop flames coming our of the tail. > > there is what I feel maybe more than normal soot on the tailcone (in the > vicinity of the antenna's) > > what might you be thinking about the 80%? > > I will change the fuel filter tomorrow, aerate (bleed) the fuel system and > see if that cures it. > > -------- > Mike "Skidmk" Bourget > Ottawa, Ontario > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=483146#483146 > > ________________________________ Message 6 _____________________________________ Time: 01:34:03 PM PST US Subject: Re: L29-List: Re: weird bumping (thumping noise) sound from the Jet??? Help From: William Geipel Stock engine uses a mineral oil. Royco 481. (or Shell sp3 or 3sp, cant remember which) Mobile jet and 2380 are synthetic. May cause metal in your sample. Had several airplanes that rumbled around 80% never had any other issues. Is the thumping a metallic sound? Had one of those. Required new engine to stop the thumping. > On Sep 12, 2018, at 12:16, Anthony Royal wrote: > > > Have u cleaned the injectors? Had a thumping when power back in decent at 80-85%. Cleaned injectors and went away > > Sent from my iPhone > >> On Sep 12, 2018, at 2:09 PM, skidmk wrote: >> >> >> Hey Dawg, >> >> Got the questions, we use oil from the can direct. Mobil. As for the thumping noises,, not really noticed at 80% or not. Most prevalent during take-off (100%) less so in cruise 85-90. It seems that it is getting more prevalent, up to and including the bumping on shut down this time. >> >> there is no variation in any op specs on the T's and P's. >> >> there is no evidence of flaming, or pop flames coming our of the tail. >> >> there is what I feel maybe more than normal soot on the tailcone (in the vicinity of the antenna's) >> >> what might you be thinking about the 80%? >> >> I will change the fuel filter tomorrow, aerate (bleed) the fuel system and see if that cures it. >> >> -------- >> Mike "Skidmk" Bourget >> Ottawa, Ontario >> >> >> >> >> Read this topic online here: >> >> http://forums.matronics.com/viewtopic.php?p=483146#483146 >> >> >> >> >> >> >> >> >> > > > > > ________________________________ Message 7 _____________________________________ Time: 11:06:06 PM PST US From: Bill Culberson Subject: Re: L29-List: Re: weird bumping (thumping noise) sound from the Jet??? Help My previous L-29 would make that kind of noise (hollow thumping) at cruise settings 80-90% power. Not engine related, I believe it was just the inlet ducting. I inspected it numerous times and found no issues. Normal. Bill Culberson Red Star Aero Services 251/716/8119 > On Sep 12, 2018, at 3:22 PM, William Geipel wrote: > > > Stock engine uses a mineral oil. Royco 481. (or Shell sp3 or 3sp, cant remember which) Mobile jet and 2380 are synthetic. May cause metal in your sample. > > Had several airplanes that rumbled around 80% never had any other issues. > Is the thumping a metallic sound? Had one of those. Required new engine to stop the thumping. > > > > > >> On Sep 12, 2018, at 12:16, Anthony Royal wrote: >> >> >> Have u cleaned the injectors? Had a thumping when power back in decent at 80-85%. Cleaned injectors and went away >> >> Sent from my iPhone >> >>> On Sep 12, 2018, at 2:09 PM, skidmk wrote: >>> >>> >>> Hey Dawg, >>> >>> Got the questions, we use oil from the can direct. Mobil. As for the thumping noises,, not really noticed at 80% or not. Most prevalent during take-off (100%) less so in cruise 85-90. It seems that it is getting more prevalent, up to and including the bumping on shut down this time. >>> >>> there is no variation in any op specs on the T's and P's. >>> >>> there is no evidence of flaming, or pop flames coming our of the tail. >>> >>> there is what I feel maybe more than normal soot on the tailcone (in the vicinity of the antenna's) >>> >>> what might you be thinking about the 80%? >>> >>> I will change the fuel filter tomorrow, aerate (bleed) the fuel system and see if that cures it. >>> >>> -------- >>> Mike "Skidmk" Bourget >>> Ottawa, Ontario >>> >>> >>> >>> >>> Read this topic online here: >>> >>> http://forums.matronics.com/viewtopic.php?p=483146#483146 >>> >>> >>> >>> >>> >>> >>> >>> >>> >> >> >> >> >> > > > > > ------------------------------------------------------------------------------------- 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.