---------------------------------------------------------- Yak-List Digest Archive --- Total Messages Posted Mon 05/31/21: 3 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 08:40 AM - Compressor charging (1906) 2. 09:33 AM - Re: Compressor charging (Richard Goode) 3. 09:57 AM - Re: Compressor charging (1906) ________________________________ Message 1 _____________________________________ Time: 08:40:35 AM PST US Subject: Yak-List: Compressor charging From: "1906" I have flown behind two M14Ps recently and the pressure replenishment was different. One of them with less than 200 hours, the pressure system would charge during idle (40% RPM). On the other, with 620 hours, the pressure seemed to only charge in flight. Is this normal or will the compressor need replacement soon? Read this topic online here: http://forums.matronics.com/viewtopic.php?p=502155#502155 ________________________________ Message 2 _____________________________________ Time: 09:33:21 AM PST US From: "Richard Goode" Subject: RE: Yak-List: Compressor charging In our experience, the compressor is the weakest link in the M 14 engine, and many become much less effective in less than 500 hours. This is not helped since some, when overhauling the compressors simply put in new sets of piston rings rather than new cylinders which we feel are often required. This is an expensive exercise; cylinders and indeed new pistons can be difficult to find. But a good compressor will certainly charge at 40%, and I can totally understand that a worn compressor needs to be turning at higher rpm i.e. in flight to charge. Another very important point is that the compressor is working very hard simply because it is charging the system until the release-valve blows off; pressure reduces and then it starts working again. It is so much better to modify your aircraft and bring the water drain valve from the firewall into the cockpit with the water drain exit going through the floor of the aircraft. In this way you start the engine with the water drain firmly shut; after take off, the pressure builds up to its normal maximum, then you open the water drain and the compressor, although still operating is working totally off load and under dramatically less strain and will last far longer! RICHARD GOODE AEROBATICS Rhodds Farm, Lyonshall, Hereford, HR5 3LW, UK Tel: +44 (0)1544 340120 Fax: +44 (0)1544 340129 e-mail: richard.goode@russianaeros.com www.russianaeros.com WORLD LEADERS IN RUSSIAN SPORTING AIRCRAFT & ENGINES In partnership with Aerometal Kft, Hungary. -----Original Message----- From: owner-yak-list-server@matronics.com On Behalf Of 1906 Sent: 31 May 2021 16:40 Subject: Yak-List: Compressor charging I have flown behind two M14Ps recently and the pressure replenishment was different. One of them with less than 200 hours, the pressure system would charge during idle (40% RPM). On the other, with 620 hours, the pressure seemed to only charge in flight. Is this normal or will the compressor need replacement soon? Read this topic online here: http://forums.matronics.com/viewtopic.php?p=502155#502155 ________________________________ Message 3 _____________________________________ Time: 09:57:48 AM PST US Subject: Yak-List: Re: Compressor charging From: "1906" Thanks, Richard. These both have the compressor bypass (water drain as you call it) valve fitted already, but good info to know about the 500 hours. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=502159#502159 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message yak-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Yak-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/yak-list Browse Digests http://www.matronics.com/digest/yak-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.