---------------------------------------------------------- Yak-List Digest Archive --- Total Messages Posted Sun 02/06/11: 3 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:36 PM - Yak 52 / M14P documentation (Bill VonDane) 2. 04:34 PM - Re: Yak 52 / M14P documentation (Eric Wobschall) 3. 08:42 PM - Re: Voltage Regulation LONG REPLY! (lesknox) ________________________________ Message 1 _____________________________________ Time: 12:36:33 PM PST US From: Bill VonDane Subject: Yak-List: Yak 52 / M14P documentation Hey all... I am hoping maybe someone on this list can help with some info... What I need is documentation that shows the Russian overhaul requirements / times...something that actually lists times and maintenance / overhaul requirements for the Yak 52 and the Russian M14P engine... If that doesn't make sense please drop me a line... Thanks! -Bill ________________________________ Message 2 _____________________________________ Time: 04:34:00 PM PST US Subject: Re: Yak-List: Yak 52 / M14P documentation From: Eric Wobschall Bill: There are experts on here who have been to the factory, but there may not be a definitive answer to the traditional Western need for TBOs and overhaul specifications for a few reasons: These engines are used in radically different situations (unlimited akro at full power, training, and milder applications). The maintenance regime in the Eastern Bloc is also way different. Depending on what the engine was being used for, apparently it was directed that they be returned to an overhaul facility for IRAN (inspect and repair as needed) at different intervals. I have heard that these times (in hours) were low compared to a typical TBO, but you also weren't going to replace so many components the way we would over here. So they weren't as thorough with replacing / machining / overhauling all of the parts, but the engines were being torn down and inspected more frequently. I guess this is analogous to a progressive inspection program on a Western airplane. This is a tear-down inspection I'm referring to. On the other hand, the planes weren't being subjected to annual condition inspections the way we do. Whether the engine was first, second or third run (new, overhauled once, overhauled twice) affected the IRAN interval. I say overhauled, which is like our overhaul, not just an IRAN. Apparently, the oil over there wasn't as good as here. If you contact the pros on here (Coy, Goode, Hayes, Sapp, Savarese) and describe your circumstances, they will give you an idea of what to expect. Anyway, a lot of documentation for the Yak-52 and M-14P is available on PDF contact me off-list if you need it. -Eric On Feb 6, 2011, at 3:31 PM, Bill VonDane wrote: > > Hey all... > > I am hoping maybe someone on this list can help with some info... > What I need is documentation that shows the Russian overhaul > requirements / times...something that actually lists times and > maintenance / overhaul requirements for the Yak 52 and the Russian > M14P engine... > > If that doesn't make sense please drop me a line... > > Thanks! > -Bill > > > > ________________________________ Message 3 _____________________________________ Time: 08:42:29 PM PST US Subject: Yak-List: Re: Voltage Regulation LONG REPLY! From: "lesknox" The aircraft is a Yak-52, standard electrics. Observation/ symptoms were: Over voltage button IN After start, GEN light on at idle, 24V As the rpm is increased, GEN light extinguishes, >24V Further rpm increase gives a fairly linear increase in volts When volts just above 30, GEN light on, amps drop The over-voltage button has now "popped". Varying the cockpit regulator adjustment has no effect. After getting as much info as I could, it was time to try and find the problem The Voltage Regulator is quite obvious when you know roughly where and what to look for. In the 52, it is in a recess in the front cockpit floor, forward left side, near the firewall. It is not easy to reach (seat needs to come out) and clips holding it to the shock mount are difficult both to remove and reattach. A thin person and long pliers seem to help. Maybe there is better technique. After a quick look at the reg itself, I decided to check the wiring leading to the mounting plate. They seemed to be intact and secure. Next I removed the cockpit voltage adjustment rheostat. This is, again, difficult because you need to remove all the screws on the console on the left side. They don't make gadgets like that anymore. The connectors seemed to have deteriorated a little (subsequently renewed). The pot itself seemed fine, with linear change in resistance. Only 0-6 Ohm. At this stage I checked the integrity of the circuit to the regulator mount and discovered that there was a break between the cockpit adjuster and the TC-9M-2 (which is I understand the Stabilizing Transformer and is the large coil like device top outboard quadrant in in the electrical system "grey box"). The applicable connection to the TC-9M-2 is the bottom inboard post and was the fault. It was not obvious because it was inside the insulating material of the ring connector. So the basic problem was a break in the voltage adjustment line. Replacing this connection might be the simplest first step in troubleshooting this problem because it is relatively accessible. Little bit of rewiring, then everything back where it belongs. Engine run carried out, with system performing as it should. Only took 8 hours in 40 degC heat! Still you learn things this way. Thanks to all who helped. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=329914#329914 ------------------------------------------------------------------------------------- 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.