MReitz Posted August 19, 2015 Report Posted August 19, 2015 I have a 1980 M20J that had a Plane Power Alternator installed in it before I purchased the aircraft. It still has the same voltage regulator and my mechanics are having hell getting the voltage to stay between 13.0 and 14.5. I am getting very erratic swings on my ammeter (from -30 to +30) and it seems to be making my autopilot porpoise pretty bad. I had the Century 41 AP rebuilt and that did not resolve the issue. I am convinced that it is an issue between the voltage regulator and the alternator, so I purchased the Plane Power voltage regulator that is supposedly compatible. Apparently the M20J model is not listed on the approved airplanes for this regulator, so the plane will be grounded pending an FAA Field Approval. This is a crock of crap because the M20F IS a listed approved plane and that is pretty much the same aircraft, correct?? Has anyone had these issues or tried installing this voltage regulator on the J model? I would appreciate any feedback I can get from you pro's. Thanks, Michael Reitz 1980 M20J N3891H Quote
mooniac15u Posted August 19, 2015 Report Posted August 19, 2015 Have you checked with Mooney to see if it is on their approved list? The parts catalog says, "Refer to MAC retrofit dwg 940125 for replacement 14V voltage regulators." Quote
MReitz Posted August 19, 2015 Author Report Posted August 19, 2015 I have tried but havent been able to reach them. Will keep trying. Thanks Quote
KSMooniac Posted August 19, 2015 Report Posted August 19, 2015 Go for the Zef unit! Sent from my VS985 4G using Tapatalk Quote
AndyFromCB Posted August 19, 2015 Report Posted August 19, 2015 Canon plug from mouser and a hangar fairy is all that's needed to install the plane power unit ;-) I fixed my Zeftronics unit on my Bravo 4 years ago, but I do carry a spare plane power unit (actually two, wired for my Bravo in case it dies again in remote location... Quote
MReitz Posted August 19, 2015 Author Report Posted August 19, 2015 Hopefully Don is right about this, but I have had 3 different mechanics look at the wiring and all say that it is good. I guess the next route is to actually test it in flight, because the ammeter rarely swings on the ground. Still think I will go with the Zef unit in hopes that i can maintain a voltage around 13.7 or so. Hopefully it will fix my porpoising issue, but Don did not seem to optimistic about that, and he is a mooney god... http://www.donmaxwell.com/publications/MAPA_TEXT/Fluctuating%20Ammeters/Fluctuating%20Ammeters.htm Quote
M016576 Posted August 19, 2015 Report Posted August 19, 2015 Your J is beautiful! Hope the problem is resolved quickly. Other possible issues: loose grounding wire, switch or circuit breaker going bad (master or avionics master), wire grounding out on another system causing erratic voltage (landing light, radio, etc). I'd start at the grounding bars, circuit breakers and switches under the panel with a can of contact cleaner and a file looking for corrosion and go from there. The voltage regulator is another option... But it sounds more like a loose ground or bad connection, since the ammeter is swinging negative as well as positive... Did this issue just appear? If so the corrosion factor could certainly be at play (vice the VR which would probably show right after the install on the alternator if it wasn't compatible). Those autopilots are very sensitive to voltage swings- you're on the right track imo. Disclaimer- I'm not an A&P. Just seen a few electrical issues in cars, boats and planes. Edit- just read that maxwell link- apparently he agrees- commonly the issue is corrosion on the switch terminals. Please let us know what you find out. Quote
MReitz Posted August 20, 2015 Author Report Posted August 20, 2015 I am still having trouble finding the correct voltage regulator (or at least one that specifically lists the M20J) The zef VR says that the compatible aircraft are the MOONEY: M20, M20A, M20B, M20C, M20D, M20E, M20F, M20G (i didn't even know there was an M20D). I have had 4 A&P's check all wiring, grounds, master switches, breakers, etc and none have been able to get a handle on it yet because it rarely does it on the ground. I am having the master switch replaced now as possibly it could be inside the switch. hopefully that works, but we shall see. Quote
mooniac15u Posted August 20, 2015 Report Posted August 20, 2015 The R15300 has the J listed. http://www.aircraftspruce.com/catalog/eppages/zeftronicsreg.php Quote
OR75 Posted August 20, 2015 Report Posted August 20, 2015 There are two possibilities from Zeftronics the R15300 and the R1530B. Both are PMA'ed parts. the difference is the type of plug: one is plastic and other is steel check the type of plug you have currently and choose accordingly Quote
mooniac15u Posted August 20, 2015 Report Posted August 20, 2015 There are two possibilities from Zeftronics the R15300 and the R1530B. Both are PMA'ed parts. the difference is the type of plug: one is plastic and other is steel check the type of plug you have currently and choose accordingly The R1530B doesn't appear to specifically list the J. Quote
OR75 Posted August 20, 2015 Report Posted August 20, 2015 it is FAA PMA and replaces the following parts: Mooney P/N: 880016-501 OECO 20082, 200655, etc ... on the early Js, MAC installed both the 880016-501 , 880016-503, and others brands ... OECOs, etc .... (the voltage regulator is one of the most difficult part to find in the Mooney. Eventually I found it above the co-pilot feet I don't know which one has a plastic plug and which one has a steel plug I think -503 has the plastic plug and the -501 has the steel one check what you have, use a PMA'ed replacement and logbook entry required for the R&R Quote
mooniac15u Posted August 20, 2015 Report Posted August 20, 2015 The FAA PMA for the R1530B doesn't list M20J and the part number it replaces is not a Mooney part number. http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgpma.nsf/0/17F9E2297D2B4A5C8625759400684A36?OpenDocument Quote
OR75 Posted August 20, 2015 Report Posted August 20, 2015 the voltage regulators parts number is described in section 71-00-00 of the parts catalog 20082 is an OECO part number Quote
mooniac15u Posted August 20, 2015 Report Posted August 20, 2015 The PMA approval includes the eligible aircraft models. Quote
OR75 Posted August 20, 2015 Report Posted August 20, 2015 Not sure that has to be the case. If it is, I would have to remove my Concord 35-AXC battery - it is only listed for Pipers - not sure what I could use Quote
mooniac15u Posted August 20, 2015 Report Posted August 20, 2015 The PMA for the RG-35AXC was updated to include the M20J on 3/1/2005 (supplement 77). Quote
OR75 Posted August 20, 2015 Report Posted August 20, 2015 The latest version on the FAA website dated 02/10/2015 only lists Piper Quote
mooniac15u Posted August 20, 2015 Report Posted August 20, 2015 There are multiple entries on the FAA website for the RG-35AXC. The relevant information for Mooneys is here: http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgpma.nsf/0/C07AC498BE926620862575A10051ADD9?OpenDocument Quote
larryb Posted August 21, 2015 Report Posted August 21, 2015 My ammeter problem was the field wire terminal of the master switch. The rivet that attached the terminal to the switch was loose. New switch required. Quote
joepilot Posted August 22, 2015 Report Posted August 22, 2015 I have a '94 J & just went through elec issues. I replaced the alt (easy) with a Plane Power but did not totally fix the issue. Volt Reg was bad. I spoke with tech reps at both Zeph & Plane Power regarding their VR's. NEITHER has an STC for the newer J Mooneys! (I hate the FAA). My contacts said a field approval prob wouldn't happen. Had to get a new "Mooney" VR (I think made my Zeph?). Mooney price was, I forgot, $1600? And a 3 week back order. Luckily my shop had a new one on the shelf for somewhat cheaper. But not for the $350 price a VR should be! (I hate the FAA) -Joe Quote
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