flyby201

The boost pump switch on my 77 J isn’t working. It will not move to the on position. It’s like something inside the switch has broken and is blocking it from moving. The parts manual lists 4 different part numbers for a J model. Mine is supposed to be 930023-011. It seems that these switches are unavailable. Since these switches are also circuit breakers, what is everyone using as replacements? What is the difference between the one specified for my serial number versus the other 3? What is the amperage rating on the circuit breaker in these switches?

We've already removed the alternator and I've removed the stud just to look at it and see what it so special about it. Fairly easy to remove and replace. I just hope obtaining new studs aren't too difficult.

I didn’t discover this until late Friday afternoon and this being 4th of July weekend I won’t have a chance to source the studs until tomorrow. I’m going to call some of the companies that overhaul alternators and see if they will sell me a couple. If i have a problem finding them I had already thought of using washers temporarily or even using a new #6 bolt. The only thing I see special about the studs is that they have a carriage bolt design with a square section between the head and threads. But, in the end, I want it fixed correctly.

I sent an email to Zeftronics tech support and got a phone call the next day. The guy that called me had a VERY heavy foreign accent and I had trouble understanding him. He suggested I call Don Maxwell if I had questions. Don told me he gets at least one call per month about this problem and 99% of the time it is the ground wire on the field circuit at the alternator (bad connection at the terminal connectors). He said to replace this wire and it should resolve the problem. We removed the wire and it looked ok, terminal connectors appear to be solid but we made a new one anyway. We were putting it back on when we noticed the nut would not tighten all the way. Closer inspection revealed the threads on the terminal stud on F2 had worn away. I’m guessing that the nut loosened over time due to vibration and the washer and/or terminal connector wore away the threads. I’m waiting on new terminal studs and will advise if this fixes my problem. The problem with intermittent issues is that you don’t know if it’s fixed until it never happens again

I have a 77 201 and have been experiencing an intermittent electrical problem for some time. When this issue occurs, maybe every 3rd or 4th flight, the alternator will stop charging leaving the plane to operate on battery power. Usually when I notice this I can recycle the master switch a couple of times until it comes back online. Because it is so intermittent, it has been difficult for my A&P friends to diagnose. We attached a wire to the field wire connection at the alternator and ran it up into the cockpit. I attached a volt meter to it so I can monitor what is going on when this happens. (Trying to determine if the problem is the alternator or voltage regulator). Yesterday, I went to fly and during my run up on the ground I was turning on the landing light, pitot heat and anything else to put a load on the electrical system. During all this my field wire voltage was around 8 volts and bus voltage was around 14.1 volts. I looked away for a few seconds to attend to something else and when I looked back I had 0 volts on field wire and 12.3 volts on the bus. Recycling the master switch brought everything back to normal operation. I haven't had a chance to share this information with my A & Ps but wanted to put this info on MooneySpace to see what the consensus was here. Your input will be greatly appreciated.

I have a 77 J (SN 24-0014). It appears the left outboard fuel transmitter is leaking. My parts manual gives me a part number of 610243-003, but says that is for SN 24-3133 and later. It doesn't give a part number for my SN. Anyone know what the correct part number would be? What are my options to have it overhauled?

Thanks to all for the input. I’m hoping Andy95W’s link to Don Maxwell’s article hits the nail on the head. He mentions in the article that this is a common problem on early J models. Mine is serial number 24-0014 so I think that qualifies as an early J model. I do remember yesterday during my flight reaching under the master switch and wiggling the wires connected to the master switch. Maybe I wiggled enough corrosion off of them to make a better connection and that’s why it worked later when I turned it back on. I’ll get in there tomorrow and give all the connections a good cleaning. As intermittent as this has been it may be a year or more before I know if it fixed it.

I am having an intermittent electrical issue in my 77 M20 J. This problem first appeared about a year ago. After take off I will get a low battery alert on my EDM-700. Last October I was on my way home in the middle of nowhere so I decided to turn off my master and fly home, saving my battery juice for talking to the tower and lowering the gear at arrival. Then, 3/4 of the way home I was skirting a class C area and turned on the master to talk to ATC and everything was working fine, battery showing 14+ volts. My A&P and I investigated the issue, checked the alternator and associated wiring and all check as ok. Subsequent flights went off without any problems so we thought we might have inadvertently and unknowingly fixed the problem with our alternator checks, I.e.; tightened a loose connection. Then, yesterday, the problem raised its ugly head. Same scenario, low voltage alert on take off, then 50 miles from home turn on the master and all working as advertised. I hate to start throwing money at the problem, but I don’t know what else to do. We have a service manual but it is lacking a wiring diagram. I was thinking faulty master switch but everything else connected to the master works, it just doesn’t charge the battery. Could it be a bad master relay at the battery? I’m looking for any help/ knowledge about how to approach this problem. Thanks in advance. Steve Beckerdite N201HL

I have noticed that some members have maps attached to their profiles which show which states they have flown to. How does one get that? Steve

CLEAN, LOW TIME, M20J FOR SALE. 1977 Mooney M20J. $92,000 (Priced below Vref). 2477 Hr TT 375 HR SMOH by Mena AIrcraft Engines 375 Hr SNEW Hartsell Scimitar Prop White with 2 tone blue accents. Paint in good condition Blue leather interior in good condition K & N Air filter Concorde Battery New Shock discs, 2015 Annual due October, 2017 IFR due January 2018 Avionics: Garmin GNS-480 GPS/NAV/COM S-TEC 50 Autopilot with altitude hold couples to GPS with GPSS Eleictric trim GI-106 CDI EDM-700 Engine analyzer with fuel flow 2- Bose X Noise cancelling headsets Collins VHF-251 COM Collins VIR-351 NAV Collins TDR-950 Transponder Collins AMR-350 Audio Panel Sigtronics SP-400 4 place intercom w/ Music input NOTE: Yoke mounted GPS in photo not included.

Does anyone know if there is a way to adjust the volume of the stall horn? I don't know if it's my advancing age or what but it seems like I'm not hearing it lately. I was doing stalls the other day during a BFR and it wasn't loud enough that it would grab my attention if I even got into an inadvertent stall.

Its annual time and we are installing new gear shock discs. Can anyone direct me to detailed instructions for doing the main gears. The nose gear was easy but my A&P and I scratched almost all the hair off our heads trying to figure out how to do the mains. Specifically, how to remove the bolt at the top of the spindle that holds the discs. There is zero clearance to get wrenches on the head of the bolt and the nut and when you can finally get a wrench on it there is no room to move the wrench. The Mooney service manual is very vague on this procedure. Any help would be greatly appreciated.

My procedure on my 201 is slightly different. Throttle 1/4 - 1/2", prop full, mixture closed. Boost pump on for 5 sec, Fuel press = 25, boost off. mixture full rich (fuel pressure falls, of course), then crank. After starting adjust mixture for ground ops. Never have starting problems with this procedure. I also have the Concorde battery

I have a 1977 J model and I am flying to Houston in 2 weeks with my son. We need to bring 2 bicycles (road bikes) with us. I've done this trip by myself with one bike... no problem, but I'm thinking I may not be able to get 2 bikes in there. I remove the wheels and put them in the luggage compartment and put the frame on the back seat. I'm wondering if the back seat is removable. I know the seat bottom comes out fairly easily, but I'm wondering about the seat back. Back when I first bought it an A & P friend and I were going to Oshkosh with a LOAD of camping stuff. We discussed removing the back seat then but he was concerned that the plane might not have been "approved" to fly without it. (Thinking the rod across the top of the backseat might be a structural component of the aircraft). Anyone know anything about this? Steve N201HL

This sounds like a problem I'm having, high oil temps, slightly low oil pressure. I've talked to my A&P about this after reading above. I don't think he's up to speed on vernatherms, said they could not be adjusted. Can you tell me how, or give me a reference for, how to test and adjust it?