Help Needed on electric Gear Issue - different problem

[TTaylor]

I have a question about the electric gear but a different issue. Mooney 20F 1975.

When climbing out of Ketchum, Oklahoma on Saturday I switched the gear selector up and got the gear unsafe light and the green gear down light at the same time. The gear did not move. I pressed the gear over-ride button and the gear then moved normally.

It appears that either a switch or relay is stuck or the squat switch is stuck to not allow movement in the opposite direction. Anyone have experience with this and where to start trouble shooting?

The wiring diagram I have in the back of my manual is titled POK134500 ( Wiring diagram SCI-800269L-2) and dated 1989. Not sure if it correct for the 1975 20F.

[Jeev]

Make sure the latch over the emergency gear extension lever between the front seats is latched down as it can sometimes be knocked by passengers. I figured this out after the same experience :-)

[Marauder]

I have a question about the electric gear but a different issue. Mooney 20F 1975.

When climbing out of Ketchum, Oklahoma on Saturday I switched the gear selector up and got the gear unsafe light and the green gear down light at the same time. The gear did not move. I pressed the gear over-ride button and the gear then moved normally.

It appears that either a switch or relay is stuck or the squat switch is stuck to not allow movement in the opposite direction. Anyone have experience with this and where to start trouble shooting?

The wiring diagram I have in the back of my manual is titled POK134500 ( Wiring diagram SCI-800269L-2) and dated 1989. Not sure if it correct for the 1975 20F.

How cold is it where you are and how long ago was the plane flown? Our planes did not originally come equipped with the gear override switch. They were installed on later models and many of us installed them afterwards. The problem with cold weather ops or letting it sit a long time is with the donuts. Our model uses a squat switch to let the gear system know the gear is down. When you take off, the donuts expand allowing the switch to activate. When it is really cold or you let it sit for a long time, the donuts don't expand and you get this indication.

I flew for years in upstate NY without the override switch. And although I had fresh donuts on it and I flew regularly, I would have this happen enough that I installed the override switch.

[tyrefoote]

Check to see if your model has the airspeed safety switch behind the airspeed indicator instead of a convenntional squat switch. If it does, It may need calibrated or you may not have had enough airspeed ram presure to open the switch contacts. Hope this helps. Ty

[Marauder]

Check to see if your model has the airspeed safety switch behind the airspeed indicator instead of a convenntional squat switch. If it does, It may need calibrated or you may not have had enough airspeed ram presure to open the switch contacts. Hope this helps. Ty

If this this is the same plane (N6847V) that I am thinking about, he will have the mechanical squat switch. The airspeed switch as far as I can recall were installed on J and newer. There may have been some 76/78 non J versions with the airspeed switch, but I don't think so.

[Mikey30V]

My 1975 C experienced the same problem in cold weather when I was based in Davenport Iowa. The shock discs had lost resilience at low temperatures, so they failed to keep the squat switch on the left gear leg actuated during gear operation. Once the airplane was in the hangar the gear would never fail to function.

After changing the shock discs, no more problems. So far I have not had to install the override push button as Marauder has done.

[DanM20C]

If this this is the same plane (N6847V) that I am thinking about, he will have the mechanical squat switch. The airspeed switch as far as I can recall were installed on J and newer. There may have been some 76/78 non J versions with the airspeed switch, but I don't think so.

My 69 C has the airspeed switch. As far as I know it is original.

Dan

[Marauder]

My 69 C has the airspeed switch. As far as I know it is original.

Dan

Dan -- is your Mooney considered an "Aerostar" generation Mooney? Wonder if they went back and forth between the two designs. Where is you airspeed switch connected? 47V, the plane on this post is covered in my manuals for the 1975 model year. I think the manual goes back a few years. Now I'm curious if others have different configurations.

[TTaylor]

I don't see an airspeed switch in any of my diagrams. My guess it is the squat switch. Mine has not been flown for five years so either the shocks have compressed or the switch is sticky. I cleaned all the limit switches but did not look for the squat switches during the annual.

Tim

[Marauder]

I don't see an airspeed switch in any of my diagrams. My guess it is the squat switch. Mine has not been flown for five years so either the shocks have compressed or the switch is sticky. I cleaned all the limit switches but did not look for the squat switches during the annual.

Tim

Tim, the squat switch will be physically touching the top of the housing that contains the main gear donut. I believe it is on the left main gear. I'm pretty sure you have a squat not an airspeed switch. Your serial number should be in th 22-12XX range. Let me pull the service manual out and see if I can confirm where it is.

[Marauder]

Tim -- I found the section on the squat switch. It is on the left main. Interesting, it does appear that they did go back and forth between airspeed and squat switches before the J models. I am scanning the pages pertaining to these switches and will email them to you. If you need the entire gear section, let me know. I can scan it for you.

With the plane sitting for 5 years, you will want to keep an eye on the donuts. There is a numerical code on them that tell you the year they were made.

[Marauder]

Tim -- I have scanned the pages and will send them to you via email. I have also copied Mooney Service Bulletin 196 that discusses the by-pass switch. Our vintage planes did not come with that switch, it was made available as a kit from Mooney and many of us, especially in the colder climates installed them.