Gear unsafe light

[1980Mooney]

1 hour ago, Kerrville said:

I need to pull everything apart now. Can’t find parts. Another airplane for the scrap heap?  

Here is another video showing the micro (stop) switches in action.  It has an Eaton actuator but the principle is the same.

 

[1980Mooney]

1 hour ago, Kerrville said:

I need to pull everything apart now. Can’t find parts. Another airplane for the scrap heap?  

Note in the "Bent Push Pull Rods"  Dec 15 2022 topic, that he used straight edges to check the rods without disassembly.

When you buy a Mooney, there can always be delays in parts.  Luckily there is a lot of scrap parts.  The factory does make parts....slowly.  And as @KSMooniac said a good A&P can repair a lot of parts.  I have owned a Mooney through bankruptcies and shutdowns.  The biggest delay I ever had was waiting on Rocket Engineering to repair my engine mount frame (unique to the Missile conversion).  Nowdays engine overhauls are taking longer than waiting for parts from Mooney.

[skykrawler]

When the gear extends the gear motor 'nut' (the tube on the jackscrew) should NOT bottom out against the motor transmission.  If it is, that could very well cause the breaker to pop.  Of course this the affect when the down switch is not closed.

 

[1980Mooney]

2 minutes ago, skykrawler said:

When the gear extends the gear motor 'nut' (the tube on the jackscrew) should NOT bottom out against the motor transmission.  If it is, that could very well cause the breaker to pop.

 

Remember that he has an early J with the Dukes actuator. I have no experience with it and don’t know if it differs from the Eaton.
 

[ArtVandelay]

Here is another video showing the micro (stop) switches in action.  It has an Eaton actuator but the principle is the same.
 

I’m surprised by the motor movement, would have thought it was rigidly mounted.

[N201MKTurbo]

4 minutes ago, ArtVandelay said:

I’m surprised by the motor movement, would have thought it was rigidly mounted.

All the actuators are mounted on a pivot. The actuator swings through the arc of the bell crank the actuator is actuating.

I just watched the video above. That actuator has a bent screw.

[PT20J]

37 minutes ago, N201MKTurbo said:

I just watched the video above. That actuator has a bent screw.

It also looks like one of the mechanical down stops is missing and the other one is bottoming out. And the nose gear doors don’t look tight when retracted.

[Guest]

5 hours ago, 1980Mooney said:

A clean “oh crap I completely forgot “ gear up generally does not tear up the rods, turnbuckles or actuator. It is the remembering and dropping the gear(partially extended)just as you touchdown, the porpoising nose gear collapse, the side skid collapse, and the improper gear rigging/weld crack collapse that tears up and bends everything in the landing gear system. 

It wasn’t a gear up, the prior owner sheared off the left main gear in a botched crosswind landing. Apparently the knowledgeable ia who did the repair wasn’t as knowledgeable as he thought…

[LANCECASPER]

Maxwells go out on airplane retrievals and sometimes bring them back on ferry permits. Talk to Don and see what they could do.

[Guest]

2 bent tubes. 

[EricJ]

Yes, those are bent, slightly. 

Bummer that it's turning into more than you expected, but it's still all fixable.

[PT20J]

I wonder if they are truly bent or just bowed under compression. It’s hard to tell from the angle of the photo.  Steel has a pretty high elastic limit and I don’t see any kinks. Probably a good idea to get it on jacks and get the load off and see. They might spring back into shape.

I don’t know if the Dukes-equipped planes have mechanical down stops. I don’t see them on the actuator or see reference in the service manual. The Eaton version can’t overdrive the gear by much due to the mechanical stops, but maybe the Dukes can which would make the whole thing depend on the down limit switch.

Anyone familiar with the Dukes know?

Skip

[Guest]

Hope they spring back, but that is probably too much to hope for. 
 

I can’t tell from this parts manual drawing what number the other tube is. One is 22, viz. 460225-501. The other doesn’t appear to be labeled. I can’t imagine they are the same. 

[kortopates]

I wonder if they are truly bent or just bowed under compression. It’s hard to tell from the angle of the photo.  Steel has a pretty high elastic limit and I don’t see any kinks. Probably a good idea to get it on jacks and get the load off and see. They might spring back into shape.
I don’t know if the Dukes-equipped planes have mechanical down stops. I don’t see them on the actuator or see reference in the service manual. The Eaton version can’t overdrive the gear by much due to the mechanical stops, but maybe the Dukes can which would make the whole thing depend on the down limit switch.
Anyone familiar with the Dukes know?
Skip

It takes quite a lot till they give and bow, But Once they bow, they’re gone. They’re very thin.


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[PT20J]

1 hour ago, Kerrville said:

I can’t tell from this parts manual drawing what number the other tube is. One is 22, viz. 460225-501. The other doesn’t appear to be labeled. I can’t imagine they are the same. 

Paul is most likely right about the tubes being permanently deformed, but if it were mine I would get the pressure off of them and see.

The tubes appear to be the same -- if you look at the Units/Assy column in the IPC for item 22 you'll see 2.

Skip

[1980Mooney]

4 hours ago, Kerrville said:

Hope they spring back, but that is probably too much to hope for. 
 

I can’t tell from this parts manual drawing what number the other tube is. One is 22, viz. 460225-501. The other doesn’t appear to be labeled. I can’t imagine they are the same. 

 

2 hours ago, PT20J said:

Paul is most likely right about the tubes being permanently deformed, but if it were mine I would get the pressure off of them and see.

The tubes appear to be the same -- if you look at the Units/Assy column in the IPC for item 22 you'll see 2.

Skip

I am confused by the part numbers mentioned here and on page three.

I think the control rods that are bent are 

• 550244-501
  •  That is the entire rod with rod ends on each end (including parts ARE-3-20 and F31-14MPB)
  • As Skip said there are "2" complete rods for the MLG
  • If you just want the tube without the rod ends it is part 560244-001
    • There is "1" tube within each complete entire rod

 

`The salvage yards get them confused and use then interchangeably.

Here is a BAS ad for the part number that is just the rod (out of stock -sorry) but you can see that it has the rod ends.

• They call it 560244-001
• https://baspartsales.com/560244-001-mooney-m20k-landing-gear-retract-rod-assembly/

[BlueDun]

On 12/14/2023 at 11:27 AM, Kerrville said:

I’ve got the belly pan off and I can see that the paddle is definitely not contacting the down limit switch. I wonder how it could have come off?  ...... 

I reset the gear actuator CB twice at my hangar before doing much research, so I imagine that the motor probably has overrun whatever limits it has and probably calls for a complete gear system rerig.  

Big problem is I now need someone to come to me. Is there any way to pin these gear so that it is safe to move?

I had a similar problem and am catching up on this thread. Will comment on other contributions where appropriate, including the shop that sourced parts and re-rigged. I think the problem was not caused by your bounce but more traumatic side loading, perhaps prior to your ownership. Gear actuator overrun probably bent your push-pull rods. That is going to be a pain. Took us awhile to find a new one for my install. 

[BlueDun]

On 12/14/2023 at 11:40 AM, Kerrville said:

Thanks for the encouragement. My Dad told me the first 3 years are going to be miserable. It’s to bad because on the now seemingly rare occasions when it flies, it is a lot of fun. Working on it is fun to. Figuring out what to do, not so much. 

Mine is an 06 Ovation 3. It was in great shape and I got a good, thorough pre-buy and expensive first annual. I am happy butnhave been fixing amazing issue for 3 years. There is light at the end of the tunnel.

[BlueDun]

On 12/14/2023 at 11:06 AM, EricJ said:

It sounds like the stop switch didn't engage, so the motor kept running after the gear was down.   That just jams the motor at the end of the gear travel so it popped the breaker.

The electric gear won't back-run and let the gear collapse, and it's likely that the gear is past what it needs to be overcenter and safe, especially since the floor indicator is indicating locked.    You *probably* didn't have much to fear by handling it on the ground, but it's best to not push your luck now that it's in your hangar.

It also sounds like probably all that's wrong is to fix the stop switch issue, which may not be too difficult, but I agree that you want some competent eyes to do that and check everything (preloads, etc.) along the way.   Some gear swings on jacks will be in order, for sure.

Checking the gear preload isn't too difficult, but shouldn't be done in its current state with the motor likely over-run past the normal stop point.   You'll want to get the stop switch fixed, then check the preloads and make sure everything is still where it needs to be.

Mooney gear is low maintenance with respect to the suspension (pucks rather than oleos) and the actuation system (electric motor or Johnson bar as opposed to electro-hydraulic or whatever), but rigging it properly, including the stop switch, is a little tedious and requires some attention to detail.  It's not really worse than most other airplanes, it's just one of the areas of Mooney maintenance where some experience can be very valuable.

 

On 12/23/2023 at 1:59 AM, 1980Mooney said:

Only one of the 2 MLG tubes is bent?  Everything is linked together. If it bent (buckled) because the Dukes actuator over- extended (due to lack of microswitch stop) then everything was overextended. Every tube should be checked for straightness. And turnbuckles for any 
 

On the other hand perhaps the one tube had some residual damage from the original gear up and it was the first to bend. 
 

check out this post

 

That's my bird, and it was down for 5 months as we sourced a new tube, re-rigged etc. The shop I used has done them before and knows Mooneys. Get a second opinion, find a way per Muncy to clamp gear, if possible and get it to the right shop. I am just catching up on thr thread before I go into detail in a post.

[N201MKTurbo]

I looks like that tube with the new paint was replaced at some time. It also looks like the clamp that holds the switch pusher flag got caught on the airframe and stopped the flag from pushing on the switch to stop the motor.

I have the exact same actuator, and have my belly open right now. I will get some pics today.

[N201MKTurbo]

You can test the switches by pulling the circuit breaker for the actuator then turning on the master and selecting gear down. you can move the gear by spinning the rubber coupler in the actuator with your thumb and forefinger. When you actuate the switch, you should hear the gear contactors clunk. You can also just push on the switch and hear the contactors.

Be careful so some helper doesn't push in the circuit breaker when doing this. that actuator is powerful enough to hurt you bad.

https://www.filmpreservation.org/preserved-films/screening-room/shake-hands-with-danger-1975

[BlueDun]

Sorry that I was right about bent push pull rods as I learned through the thread. You do have to be careful about potential gear collapse given the rigging problems. I was close to one. I have the following observations and suggestions based on my recent experience. It took a lot of work and time. Sorry. Ironically, my journey started almost exactly a year ago.

I am grateful for the advice I got from the folks here, Saavy, and M20Doc (Clarence). Hopefully this helps.

The shop had seen this once before on the exact same model, and they do not know what causes/caused it. If it were bad landings or side loads, they think they would have seen the problem much more often. We were close to landing and having the left gear collapse on us. This did happen to the other plane with the same problem. Our tip off was a strange sound on gear deployment caught at annual.

It can be caused by misadjusted spring tension at forward ends of rods, defective linit switch and bent paddles, and out of alignment rigging. The motor is rated way more force than needed and can easily bend landing gear actuating tubes.

It was really hard to find a good push pull tube. We got a new one from Mooney factory eventually. Some shops will NOT use a salvaged tube unless it is certified and passes certain tests. Some will only use an OEM tagged tube. Please *Confirm* before you take your plane to a shop what their requirements are if you cannot get a new rod and how one could by x-rayed and certified to their satisfaction. Or a tube that undergoes NDT to their specs. You do not want your plane stuck in a shop with no options. Do this even with the shop I recommend. They finished my plane in May and familiar with all the issues.

They may want to overhaul the actuator, but there are not kits or springs available as you all know, so you will have to navigate that issue. Get ahead of it. Lead time on new tubes if none are in stock is about 20 weeks. Sorry for the bad news. You can then expect 30 to 40 hours for rigging alone and 3 hours for tubes etc. I rolled all this work into an Annual.

I recommend choosing a shop that a) knows Mooney's and these parts, b) has a dedicated team that finds parts, and c) has done this before and recently. 

The best are those who have done this and done it recently. The same as you would want for a surgery.

With the help of Savvy, I took my plane to Chautaqua Aircraft Sales in Jamestown, NY. It is a Mooney Service Center. It was worth it for me and may be for you as well to take a long trip for this. Given the stakes, don't worry about where you are going. This will take months. @DonMuncy had the good idea of setting the gear for stability and transport. So, call the shop and I bet they can guide local MX on how to do it.

Chautaqua's owner Lou Nalbone was wonderful, as were Mike Johnson, who oversaw MX, and Carl Bjurlin. Dedicated parts people sourced0 down to the bolt. They were in touch directly with Frank Crawford, main tech rep at Mooney aircraft. They were meticulous and had an "ace rigger" who did a Mooney just before mine. 

https://chautaircraft.com/  (716) 664-7700

Happy to help and consult further, just as the rest of the Mooney Space community set me on the right path.

 

 

[EricJ]

27 minutes ago, N201MKTurbo said:

You can test the switches by pulling the circuit breaker for the actuator then turning on the master and selecting gear down. you can move the gear by spinning the rubber coupler in the actuator with your thumb and forefinger. When you actuate the switch, you should hear the gear contactors clunk. You can also just push on the switch and hear the contactors.

Be careful so some helper doesn't push in the circuit breaker when doing this. that actuator is powerful enough to hurt you bad.

https://www.filmpreservation.org/preserved-films/screening-room/shake-hands-with-danger-1975

I usually reference the Staplerfahrer Klaus video:

https://www.youtube.com/watch?v=ChOHnSL7ZCg

 

[Ragsf15e]

1 hour ago, N201MKTurbo said:

I looks like that tube with the new paint was replaced at some time. It also looks like the clamp that holds the switch pusher flag got caught on the airframe and stopped the flag from pushing on the switch to stop the motor.

I have the exact same actuator, and have my belly open right now. I will get some pics today.

I have the dukes as well… is it really one failed electrical switch away from bending the rods like that?  There’s no mechanical stop that would prevent damage or pop the circuit breaker?  Seems like more would end up bent?

[kortopates]

35 minutes ago, Ragsf15e said:

I have the dukes as well… is it really one failed electrical switch away from bending the rods like that?  There’s no mechanical stop that would prevent damage or pop the circuit breaker?  Seems like more would end up bent?

Indeed it happens a lot more than you'd think. But these tubes aren't that hard to source from the factory, same tubes are used by many models and I've been able to get them in 2-6 weeks. In fact I don't  think it actually took upto 6 weeks.