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Mooney has been sitting


sdflysurf

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1 minute ago, Marauder said:

 


Not under the belly pan, it is in full view on the left main.


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That's right, it's the Gear Up indicator switch that's under the belly. 

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6 minutes ago, Marauder said:

 


Not under the belly pan, it is in full view on the left main.


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Cool - that is exactly where I told the A&P to check in my message last night.  I'm hoping it is a stuck switch vs having to replace those pucks!

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25 minutes ago, Hank said:

There's a test in the Maintenance Manual describing when the pucks should be replaced. It's a clearance measurement above the pucks when first jacked off the ground. Has nothing to do with appearances but material properties of the rubber.

Fantastic!  I'll look it up.  We are jacking it up today and I'll pass that along.

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3 hours ago, Marauder said:

 

Your F won’t have the airspeed switch, it will have a squat switch on the left main. I believe there may have been a few Fs with airspeed switches. I’ll snap a picture of it when I head to the airport in a bit. That way you will know for sure.

 

The switch is probably not being activated because the donuts are not expanding.

 

 

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My F, serial number 6800XX, has an airspeed switch.  No squat switch.  Don't you just love how they changed the design in the middle of a production year.

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3 hours ago, sdflysurf said:

Thanks for your reply - That is exactly what I am researching/looking for - to see if there is some safety switch that might be stuck (ie gear feels pressure from being on the ground so it knows it is on the ground and wont allow it to go up accidentally, airspeed as you described, etc).

So are you saying that the M20F has an airspeed pressure switch and so when you do a gear up test when the airplane is on jacks you have to blow into the pitot?  standard procedure?

I don't know if its standard procedure but it works.  In my airplane I had the A/P install and override switch on a 337.  So I don't have to blow in the pitot tube anymore.  

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I don't know if its standard procedure but it works.  In my airplane I had the A/P install and override switch on a 337.  So I don't have to blow in the pitot tube anymore.  


It was/is available as a kit from Mooney. For those us who fly in really cold weather and with squat switches, the donuts don’t always expand fully and would prevent gear retraction.

52d7bedf25524be9d92df16f9c920f75.jpg


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The squat switch is known for not working under certain conditions... related to rubber properties...

1) Prolonged squatting... the rubber donuts compress under weight, time, and temperature... it actually flows very slowly outwardly....

2) incredibly cold temperatures... the rubber donuts don’t un-compress quickly enough when the weight is removed...

3) If you have an airspeed switch it is loacted near the ASI, attached to the Pitot system....(?) There are a few pics around here of what it looks like...

4) If you have a bypass switch... that is a bit more obvious on the instrument panel...

5) methods of generating enough air pressure in the bypass switch include attaching a small rubber hose to the Pitot tube... rolling up the attached hose enough to show the ASI needle moving. The airspeed required is typical of exceeding the stall speed of the wing...  DO Not blow compressed air into the pitot system... that is known to break the sensitive internal bits and pieces of the ASI...

Modern POHs have a fairly good amount of info related to the systems that are on board the plane from when it left the factory... try to get the most recent POH for the M20F... probably dated 1976 or so...  wiring diagrams and operational information continued to improve through the 70s and 80s....

Nice drawings and pics, Marauder!

Best regards,

-a-

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Speaking of manuals...

The Mooney factory is known to recently supply electronic copies of maintenance and parts manuals... some have been posted around here recently...

Or call the factory to see if they are still available... 

Best regards,

-a-

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THANK YOU ALL!  Blew in the pitot (gently) and gear came up!

The mechanic has been at all of the checklist items and AD's and we have an IA lined up to sign off on the ANNUAL when we are ready for him, so no ferry permit necessary!

No need for Pitot/static/transponder test until we get it back near us (outside of mode C veil where we are going next).

Now - I have figured everything out except for some lights and buttons that are not labeled - can anyone help me with these?1982734231_ScreenShot2018-05-19at8_32_13AM.thumb.png.68a5867fb41ea86dbaa95dc3744fe36c.png

Left to right - Above the airspeed indicator gear up and gear down, then above Attitude Indicator I think that is vacuum pressure low (because I saw it go off when I got to 1700 RPM) and I'm just taking a guess that the next one is vacuum pressure too high??  Then to the right of that I think that has to do with the 2 place intercom... knob on left for pilot volume, not sure what the switches do and then knob on right is passenger volume.  Guessing this is just a 2 place intercom because I haven't found jacks in the back (yet).

Then there is this:

 

IMG_7232.thumb.jpg.a8a6f6507a8b3073bc732efac15aac67.jpg

What the heck is that 1-6 settable dial for?  it has gears behind it that drive what looks to be a 6 relay kind of device.

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6 minutes ago, sdflysurf said:

 

Then there is this:

IMG_7232.thumb.jpg.a8a6f6507a8b3073bc732efac15aac67.jpg

What the heck is that 1-6 settable dial for?  it has gears behind it that drive what looks to be a 6 relay kind of device.

Some fan speed? Dimmer? Warp factor?

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Landing gear lights are push to test... twist for iris control of the brightness... be careful of twisting them closed... you won’t see the lights at all...

two identical knobs are light controls... cabin lights and instrument lights...

The knob numbered 1-6.... dynamic ride control? Or magnatraction...? (No idea...) get a better pic of what all the gearing is behind it.  See if there is a label on the device... part number and manufacturer name is helpful...

Best regards,

-a-

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4 minutes ago, carusoam said:

Landing gear lights are push to test... twist for iris control of the brightness... be careful of twisting them closed... you won’t see the lights at all...

two identical knobs are light controls... cabin lights and instrument lights...

The knob numbered 1-5.... dynamic ride control? Or magnatraction...? (No idea...)

Best regards,

-a-

Excellent thank you.  so you think the switches between the knobs are actually to turn those lights on as well?  I am not there to test, but I'll have the A&P check.

My next guess on the 1-6 dial is for me to select how much cabin noise I want - maybe some 20 year old noise cancellation experiment.  Or maybe a cruise control?

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Looks like someone upgraded the strobes.  There usually is not a strobe in the rear.  Probably Wheelen strobe package.   Might consider flight planning to just leave the gear down.   Might also want to get a can of contact cleaner and exercise the squat switch.    Looks like there is some sort of extra vent tube in the pilot footwell.

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50 minutes ago, Yetti said:

Looks like someone upgraded the strobes.  There usually is not a strobe in the rear.  Probably Wheelen strobe package.   Might consider flight planning to just leave the gear down.   Might also want to get a can of contact cleaner and exercise the squat switch.    Looks like there is some sort of extra vent tube in the pilot footwell.

Thank you!  not sure what the extra vent tube in the footwell is for either.  Looks like we don't have a squat switch - just airspeed safeguard - got the gear down!

 

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On some there is a same diameter tube that come off the top of the intake vent on the copilots side.   Usually used to cool radios.   Someone might have been being creative.   Check vents on both sides just forward of the door for mud dobbers next. It will help cabin airflow when you get them out.

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3 hours ago, sdflysurf said:

Excellent thank you.  so you think the switches between the knobs are actually to turn those lights on as well?  I am not there to test, but I'll have the A&P check.

The round knobs for the lights are combination On/Off and dimmers. Fully CCW is Off; spin it right and they come on Dim and get brighter as you turn. This should be in your Owners Manual. No idea what the little switches are in between . . .

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4 hours ago, sdflysurf said:

THANK YOU ALL!  Blew in the pitot (gently) and gear came up!

The mechanic has been at all of the checklist items and AD's and we have an IA lined up to sign off on the ANNUAL when we are ready for him, so no ferry permit necessary!

No need for Pitot/static/transponder test until we get it back near us (outside of mode C veil where we are going next).

Now - I have figured everything out except for some lights and buttons that are not labeled - can anyone help me with these?1982734231_ScreenShot2018-05-19at8_32_13AM.thumb.png.68a5867fb41ea86dbaa95dc3744fe36c.png

Left to right - Above the airspeed indicator gear up and gear down, then above Attitude Indicator I think that is vacuum pressure low (because I saw it go off when I got to 1700 RPM) and I'm just taking a guess that the next one is vacuum pressure too high??  Then to the right of that I think that has to do with the 2 place intercom... knob on left for pilot volume, not sure what the switches do and then knob on right is passenger volume.  Guessing this is just a 2 place intercom because I haven't found jacks in the back (yet).

Then there is this:

 

IMG_7232.thumb.jpg.a8a6f6507a8b3073bc732efac15aac67.jpg

What the heck is that 1-6 settable dial for?  it has gears behind it that drive what looks to be a 6 relay kind of device.

No need to ever blow into the pitot head to raise the gear.  A piece of surgical rubber tube slipped over the inlet, a piece of electrical tape to close the drain/vent on the bottom, roll the tube slowly to raise the pitot pressure, a clothes peg to trap the pressure, gear will raise and if the pitot doesn’t leak you have tested half of the system already.

Is the engine running?  Your mags are on both.

Clarence

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THANK YOU ALL!  Blew in the pitot (gently) and gear came up!
The mechanic has been at all of the checklist items and AD's and we have an IA lined up to sign off on the ANNUAL when we are ready for him, so no ferry permit necessary!
No need for Pitot/static/transponder test until we get it back near us (outside of mode C veil where we are going next).
Now - I have figured everything out except for some lights and buttons that are not labeled - can anyone help me with these?1982734231_ScreenShot2018-05-19at8_32_13AM.thumb.png.68a5867fb41ea86dbaa95dc3744fe36c.png
Left to right - Above the airspeed indicator gear up and gear down, then above Attitude Indicator I think that is vacuum pressure low (because I saw it go off when I got to 1700 RPM) and I'm just taking a guess that the next one is vacuum pressure too high??  Then to the right of that I think that has to do with the 2 place intercom... knob on left for pilot volume, not sure what the switches do and then knob on right is passenger volume.  Guessing this is just a 2 place intercom because I haven't found jacks in the back (yet).
Then there is this:
 
IMG_7232.thumb.jpg.a8a6f6507a8b3073bc732efac15aac67.jpg
What the heck is that 1-6 settable dial for?  it has gears behind it that drive what looks to be a 6 relay kind of device.


Can you post pictures of the whole panel? That 6 position switch might have been something to switch at probes on an early CHT/EGT monitor. Why 6? Probably because they couldn’t find a 4 position one.

A picture of the back of the switch might help.

Those micro switches could be for anything. Mine are used for autopilot power and a few other things. Looks like you need to do some detective work.

As for your blowing in the pitot. You did this while raising the gear? You would have needed to reach the minimum airspeed for the duration of the retraction. Did you look under the plane for a squat switch? You may still have a squat switch and the reason it is working now is the plane has been on jacks for a bit allowing the donuts to expand.

Here are my switches.

0d3a28ec9b7a230de6390362feb4a2d0.jpg


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13 hours ago, David Lloyd said:

That 6 position selector switch looks like one for the EGT.  

Sounds like the best explanation for that...it is right below the EGT instrument after all and I confirmed that there is an EGT Sensor on each cylinder's exhaust.

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13 hours ago, M20Doc said:

No need to ever blow into the pitot head to raise the gear.  A piece of surgical rubber tube slipped over the inlet, a piece of electrical tape to close the drain/vent on the bottom, roll the tube slowly to raise the pitot pressure, a clothes peg to trap the pressure, gear will raise and if the pitot doesn’t leak you have tested half of the system already.

Is the engine running?  Your mags are on both.

Clarence

Yes - this is a screen-grab from the video I took while doing run-up and instrument check.

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