Removal of GPS/COM

[Patto]

New to the forums here and also a new Mooney M20C owner!

Unfortunately, one thing that was not caught during the inspection was that the KX155 was not receiving comm transmissions very well.  The previous owner recently had it serviced for the same issue, so I'd like to remove the unit and send it back to the company that worked on it before.

Do any of you have a YouTube video or maybe just some simple instructions on how to remove it?  I can see how to unplug it in the back, just not certain how to pull the unit out.

Thanks in advance.

[DXB]

Congrats on the new bird! Cs are great.  Consider posting some pix.  Unlike me, the people here who actually know stuff will address your question shortly...

[N601RX]

Don't remove anything on the back. Turn the recessed Allen head screw on the front counter clock wise and it will push it out 

[Andy95W]

FWIW, if it's a recurring problem, it's probably not the radio, it's probably the antenna or antenna connection, or surface corrosion between the antenna and skin.  Good luck.

[Patto]

Thank you for the advice folks.  Yes, I thought about the issue being the antenna rather than the unit, but according to the paperwork from when it was serviced, they said they repaired and tested it and found it to be working properly when they were done.  I guess it could be the antenna and they did not do a thorough test.

[Andy95W]

That sounds like the statement from the 8130 Airworthiness sheet.  The radio shop will remove the unit and check it on their bench.  Unless they actually say that they inspected and checked the antenna and its connections, and then checked transmission and reception strength, I'm still suspicious.  

[carqwik]

My KX 165 has visited at least three avionics shop....the nav is off by 15 degrees on the HSI.  Each time they check it, "tune it," and release it to me...and it works ok for about maybe a flight or two before drifting off again until it hits that 15 degree error.  So just cause an avionics shop signs off on something, doesn't mean your troubles disappear. 

BTW, anyone have a clue as to my KX-165 nav problem??

[Guest]

5 hours ago, Patto said:

New to the forums here and also a new Mooney M20C owner!

Unfortunately, one thing that was not caught during the inspection was that the KX155 was not receiving comm transmissions very well.  The previous owner recently had it serviced for the same issue, so I'd like to remove the unit and send it back to the company that worked on it before.

Do any of you have a YouTube video or maybe just some simple instructions on how to remove it?  I can see how to unplug it in the back, just not certain how to pull the unit out.

Thanks in advance.

With a 3/32" Allen wrench you can remove most major brands of avionics.  If you have a friend with the same radio try switching before sending it to a radio shop.

Clarence

[carusoam]

Good time to clean the row of contacts with the proper electronic contact cleaner whilst the radio is out...

I am only a PP, not an electronics guy.

Best regards,

-a-

[Pictreed]

17 hours ago, M20Doc said:

With a 3/32" Allen wrench you can remove most major brands of avionics.  If you have a friend with the same radio try switching before sending it to a radio shop.

Clarence

Welcome to Mooney ownership. 

Yes that's the way to remove it.  There's a small hole on the bottom of the faceplate.  Stick the long Allen wrench in there and unscrew.  As you unscrew it grab the face plate and pull it towards you.

I had the same problems.  When I sent it in they said the capacitors leaked and ruined several boards so it was unrepairable.

I used a friends to fly my plane to the avionics shop to get it replaced.

Instead of buying another 155 that could go out I got a new Garmin.  

Good luck.

Tim

[N201MKTurbo]

When I was just getting started in the electronics repair business an old timer told me that the best thing to clean the contacts of gold plated card edge connectors was a one dollar bill. I have found his advice to be good. Just fold part of the bill over the contacts and rub it until the contacts get shiny.

[Guest]

1 hour ago, Pictreed said:

Welcome to Mooney ownership. 

Yes that's the way to remove it.  There's a small hole on the bottom of the faceplate.  Stick the long Allen wrench in there and unscrew.  As you unscrew it grab the face plate and pull it towards you.

I had the same problems.  When I sent it in they said the capacitors leaked and ruined several boards so it was unrepairable.

I used a friends to fly my plane to the avionics shop to get it replaced.

Instead of buying another 155 that could go out I got a new Garmin.  

Good luck.

Tim

Thanks so much,

I don't own a Mooney anymore, I own a brand P and the eastern Canada MSC.

Clarence

[Patto]

So much good advice in just one day.  Thank you all for your help.

My other old-school Nav/Com works just fine.  Do they likely share the same antenna, and if so, which one is it on the exterior of the aircraft?  My apologies for the newbie questions and my gratitude for all of the assistance.

 

 

 

[N601RX]

They will each have their own antenna. It will be a vertical antenna about 15 inches long

[Patto]

So loosened the screw while pulling out on it but it won't budge. I can feel it get loose in the panel, but it feels anchored in the back. What am I doing wrong?

 

Oh, and it's the KLX135A that I'm removing, not the 155.

[1524J]

You need to continue to turn the screw counter clockwise until it stops. There's a lever at the back of the radio that needs to be in the proper position to release. The screw will actually "push" the radio out (and pull the radio in when installing). Pull (or push) just enough to help the screw do it's job. It'll slide out easily when done.

[steingar]

And the Allen wrench thingie isn't exactly standard issue either, but your mechanic should have one. Nothing specific to this about Mooneys, welcome to airplane ownership.

sent my kn135A for repair multiple times without any real fix.  But like the guys said check the cable that runs from the box to the antenna, as well as the antenna itself.  These things are complicated.

[Patto]

Well, it came out some of the way after just muscling through a couple spots where the screw seemed to get stuck, then it would get easy again, and now it is just free-wheeling but the unit will not pull out.  I'm afraid the screw is either stripped out in the head or broken.  Either way, I can't get the unit to pull out.  What should I do now?

 

[ArtVandelay]

I would call an expert, my guess is they will pull off the glareshield and/or surrounding avionics to get access.

[takair]

You often have to "jiggle" (official technical term) the radio left and right as you turn the cam screw rather than relying purely on the screw/cam to push it out.  Try turning the screw back in so it recaptures and then doing the jiggle thing.  They often get wedged in the stack up. If the radio above and below come out, it may help with this and you may see if the cam is engaged or not.  It is quite easy once you have the feel.  If the screw is spinning, you may have stripped something.  

I agree with the others, this may not be simply the radio.  Can you provide other symptoms?  There are threads with some Q and A on radios.  The more info you provide to the shop (or us) the cheaper it will be to repair.  Otherwise the shop is just guessing.  Range and noise issues are very difficult to diagnose on a static aircraft. 

ref the KX 165 Nav issue, it depends on the CDI too.  It could very well be a CDI resolver issue.  In these cases you would ideally provide both to the shop so they can bench check and calibrate together.  Some of the older units are difficult to get parts for.

[takair]

As a side note, from the photo, there should be enough room to see the cam at the center bottom of the radio.  Looks like it may have gotten wedged outside of its slot.

[Bob_Belville]

Maybe pull the NAVCOM above the radio that has you stumped. Doing that will give you a feel for how the seating system works. Pull it out, study the keep, run it in and out. (Be sure the Allen is all the way CCW when you reinsert the radio.)

You report the screw is "free wheeling". That's not where you want it to be. I'd push it in and tighten the radio all the way clockwise. Then start over and be sure the Allen goes all the way to its stop. In that position the lever should not interfere with removal. 

It is likely something is catching a little on one of the 4 sides but you should not have to force it, as suggested it takes a little wiggling, twisting to free it. If you've turned the Allen wrench all the way counterclockwise to its stop the radio should be loose in the rack. push in/pull out firmly. If it's hanging on something you'll want to try pulling while holding it to the left, right, top, bottom to get past whatever it's catching on. 

Got a friend or mechanic there who has done this before? Let them try it - they'll show you how to hold your tongue right. 

[Guest]

19 hours ago, Patto said:

Well, it came out some of the way after just muscling through a couple spots where the screw seemed to get stuck, then it would get easy again, and now it is just free-wheeling but the unit will not pull out.  I'm afraid the screw is either stripped out in the head or broken.  Either way, I can't get the unit to pull out.  What should I do now?

 

Over turning the release screw can break the lock, knowing when to stop is the key.  I'd suggest removing the KLX135 to access the bottom of the 155, but if you've broken the 155 you may just want to fly to the avionics shop and let them deal with it.

Clarence

[Patto]

On 7/13/2016 at 5:55 PM, M20Doc said:

Over turning the release screw can break the lock, knowing when to stop is the key.  I'd suggest removing the KLX135 to access the bottom of the 155, but if you've broken the 155 you may just want to fly to the avionics shop and let them deal with it.

Clarence

It's the KLX135 that I am trying to remove (I previously said the 155, which was wrong).  I pulled and pulled, but the deck never actually came loose, so something was wrong to begin with.  I imagine that I will have to take it to an avionics shop and pay them to remove it.  It's under warranty from work that was done in March, but that outfit is in California and I'm in Oregon.  Would be a fun excuse for a cross-country trip to just fly it down there though...

[Patto]

On 7/13/2016 at 6:00 AM, Bob_Belville said:

Maybe pull the NAVCOM above the radio that has you stumped. Doing that will give you a feel for how the seating system works. Pull it out, study the keep, run it in and out. (Be sure the Allen is all the way CCW when you reinsert the radio.)

You report the screw is "free wheeling". That's not where you want it to be. I'd push it in and tighten the radio all the way clockwise. Then start over and be sure the Allen goes all the way to its stop. In that position the lever should not interfere with removal. 

It is likely something is catching a little on one of the 4 sides but you should not have to force it, as suggested it takes a little wiggling, twisting to free it. If you've turned the Allen wrench all the way counterclockwise to its stop the radio should be loose in the rack. push in/pull out firmly. If it's hanging on something you'll want to try pulling while holding it to the left, right, top, bottom to get past whatever it's catching on. 

Got a friend or mechanic there who has done this before? Let them try it - they'll show you how to hold your tongue right. 

The screw was very difficult to turn at multiple times but never actually let the unit break free.  I can't get it to push back in and catch, so either the screw is broken or it is stuck and the head is stripped out.  It's difficult to tell.  I may try a new allen key and see if that helps.  The one I have looks like it took some damage trying to turn the screw.  I'm wondering if there was some rust in there or if someone used loctite to install it, thinking it might wiggle loose.