fix my PC system and upgrade to auto pilot?

[bavareze]

Hello! 

I owned this mooney for 2+ years and the PC never worked.  I guess it is disconnected.  But it is there, I can see the boots in the wings and in the tail cone.

The mechanics I asked said don't worry about that, nobody knows how to fix it anymore and it won't do much for you anyways. 

After careful evaluation I realized that within the next 5-10 years I will likely not be in the position to upgrade to a different airplane so I think it makes sense to spend some money now and use that added feature for a good 5-10 years while I have this plane (1964 M20C).

What would be a cost to overhaul the PC system and who could do it in SoCal?

What about upgrading it to a heading bug or able to fly the plan from my GNS430W?  Would that be an option?  What about a budget?

I heard that installing a conventional auto pilot with electric servos will cost me more than $10k and that is out of the question, so I'm trying to see if there is any hope with this PC system.

 

Thanks!

 

[cliffy]

Brittian who supplied the PC system to Mooney is now out of business. Parts from wrecking yards "might" be available but one needs to know and understand the system itself. Manuals on it are available around the internet. 

Before you spend money on it (and yes I have one also) you  might look into TruTrak or Trio autopilots.  They are currently certifying them for Mooneys and may be available this summer. One is complete at around $7000 not counting install Considering that Brittain is now gone this is probably a better direction to consider. 

[Igor_U]

System is very simple and easy to understand if you have schematics and service manual. Problem is parts, now that Brittain is out of business but I was told they are still looking at providing some service in a future. We'll see. I've contacted them a month or so ago to buy spare rubber kits for servo and then was told all parts are in the warehouse after the liquidation of the company.

One issue you might have is non functioning gyro and that could be sent out for rebuild. Also you could have a simple leak in the tubing which is easy to replace.

You might want to contact LASAR to see if they have any parts for servos or other replacement parts. Cost of repairing PC system could be minimal and well worth it as system runs well, at leas in my plane.

 

 

Good luck.

[Yetti]

Do the simple things first.

Generally the tubing to the servos is the first thing to go.    From when Brittian did mine, the left side wing tubing goes first.    It is red and green vacuum tubing that you can get at the auto parts house.  It is just pulling wing panels to replace it.   Get a MitiMite vacuum puller and start with the servos to see if they are working.  There will be connections under the panel.

For heading bug and follow the GPS you will need an AccuTrac II    

[gearhead1450]

Yetti is right.  The PC system is great when operating properly.  The mechanics who told you it doesn't do much for you anyway were misinformed.  It would not be in the aircraft if it was not very useful.  I would not like to fly without it.  Though it is a relatively simple system you will have to find a good Mooney experienced mechanic with the proper manuals.  If your PC has not been operating or if it is just sluggish it is likely due to a vacuum leak.  It could be a problem in the control head but check for a vacuum leak from the control head out first.  Your mechanic should be able to isolate the problem area relatively easy.  If it is failed tubing in the wing, consider replacing at least all the tubing in the wing out to that servo.  If that is needed, hopefully, your mechanic has a skinny 15 year old with the mechanical skills to get the tubing removed and reinstalled on the servo and the servo out and back in if necessary.  I am not kidding, it is a near impossible task.  After fighting a few failures I just bit the bullet and replaced all the tubing in the entire system.  Fortunately I got tubing and compression nuts  (you will need new ones as the old ones can't be reused) from Brittain, but it has to be available elsewhere.  I do not have an alternate source.  It is a bummer that Brittain is out of business.  They were great folks to work with.

[carusoam]

Welcome aboard Gearhead!

So much knowledge about the PC system, where have you been? 

Best regards,

-a-

[carusoam]

Bavareze,

You are going to want to use the search function for this one.

There are several threads regarding the PC, Britain and challenges dozens of Mooneys have been through.

The PC system has worked well.  Without access to MooneySpace, many owners didn’t know how good the system can be.

Some problems are simple air leaks, followed by users disabling the system....

There is another current thread of an MSer asking PC questions...

You are not alone, on MS... 

Good luck,

-a-

[spectre6573]

I bought my m20c with the PC system not working. Luckily I sent all my servo's to them and got them Repair along with any of the other parts because I wanted the whole system good to go.

To give you advice on seeing if its even work it and hence since I just did the whole system and replaced all the tubing and the system is doing a fantastic job, check your your lines first. Its easy by just pulling the left avionics cover and you will see the vacuum manifold. on the left side you should see vacuum lines go to bulkhead fittings with the Red and Green tubing. Pull one of the vacuum tubes off and get a autozone brake bleeder and connect the hose to the pump and pull a vacuum. It may take a few pumps but watch the gauge on the pump and the ailerons and it should move and hold the vacuum. if it doesnt check the boots first for leaking then you will need to pull interior panels and check the lines. All my red lines were brittle and I change them out in less than 3 hours to both servos to the vacuum gauge.

 

The system work great and is very simple to maintain.

[Gary0747]

Where did you find new fittings for the tubing or did you reuse the old ones?

[carusoam]

They are standard barb fittings...

The old system used special springs on each barb.

Some people have used hose clamps to replace the springs.

Britain didn’t try to make it any more difficult than it needed to be.

 

PP thoughts only, not a mechanic...

Best regards,

-a-

 

[Yetti]

My Google Fu is strong this morning

 

 

 

 

[Yetti]

While we are here.   The filters on the Brittain system are Fram G12 with one of the inlets cut off.

[MyNameIsNobody]

Wish I would of had Jerry (RIP) yellow tag my TC100.  Add that to the things I wish I would have done pile.  He was a great human being and the heart and soul of Brittain.  CC and Kevin were awesome too.  Fingers crossed that someone steps in and like a Phoenix, Brittain rises again.

[Yetti]

You do know that the Yellow Tags mean absolutely nothing in the FAA World.   But I do have one for my TC100.

[Marauder]

18 minutes ago, Yetti said:

You do know that the Yellow Tags mean absolutely nothing in the FAA World.   But I do have one for my TC100.

What does mean something is if it has an 8130 attached to it.

[Yetti]

http://www.aviationpros.com/article/12008258/faa-feedback-the-yellow-tag

 

[MyNameIsNobody]

3 hours ago, Yetti said:

You do know that the Yellow Tags mean absolutely nothing in the FAA World.   But I do have one for my TC100.

Big guy being a little b me thinks.  Get over it man...

[MyNameIsNobody]

3 hours ago, Marauder said:

What does mean something is if it has an 8130 attached to it.

Exactly.

[MyNameIsNobody]

On 4/30/2018 at 3:06 AM, cliffy said:

Brittian who supplied the PC system to Mooney is now out of business. Parts from wrecking yards "might" be available but one needs to know and understand the system itself. Manuals on it are available around the internet. 

Before you spend money on it (and yes I have one also) you  might look into TruTrak or Trio autopilots.  They are currently certifying them for Mooneys and may be available this summer. One is complete at around $7000 not counting install Considering that Brittain is now gone this is probably a better direction to consider. 

Not to nit Cliffy, but he did say a $10k auto pilot is out of the question.  Your example is $7k PLUS install.  $10k...so this is a non-starter option.  A lot of folks benefited and more safer due to Brittain.  They were a cost effective option for lowly VFR guys like me.

[Yetti]

4 hours ago, Marauder said:

What does mean something is if it has an 8130 attached to it.

it means you paid more for it from Spruce.  A Yellow tag is not an 8130.

[bavareze]

On 4/30/2018 at 1:06 AM, cliffy said:

 

[bavareze]

I see this problem being split into 4 problems, to be solved:

 

- tubing

- servos

- gyro

- these 3 working together

 

tubing I assume is pretty standard hose so I guess I'll leave that at the end.

 

I do have the mooney service manual.  I'll go check the gyro.  Is that the rate of turn (DC unit) or the vacuum operated directional gyro?

 

What if the servos are leaking?  Is there a way to fix those without assistance from brittain?

 

Cheers!

[MyNameIsNobody]

52 minutes ago, Yetti said:

it means you paid more for it from Spruce.  A Yellow tag is not an 8130.

You are being a b Yetti.  You don’t buy a refurbed TC100 from Spruce...Maybe decades ago.  Jerry from Brittain...the company that manufactured it went through everything they refurbed to ensure proper function.  you received a yellow tag and logbook sticker with detailed information.  If he installed he flight tested and did weight and balance revision.  Go back and find a decade old photo of my bird on its belly and post it here if you can find it to get your rocks off...

[Yetti]

Put down the keyboard and slowly back away. 

[David Lloyd]

I had a '65 C with the PC inop when the plane was purchased.  Previous owner said the same.  I checked vacuum to the gyro, lines, servos, everything seemed good.  Eventually found the shuttle valve under the panel to be stuck. Disassembled, cleaned, a little light oil and all was good. Look at a schematic of the system and start checking, soon you will know more about your simple wing leveler than your mechanic.

I suspect the reason the spool in the piloted valve was stuck was the valve on the yoke was pulled out or held down with a film canister or rubber bands to continuously disable the PC. A small static vacuum is always on that line unless the button is pushed.  It then draws in a small flow of unfiltered air, dust, grease and cat hair to clog the piloted valve spool permanently disabling the PC.

Edited May 11, 2018 by David Lloyd