Oxygen fill port

[Stnelson903]

I have a 1979 M20k 231. Serial #8. It has O2. The system is apparently simpler than newer models. There is not a control in the cockpit to turn the system on. The gauge is in the hat rack. The filler fitting is inside the tail.

The filler fitting looks exactly like the ones in twin cessnas. It has an internal check valve in it and is mounted.

Anybody know the manufacturer and model of this fitting? I either need a overhaul kit or another fitting.

[N201MKTurbo]

34 minutes ago, Stnelson903 said:

 

I have a 1979 M20k 231. Serial #8. It has O2. The system is apparently simpler than newer models. There is not a control in the cockpit to turn the system on. The gauge is in the hat rack. The filler fitting is inside the tail.

The filler fitting looks exactly like the ones in twin cessnas. It has an internal check valve in it and is mounted.

Anybody know the manufacturer and model of this fitting? I either need a overhaul kit or another fitting.

 

Do you have a picture?

[LANCECASPER]

2 hours ago, Stnelson903 said:

 

I have a 1979 M20k 231. Serial #8. It has O2. The system is apparently simpler than newer models. There is not a control in the cockpit to turn the system on. The gauge is in the hat rack. The filler fitting is inside the tail.

The filler fitting looks exactly like the ones in twin cessnas. It has an internal check valve in it and is mounted.

Anybody know the manufacturer and model of this fitting? I either need a overhaul kit or another fitting.

 

Sounds like an aftermarket system. I had a later 231 (1983 model) and it was exactly like later 252’s,TLS, etc.

[kortopates]

Like Lance says above, it doesn't sounds like the Mooney OEM system, in fact with the gauge in the hat rack where it can't be read really sounds like a hangar fairy system. Makes me wonder if you'll find any paper work for approval given the setup?

If they used the same O2 port used by Mooney it will be a Scott port fitting, same for the outlets in the cabin which may not be OEM either. The O2 ports use a high pressure needle valve - which is probably what is leaking. If I was in your position, not being sure what you have, I'd pull the port and send it to these folks for repair. https://www.c-l-aero.com/ They are a repair station for O2 systems. Its a very inexpensive repair and Jeff will return it to you very quickly. 

But if you're serious about flying high with that, I'd run the 1/8 copper line for the gauge and cable up to the pilot sidewall for a proper install so you'll be able to monitor your O2 supply. Imagine how the accident report would read if you ran out of O2 up high and became hypoxic or worse. There is a bracket you'll need by the regulator and a little hardware at the sidewall but I doubt the parts will add up to that much. All of these parts are in your IPC. 

[Stnelson903]

Like Lance says above, it doesn't sounds like the Mooney OEM system, in fact with the gauge in the hat rack where it can't be read really sounds like a hangar fairy system. Makes me wonder if you'll find any paper work for approval given the setup?
If they used the same O2 port used by Mooney it will be a Scott port fitting, same for the outlets in the cabin which may not be OEM either. The O2 ports use a high pressure needle valve - which is probably what is leaking. If I was in your position, not being sure what you have, I'd pull the port and send it to these folks for repair. https://www.c-l-aero.com/ They are a repair station for O2 systems. Its a very inexpensive repair and Jeff will return it to you very quickly. 
But if you're serious about flying high with that, I'd run the 1/8 copper line for the gauge and cable up to the pilot sidewall for a proper install so you'll be able to monitor your O2 supply. Imagine how the accident report would read if you ran out of O2 up high and became hypoxic or worse. There is a bracket you'll need by the regulator and a little hardware at the sidewall but I doubt the parts will add up to that much. All of these parts are in your IPC. 

Mine has everything you have mentioned, except the shutoff in the front. Many of the cessnas have the O2 gauge on the back wall, all you do is look over your shoulder. The leak is at the filler port, I found it.
I’ll look at Scott for a oring kit.


S. T. Nelson
N231JG
Just Go

[gsxrpilot]

Yep sounds like some hangar fairies retrofitted a cessna rig into a 231.

[Stnelson903]

Yep sounds like some hangar fairies retrofitted a cessna rig into a 231.

I’ll definitely check through the books


S. T. Nelson
N231JG
Just Go

[Stnelson903]

Plane was factory flown and accepted in dec of 78. Second entry was installing o2 system with 337 in California 5 days after factory test flight


S. T. Nelson
N231JG
Just Go

[kortopates]

Out of curiosity I checked the FARs and was surprised that part 23 only requires an outlet for every person, but the requirement for a pilot O2 gauge and control doesn't begin till Part 25 for Transport aircraft.
However, the last sentence leaves it in a gray area ripe for difference in FSDO opinion.
Part 23.2320
(e) If an oxygen system is installed in the airplane, it must—

(1) Effectively provide oxygen to each user to prevent the effects of hypoxia; and

(2) Be free from hazards in itself, in its method of operation, and its effect upon other components.

But we know it's not possible to read a gauge in the back of the hat rack while piloting. I sure can't bend my neck anywhere near that far; especially while buckled into the front seat.

I keep some small emergency backup O2 cylinders in the seat pocket for flying in the flight levels using the system below.
Seems especially appropriate for a system that you can't monitor the supply in flight.
http://www.mhoxygen.com/portable-constant-flow/emergency-systems




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[DanM20C]

My 79 K had an aftermarket system installed in 1979.  It sounds similar to the OP's.  No on/off from the cockpit and the gauge is mounted above the hat rack as well as the fill port.  I have seen a lot of 231's with a similar system.

I have a 337 that claims it was a "RayJay Corp Sky Ox System Model SK 101-4X-78".  The 337 references a Flight Manual Supplement that is no longer in my flight manual.  Maybe @tomgo2 has some info? 

My tank and regulator were removed long ago.  I carry two 24 cubic ft portables when traveling alone or with one other person.  My kids are little (5 and 4 y/o) so I leave the O2 behind and fly low when we are traveling as a family.

I thought hard about bringing my system back on line but it would costs several AMU's just to get another bottle and regulator.  Then I would be left with a system with no on/off valve and a miniature gauge as far away from me as possible.  After the kids are older and a long list of other upgrades get accomplished I might revisit my onboard o2.

Cheers,

Dan

[tomgo2]

Hi Dan, yes. RAJAY was the original developer of the Sky Ox STCs. I ran across a bunch of data the other day on it. I'll take another look and see what I can find out for you.

[Stnelson903]

Thanks for the input y’all. It seems to be quite simple and easy the see and read the gauge on the back wall.
I think it is what, 6’ away.


S. T. Nelson
N231JG
Just Go