Oxygen bottle regulator overhaul - suggestions?

[Parker_Woodruff]

I've done a fair amount of troubleshooting for my leaking O2 bottle and it appears my regulator is leaking. Last night I was down to about 1250 PSI from 1600 or 1700 PSI that was there on Friday. I guess I'll be slogging along to Texas and back on Friday at non-O2 altitudes.

I haven't had to do this before and I hear it's quite expensive. Does anyone have any shop recommendations?

Other than this nagging problem, I'm happy to say my plane is squawk free.

[jlunseth]

I mentioned this over on the "Red Board," but the shut off valve mechanism can be a problem. If you haven't looked hard at that, I would check it. Maybe do a soap test on the valve and the line in that vicinity?

[Parker_Woodruff]

I mentioned this over on the "Red Board," but the shut off valve mechanism can be a problem. If you haven't looked hard at that, I would check it. Maybe do a soap test on the valve and the line in that vicinity?

Nuthin. Tried it 3 times. I went out to the airport and it's sitting at the same PSI it was yesterday at 2pm. 1250. I'm trying to figure out if with the temp and pressure changes between the bottles it could have settled out at 300 PSI difference.

[FBCK]

Nuthin. Tried it 3 times. I went out to the airport and it's sitting at the same PSI it was yesterday at 2pm. 1250. I'm trying to figure out if with the temp and pressure changes between the bottles it could have settled out at 300 PSI difference.

I had my regulator rebuilt earlier this year, total bill was $700 or so, likely similiar to yours, done in Canada however, so likely cheaper down where you are.

[jlunseth]

If the difference is 300 psi, the answer is absolutely yes, OAT can make that much of a difference without a leak. My system does not leak, and living in a climate with temperature changes from one day to the next, that kind of variation is not out of the ordinary. Generally, they fill it to 1800 psi. If they do that on a cold day and the next time I am out it is hot and the plane has sat in the sun, I have often seen 2100. Or vice versa going from hot one day to cold the next. Leave it for a couple of weeks. If you come back and it is 500 or less, then you have a problem. But right now I would question whether it is a problem.

We see this all the time with scuba tanks also. I would not expect a variation over about 200 psi with those, but then they generally don't sit in the hot sun because we try not to do that, and I have seen larger variations where scuba tanks have sat in the sun.

Incidentally, you may know this, but you should consider 500 psi a minimum. The reason is that there needs to be positive pressure in the bottle to keep the bottle from "inhaling" ambient air. If it does that, it can take in moist air, which results in condensation in the tank, which results in moisture damage from the inside out. I would not get too excited about this limit, if you are on a long trip and need to breath it down to 300 for example, you still have positive pressure in the tank. But I would get it filled right away, before a cold day comes along and that 300 psi shrinks to next to nothing.

[thinwing]

I think a 300 lb drop is too high.There are temp/filling pres tables that the line guys use to compensate for a "hot" fill.Say tank is normally rated for 1850 lbs at 15 celsius...so at 30 celsius a full tank would be 1975 or so....I am more suspicious of the bowdon cable actuating the turn off lever on the regulator...if that is slightly out of rig and you exercised the on/off 2 0r 3 times and press than held at 1250..it means you finally got the lever to the closed position...I doubt your temps are varying that much...I donot notice that great a pressure change from say 90 on the ground and minus 37 at altitude...k

[fantom]

I guess I'll be slogging along to Texas and back on Friday at non-O2 altitudes.

I'm happy to say my plane is squawk free.

Happy you're almost squawk free, and hope you realize some of us non turbo guys might take offense at your slogging remark.

A good dive shop will be expert in checking your, if necessary, repairing your regulator.

[Parker_Woodruff]

Happy you're almost squawk free, and hope you realize some of us non turbo guys might take offense at your slogging remark.

You get depressed when you see the 30-40 knot tailwind likely for this weekend up around 17,000 ft... 220 knot average groundspeed would give me sub-4 hours from Austin to Lakeland, even going via Tallahassee (TLH) and not risking the over-water crossing. EDC - TLH - LAL

[jlunseth]

My personal best was a tailwind of 105-110 kts. a couple of weeks ago, which gave me 275 GS for part of a trip from Peoria to Fredrick, MD. Likety split. http://flightaware.com/live/flight/N381SP/history/20120922/1200Z/KPIA/KFDK/tracklog

They gave me a turbine Arrival (twolf.twolf2) coming in to Minneapolis this weekend, don't know why, must have been the altitude (FL210) not the speed, which was only around 160 kts. with a slight headwind. Unfortunately I only got to do part of the Arrival, they "outted" me after a couple of waypoints. I got "say type aircraft" and when I told them I was a turbo piston they broke me off the Arrival and put me direct to the airport instead, which was fine with me, but it would have been fun.

[fantom]

You get depressed when you see the 30-40 knot tailwind likely for this weekend up around 17,000 ft... 220 knot average groundspeed would give me sub-4 hours from Austin to Lakeland, even going via Tallahassee (TLH) and not risking the over-water crossing. EDC - TLH - LAL

Great....now I'm offended and depressed

[N601RX]

Nuthin. Tried it 3 times. I went out to the airport and it's sitting at the same PSI it was yesterday at 2pm. 1250. I'm trying to figure out if with the temp and pressure changes between the bottles it could have settled out at 300 PSI difference.

P1/T1=P2/T2 Temp is in Kelvin

[Awful_Charlie]

The Bravo POH has pressures ranging from 1650 to 2050 PSI for the filling pressure, temperatures from 0F to 90F (Section VII, table 7-12), what was the temperature when you noticed it high and low? A couple of hours in the flight levels will cool it off considerably.

Unfortunately I don't have a problem with air getting into my tyres when they go a bit soft at 30PSI, and as at 600PSI there is still 2 man hours at FL180 left, before you get into Oxysavers, I don't mind getting down to a few hundred PS, it is more about if it will fit the trips planned.

[DonMuncy]

Parker,

Until you see soap bubbles from the regulator, I would not assume that is the problem. For a long perioe of time, my 231 would lose pressure like that. I then took the access panel off and manually closed the regulator valve. The loss of pressure stopped until I used it again. The "cable" was not shutting off the valve. It is understandable, as that cable looks like the throttle wire from a lawnmower. It is no real trick to get a larger diameter cable and replace the original. Mine now holds pressure well. If you want specifics about the new cable, let me know.

[carusoam]

I like Mooney pilots...

Anyone that can cite the ideal gas law and stay within the forum topic without being named Boyle has got to be good.

Best regards,

-a-

[Parker_Woodruff]

Mine now holds pressure well. If you want specifics about the new cable, let me know.

Tried sending you a PM but it said you couldn't receive any more. Might give you a call in the next day or 2.

[DonMuncy]

Parker,

I apparently don't know how to access my PMs. If you or someone else could point the way, maybe I can get in and look. I will continue to try to find them. I bothers me that others may have PMed me as well. If they have and I haven't answered, feel free to call me 214 207-6744 or straight e-mail, d.muncy@sbcglobal.net

[DonMuncy]

Parker,

I finally found my way into my PMs. I did not know that I was supposed to be deleting my Pms, so my box was full. I deleted all of them, so I should be able to get them again. Anyway, call, e-mail, PM or any other way is fine.