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pnicholson
Joined: 04 Jun 2011
Posts: 46
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 Posted: Mon Oct 27, 2014 10:21 am Post subject: loss of main air |
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Hello,
    I have replaced my main air valve and flap handle valve recently. No issues immediately thereafter. Air system behaved normally.
A month later, and three flights in a row, I have not been able to generate over 30 bars. It just stays there. When I land, I bleed off an additional five with flaps and brakes etc. With the engine off and Main air open, I use an external tank to fill to 50 bars. I hear no hissing whatsoever. Also of note, my snot valve after landing has little to no pressure. Goo just slowly drips/oozes out.
Any thoughts on where to start?
Thanks,
Phil Nicholson
CJ6A - C-FEPN
pednicholson(at)gmail.com (pednicholson(at)gmail.com)
[quote][b]
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dougsappllc(at)gmail.com
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| Posted: Mon Oct 27, 2014 10:30 am Post subject: loss of main air |
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Phil,Check:
- Remove the needle valve from your snot valve, it is probably rusty and your pump cannot keep up with the leak.
- If not the above check the alu crush washers on the banjo fitting on the compressor. Â we have a kit for that..........
- Check the line going from the compressor to the snot valve for cracks.
Give me a call if I can help, but my money is on #1.
Doug
On Mon, Oct 27, 2014 at 11:19 AM, Philip Nicholson <pednicholson(at)gmail.com (pednicholson(at)gmail.com)> wrote:
[quote]Hello,
    I have replaced my main air valve and flap handle valve recently. No issues immediately thereafter. Air system behaved normally.
A month later, and three flights in a row, I have not been able to generate over 30 bars. It just stays there. When I land, I bleed off an additional five with flaps and brakes etc. With the engine off and Main air open, I use an external tank to fill to 50 bars. I hear no hissing whatsoever. Also of note, my snot valve after landing has little to no pressure. Goo just slowly drips/oozes out.
Any thoughts on where to start?
Thanks,
Phil Nicholson
CJ6A - C-FEPN
pednicholson(at)gmail.com (pednicholson(at)gmail.com)
| Quote: |
et="_blank">http://www.matronics.com/Navigator?Yak-List
tp://forums.matronics.com
_blank">http://www.matronics.com/contribution
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[b]
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KingCJ6(at)aol.com
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| Posted: Mon Oct 27, 2014 10:32 am Post subject: loss of main air |
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Check the spring on your snot valve , make sure it is holding the valve fully closed.
Dave
In a message dated 10/27/2014 11:21:26 A.M. Pacific Daylight Time, pednicholson(at)gmail.com writes:
| Quote: | Hello,
I have replaced my main air valve and flap handle valve recently. No issues immediately thereafter. Air system behaved normally.
A month later, and three flights in a row, I have not been able to generate over 30 bars. It just stays there. When I land, I bleed off an additional five with flaps and brakes etc. With the engine off and Main air open, I use an external tank to fill to 50 bars. I hear no hissing whatsoever. Also of note, my snot valve after landing has little to no pressure. Goo just slowly drips/oozes out.
Any thoughts on where to start?
Thanks,
Phil Nicholson
CJ6A - C-FEPN
pednicholson(at)gmail.com (pednicholson(at)gmail.com)
|
[quote][b]
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rocknpilot(at)hotmail.com
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| Posted: Mon Oct 27, 2014 10:36 am Post subject: loss of main air |
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Phil,
You are going to receive a plethora of responses to this question, but...just out of curiosity, have you checked the condition of your in-line air filter? Are you confident your compressor is producing air? The massive leak w/ no audible hiss is one thing, but stagnant pressure gauge / minimal release from the snot pot would seem to indicate the possibility that little to no air is 1) being generated, or 2) is not allowed to pass to the bottle due to a blockage.
Just my $.02. GOOD LUCK as I have spent oodles of hours on this exact issue. Please feel free to contact me directly, or on-list any time!
Rico Jaeger
915 S. 11th Ave.
Wausau, WI. 54401
715.529.7426
//
1966 Cessna 150F ^/---//-X
N8558G //Hangar #35 / AUW
//
1992 Yakovlev Yak 52 ^/---//-X
N21YK //
Hangar #21 / AUW
Date: Mon, 27 Oct 2014 14:19:31 -0400
Subject: loss of main air
From: pednicholson(at)gmail.com
To: Yak-List(at)matronics.com
Hello,
I have replaced my main air valve and flap handle valve recently. No issues immediately thereafter. Air system behaved normally.
A month later, and three flights in a row, I have not been able to generate over 30 bars. It just stays there. When I land, I bleed off an additional five with flaps and brakes etc. With the engine off and Main air open, I use an external tank to fill to 50 bars. I hear no hissing whatsoever. Also of note, my snot valve after landing has little to no pressure. Goo just slowly drips/oozes out.
Any thoughts on where to start?
Thanks,
Phil Nicholson
CJ6A - C-FEPN
pednicholson(at)gmail.com (pednicholson(at)gmail.com)
[quote]
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Ernie
Joined: 11 Jan 2006
Posts: 513
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| Posted: Mon Oct 27, 2014 11:09 am Post subject: loss of main air |
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I would start with your snot valve. It may be leaking. I found that the snot valve in the belly can also leak, and not allow the system to build pressure. I had the problem and could not hear any leaking.
If that doesn't do it then its a slow process of elimination. Attach a scuba bottle, with the main air valve closed, and make sure you can hear the pop off valve fart at the desired pressure, mine is set at 40 bar since I don't like pushing my air bottles. Then it's a matter of soapy water on all the joints, and look for the leak.
On Mon, Oct 27, 2014 at 2:19 PM, Philip Nicholson <pednicholson(at)gmail.com (pednicholson(at)gmail.com)> wrote:
[quote]Hello,
    I have replaced my main air valve and flap handle valve recently. No issues immediately thereafter. Air system behaved normally.
A month later, and three flights in a row, I have not been able to generate over 30 bars. It just stays there. When I land, I bleed off an additional five with flaps and brakes etc. With the engine off and Main air open, I use an external tank to fill to 50 bars. I hear no hissing whatsoever. Also of note, my snot valve after landing has little to no pressure. Goo just slowly drips/oozes out.
Any thoughts on where to start?
Thanks,
Phil Nicholson
CJ6A - C-FEPN
pednicholson(at)gmail.com (pednicholson(at)gmail.com)
| Quote: |
et="_blank">http://www.matronics.com/Navigator?Yak-List
tp://forums.matronics.com
_blank">http://www.matronics.com/contribution
|
[b]
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N13472(at)aol.com
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| Posted: Mon Oct 27, 2014 11:30 am Post subject: loss of main air |
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I would also remove and clean the output check valve on the compressor.
Tom Elliott
CJ-6A NX63727
777 Quartz Ave
PMB 7004
Sandy Valley NV
89019
Cell 541-297-5497
N13472(at)AOL.COM
From: owner-yak-list-server(at)matronics.com [mailto:owner-yak-list-server(at)matronics.com] On Behalf Of doug sapp
Sent: Monday, October 27, 2014 11:30 AM
To: yak-list(at)matronics.com
Subject: Re: loss of main air
Phil,
Check:
- Remove the needle valve from your snot valve, it is probably rusty and your pump cannot keep up with the leak.
- If not the above check the alu crush washers on the banjo fitting on the compressor. we have a kit for that..........
- Check the line going from the compressor to the snot valve for cracks.
Give me a call if I can help, but my money is on #1.
Doug
On Mon, Oct 27, 2014 at 11:19 AM, Philip Nicholson <pednicholson(at)gmail.com (pednicholson(at)gmail.com)> wrote:
Hello,
I have replaced my main air valve and flap handle valve recently. No issues immediately thereafter. Air system behaved normally.
A month later, and three flights in a row, I have not been able to generate over 30 bars. It just stays there. When I land, I bleed off an additional five with flaps and brakes etc. With the engine off and Main air open, I use an external tank to fill to 50 bars. I hear no hissing whatsoever. Also of note, my snot valve after landing has little to no pressure. Goo just slowly drips/oozes out.
Any thoughts on where to start?
Thanks,
Phil Nicholson
CJ6A - C-FEPN
pednicholson(at)gmail.com (pednicholson(at)gmail.com)
01234567890123
No virus found in this message.
Checked by AVG - www.avg.com
Version: 2015.0.5315 / 10/27/14
[quote][b]
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Dawg
Joined: 19 May 2013
Posts: 355
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| Posted: Mon Oct 27, 2014 4:46 pm Post subject: loss of main air |
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snot valve not seating properly.
On Oct 28, 2014, at 3:19 AM, Philip Nicholson <pednicholson(at)gmail.com (pednicholson(at)gmail.com)> wrote:
[quote]Hello,
I have replaced my main air valve and flap handle valve recently. No issues immediately thereafter. Air system behaved normally.
A month later, and three flights in a row, I have not been able to generate over 30 bars. It just stays there. When I land, I bleed off an additional five with flaps and brakes etc. With the engine off and Main air open, I use an external tank to fill to 50 bars. I hear no hissing whatsoever. Also of note, my snot valve after landing has little to no pressure. Goo just slowly drips/oozes out.
Any thoughts on where to start?
Thanks,
Phil Nicholson
CJ6A - C-FEPN
pednicholson(at)gmail.com (pednicholson(at)gmail.com)
| Quote: |
href="http://www.matronics.com/Navigator?Yak-List">http://www.matronics.com/Navigator?Yak-List
href="http://forums.matronics.com/">http://forums.matronics.com
href="http://www.matronics.com/contribution">http://www.matronics.com/contribution
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[b]
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mikeholoman(at)hotmail.co
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| Posted: Mon Oct 27, 2014 6:43 pm Post subject: loss of main air |
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If You are losing air from the compressor to the snot valve, you need to look for a leak starting at the banjo fitting, flare fittings at both ends of your steel line and or your check valve leaving your compressor that can be plugged up. Any one or a combination of the above mentioned has to be the problem if otherwise your system is holding pressure.
Good luck, Mike
From: l129bs(at)gmail.com
Subject: Re: loss of main air
Date: Tue, 28 Oct 2014 09:45:13 +0900
To: yak-list(at)matronics.com
snot valve not seating properly.
On Oct 28, 2014, at 3:19 AM, Philip Nicholson <pednicholson(at)gmail.com (pednicholson(at)gmail.com)> wrote:
[quote]Hello,
I have replaced my main air valve and flap handle valve recently. No issues immediately thereafter. Air system behaved normally.
A month later, and three flights in a row, I have not been able to generate over 30 bars. It just stays there. When I land, I bleed off an additional five with flaps and brakes etc. With the engine off and Main air open, I use an external tank to fill to 50 bars. I hear no hissing whatsoever. Also of note, my snot valve after landing has little to no pressure. Goo just slowly drips/oozes out.
Any thoughts on where to start?
Thanks,
Phil Nicholson
CJ6A - C-FEPN
pednicholson(at)gmail.com (pednicholson(at)gmail.com)
| Quote: |
href="http://www.matronics.com/Navigator?Yak-List">http://www.matronics.com/Navigator?Yak-List
href="http://forums.matronics.com/">http://forums.matronics.com
href="http://www.matronics.com/contribution">http://www.matronics.com/contribution
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rget="_blank">http://www.matronics.com/Navigator?Yak-List
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mark.bitterlich(at)navy.m
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| Posted: Tue Oct 28, 2014 5:00 am Post subject: loss of main air |
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If you happen to have a source of compressed air (no more than 750 PSI, but even less will work, and the correct adapter fittings, do this:
Disconnect any fitting downstream of the snot valve, .... even at the snot valve itself is OK... on the downstream side.
Connect the air to blow BACKWARDS through the snot valve to the engine air compressor.
After you apply pressure, listen for leaks and use whatever method you have on hand to find them. This will find most leaks, including at the Banjo fitting, without having to take the whole mess apart. Remember that if you take the whole Banjo fitting apart, you are going to need new aluminum crush washers. If you fail to replace them, you are just asking for more leaks. Trust me on this one. You can tighten them up and POSSIBLY get them to seal again, but just not a wise move.
I've done the above to find leaks in this section more than once on Yaks and Sukes, but never on a CJ. Never worked on a CJ sorry to say.
If you can't find any leaks, and you cannot get the thing to pressurize, then you probably have the one way poppet valve in the Banjo itself that is not seating, and air is going back into the compressor itself. Again all the previous advice from everyone else is correct, take it apart and clean it thoroughly.
Mark
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yakxx21
Joined: 10 Jun 2012
Posts: 22
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| Posted: Sun Nov 09, 2014 2:07 am Post subject: Re: loss of main air |
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How can I drop my pressure from 65 down to a more relaxed 50.
I also feel scared of the high pressure ...prefer to be lower...can I just ad washers to the relieve valve and if so any particular type etc...??
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dsavarese0812(at)bellsout
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| Posted: Sun Nov 09, 2014 6:22 am Post subject: loss of main air |
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Loosen the jam nut on pressure relief/pop-off valve and rotate the "top hat" of the pressure relief valve counter clockwise. A good rule of thumb is approximately 1/2 turn for every 5 atmospheres you want the pressure to go down. Same method for increasing the pressure too.
Dennis
From: yakxx21 <ken(at)aeroalgarve.com>
To: yak-list(at)matronics.com
Sent: Sunday, November 9, 2014 4:07 AM
Subject: Re: loss of main air
--> Yak-List message posted by: "yakxx21" <ken(at)aeroalgarve.com (ken(at)aeroalgarve.com)>
How can I drop my pressure from 65 down to a more relaxed 50.
I also feel scared of the high pressure ...prefer to be lower...can I just ad washers to the relieve valve and if so any particular type etc...??
Read this topic online here:
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yakxx21
Joined: 10 Jun 2012
Posts: 22
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| Posted: Sun Nov 09, 2014 6:34 am Post subject: Re: loss of main air |
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Oh..that's straight forward..thanks....
Is there any way to let the air out without putting the brake on and a thousand times ??
Cheers
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dsavarese0812(at)bellsout
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| Posted: Sun Nov 09, 2014 6:42 am Post subject: loss of main air |
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Turn the main air valve on and move the flaps up and down a few times.
| Quote: | A. Dennis Savarese
334-546-8182 (mobile)
www.yak-52.com
Skype - Yakguy1 |
On 11/9/2014 8:34 AM, yakxx21 wrote:
[quote] [b]
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yakxx21
Joined: 10 Jun 2012
Posts: 22
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| Posted: Sun Nov 09, 2014 9:39 am Post subject: Re: loss of main air |
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No flaps ..l yak 50😫
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dsavarese0812(at)bellsout
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| Posted: Sun Nov 09, 2014 3:56 pm Post subject: loss of main air |
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Then you'll have to squeeze the brakes. Heck all you have to drop is 5-10 atm's. No big deal.
Dennis.
Sent from my iPhone
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mark.bitterlich(at)navy.m
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| Posted: Mon Nov 10, 2014 6:57 am Post subject: loss of main air |
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If you don't care to use the brakes there is another way, but using the brakes is a much better idea! Safer too!
My Yak-50 does not have air brakes, they have been converted to hydraulic toe brakes, so I had to come up with a simple way to do what you are trying to do.
If you look at the pressure relief/pop-off valve that Dennis has described, you will note that it is connected to an assembly of one way check valves with a filter in the middle. This assembly looks like the letter "H" with a check valve in each half leg of the letter "H". This is the central "meeting point" of all the air line in the YAK-50. One line comes in from the engine air compressor and goes through a check valve, another line comes in from the external fill port, and goes through a check valve. Then you have lines going OUT of the "H" each one ALSO through a check valve, and one of these goes to your main air bottle and one of these goes to your emergency air bottle.
The two going OUT are most AWAY from the pressure relief/pop-off valve, I.E. they are the two that are closest to the middle of the firewall and the two are aligned vertically.
One line goes out going UP and the other line goes out coming DOWN. The question is which goes to which, I ALWAYS forget.....so I have them MARKED in my airplane! What you do is to carefully remove the safety wire to the lines that screw onto the actual check valves. These are aluminum lines that you remove with a wrench. You want to be very very careful here. If they are tight, do not just put a wrench on these fittings and apply Gorilla force! You will end up twisting the whole assembly, bending lines and fixtures in the process. If you look closely you can see where you can put another wrench on the check valve itself so that as you turn the one open end wrench, you can apply opposite force on the other wrench to keep from bending the whole mess up!
Now realize that this whole thing is somewhat dangerous. You are messing with lines that have OVER 800 PSI on them, if you have those bottles filled to "6" on the gage, which represents 60 atmospheres. Wear goggles. Be careful. You only want to crack open these lines just a tiny bit until you hear air hissing. You can then slowly bleed down both the MAIN and the EMERGENCY bottles (one fitting at a time) since if you have one filled to 60, you should have them BOTH filled to 60, since the YAK-50 pressurizes both bottles from the engine compressor, unlike the 52 which only fills the main bottle from the engine compressor.
Please exercise extreme caution when doing this... Or..... Better yet, let an A&P do it.
Mark
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ronpenrose
Joined: 16 Jul 2014
Posts: 15
Location: Kansas City Metro (KLXT)
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| Posted: Mon Nov 10, 2014 6:52 pm Post subject: Re: loss of main air |
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Phil, I had nearly identical situation recently. After contacting Dennis he suggested I first look from compressor to snot. In short the problem was leeking banjo fitting and b nut at other end attaching to snot valve. Tightened both and I am now getting 50 bars.
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Ron Penrose
YAK-52 N352BW |
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Viperdoc
Joined: 19 Apr 2014
Posts: 484
Location: 08A
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| Posted: Tue Nov 11, 2014 1:02 pm Post subject: loss of main air |
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Another option. Counter clockwise one turn to adjust your PPP off valve then go fly the plane. Between start and taxi you will bleed the tank down 1-1.5 ATM. AND, you having fun too.
Doc
Sent from my iPad
[quote] On Nov 10, 2014, at 8:56 AM, Bitterlich, Mark G CIV NAVAIR, WD <mark.bitterlich(at)navy.mil> wrote:
If you don't care to use the brakes there is another way, but using the brakes is a much better idea! Safer too!
My Yak-50 does not have air brakes, they have been converted to hydraulic toe brakes, so I had to come up with a simple way to do what you are trying to do.
If you look at the pressure relief/pop-off valve that Dennis has described, you will note that it is connected to an assembly of one way check valves with a filter in the middle. This assembly looks like the letter "H" with a check valve in each half leg of the letter "H". This is the central "meeting point" of all the air line in the YAK-50. One line comes in from the engine air compressor and goes through a check valve, another line comes in from the external fill port, and goes through a check valve. Then you have lines going OUT of the "H" each one ALSO through a check valve, and one of these goes to your main air bottle and one of these goes to your emergency air bottle.
The two going OUT are most AWAY from the pressure relief/pop-off valve, I.E. they are the two that are closest to the middle of the firewall and the two are aligned vertically.
One line goes out going UP and the other line goes out coming DOWN. The question is which goes to which, I ALWAYS forget.....so I have them MARKED in my airplane! What you do is to carefully remove the safety wire to the lines that screw onto the actual check valves. These are aluminum lines that you remove with a wrench. You want to be very very careful here. If they are tight, do not just put a wrench on these fittings and apply Gorilla force! You will end up twisting the whole assembly, bending lines and fixtures in the process. If you look closely you can see where you can put another wrench on the check valve itself so that as you turn the one open end wrench, you can apply opposite force on the other wrench to keep from bending the whole mess up!
Now realize that this whole thing is somewhat dangerous. You are messing with lines that have OVER 800 PSI on them, if you have those bottles filled to "6" on the gage, which represents 60 atmospheres. Wear goggles. Be careful. You only want to crack open these lines just a tiny bit until you hear air hissing. You can then slowly bleed down both the MAIN and the EMERGENCY bottles (one fitting at a time) since if you have one filled to 60, you should have them BOTH filled to 60, since the YAK-50 pressurizes both bottles from the engine compressor, unlike the 52 which only fills the main bottle from the engine compressor.
Please exercise extreme caution when doing this... Or..... Better yet, let an A&P do it.
Mark
--
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Viperdoc
Joined: 19 Apr 2014
Posts: 484
Location: 08A
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| Posted: Tue Nov 11, 2014 1:59 pm Post subject: loss of main air |
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Apple Autocorrect? WTF is PPP off valve?!! Supposed to say pop off valve!
Doc
Sent from my iPad
[quote] On Nov 11, 2014, at 3:02 PM, Roger Kemp <f16viperdoc(at)me.com> wrote:
Another option. Counter clockwise one turn to adjust your PPP off valve then go fly the plane. Between start and taxi you will bleed the tank down 1-1.5 ATM. AND, you having fun too.
Doc
Sent from my iPad
> On Nov 10, 2014, at 8:56 AM, Bitterlich, Mark G CIV NAVAIR, WD <mark.bitterlich(at)navy.mil> wrote:
>
>
>
> If you don't care to use the brakes there is another way, but using the brakes is a much better idea! Safer too!
>
> My Yak-50 does not have air brakes, they have been converted to hydraulic toe brakes, so I had to come up with a simple way to do what you are trying to do.
>
> If you look at the pressure relief/pop-off valve that Dennis has described, you will note that it is connected to an assembly of one way check valves with a filter in the middle. This assembly looks like the letter "H" with a check valve in each half leg of the letter "H". This is the central "meeting point" of all the air line in the YAK-50. One line comes in from the engine air compressor and goes through a check valve, another line comes in from the external fill port, and goes through a check valve. Then you have lines going OUT of the "H" each one ALSO through a check valve, and one of these goes to your main air bottle and one of these goes to your emergency air bottle.
>
> The two going OUT are most AWAY from the pressure relief/pop-off valve, I.E. they are the two that are closest to the middle of the firewall and the two are aligned vertically.
>
> One line goes out going UP and the other line goes out coming DOWN. The question is which goes to which, I ALWAYS forget.....so I have them MARKED in my airplane! What you do is to carefully remove the safety wire to the lines that screw onto the actual check valves. These are aluminum lines that you remove with a wrench. You want to be very very careful here. If they are tight, do not just put a wrench on these fittings and apply Gorilla force! You will end up twisting the whole assembly, bending lines and fixtures in the process. If you look closely you can see where you can put another wrench on the check valve itself so that as you turn the one open end wrench, you can apply opposite force on the other wrench to keep from bending the whole mess up!
>
> Now realize that this whole thing is somewhat dangerous. You are messing with lines that have OVER 800 PSI on them, if you have those bottles filled to "6" on the gage, which represents 60 atmospheres. Wear goggles. Be careful. You only want to crack open these lines just a tiny bit until you hear air hissing. You can then slowly bleed down both the MAIN and the EMERGENCY bottles (one fitting at a time) since if you have one filled to 60, you should have them BOTH filled to 60, since the YAK-50 pressurizes both bottles from the engine compressor, unlike the 52 which only fills the main bottle from the engine compressor.
>
> Please exercise extreme caution when doing this... Or..... Better yet, let an A&P do it.
>
> Mark
>
>
> --
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yakxx21
Joined: 10 Jun 2012
Posts: 22
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| Posted: Fri Nov 14, 2014 7:22 am Post subject: Re: loss of main air |
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Thanks guys....excellent and I did all that and found that one of the non return valves was leaky...
stripped it and found one of the crush Ali washers was broken....but how to get a replacement ?? so I machined one up to size but it was 1.2mm thick....the original is 0.5.
So I put the one I made up in and put it all back together,,,didnt work ...non return.....returned !
stripped it again and having spent hours rubbing down the washer to the right thicknes , it nor works fine...so I have learnt that the thickness is critical.
Question ..where can I buy some correct Crush washers and a new o ring seal ...(I think the O ring is standard) the washers are soft Ali and are 20x16x0.5
If anybody can guid me I would appreciate it because I would really like it back as original....
Finally...anybody know where to buy a new Air main tank...mine looks a bit grotty inside..Im told they all look a bit corroded but I sure dont like it and would like to buy a new one....
hungarian guys sell used ones...not good.
Tried the usual UK sources but seems cannot get one ...I think its 6 or 7 litres...
any leads ...again much appreciatied
Good Yaking
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