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T-6 Hydraulic Reservoir Mod

Tue Oct 06, 2015 8:57 pm

I'm looking for some intel on this Mod as there is a T-6 in need of it. He has Red Line Brakes and they went out. We tried to bleed them and were able to get the right side to come back but the left side is still out to lunch. We were told about this mod and thinking it will help him down the road.

Thanks in Advance,

Lynn

Re: T-6 Hydraulic Reservoir Mod

Wed Oct 07, 2015 11:22 am

Is the brake master cylinder even connected to the main hydraulic reservoir, or is that the modification?

Re: T-6 Hydraulic Reservoir Mod

Wed Oct 07, 2015 1:54 pm

As far as i know, the original Models AT6-A to -F had a small Standpipe Reservoir on the Master Brakecylinder and used Castor based Brake Fluid. On the T-6G Model this was changed to the 5606 Fluid (Fluid 4) allready used in the Hydraulic System, by simply adding another Fitting to the Hydraulic Reservoir and connecting it to the Master Brakecylinders Reservoir.
I am not aware of any other Mod either.

Best regards

Stefan

Re: T-6 Hydraulic Reservoir Mod

Wed Oct 07, 2015 3:33 pm

I was told that one would use a reservoir from a Bell 47 helo and you would attach it to the brakes. I was hoping that Stoney would chime in on this one...

Re: T-6 Hydraulic Reservoir Mod

Wed Oct 07, 2015 6:04 pm

Lynn, we pressure bled the brakes from the top down. I made an adapter by using a clear hose on a barbed fitting with the same pipe thread as the standpipe. I remove the standpipe and screw the fitting into the elbow, connect it to our pressure pot and just crack open the valve on the pot. Then open the bleeder on the wheel cylinder and then open the pot valve a little more. Once any air is forced out just close the bleeder on that wheel and open the one on the other wheel. Lose a little removing the fitting and re-attaching the standpipe but not enough to be an issue. I usually hold the hose vertical and unscrew it with the standpipe close by. A rag under the elbow keeps it from being to much of a mess. Works pretty good.

Re: T-6 Hydraulic Reservoir Mod

Thu Oct 08, 2015 1:21 pm

Learned something new...

Find Number 36-27
Part Number 168-58801-17 (? hard to read on my copy)
Line Assembly - Hydraulic brake supply firewall elbow to master brake cylinder

Find Number 36-29
Part Number 121-58026-11
Line Assembly - Hyd brake supply reservoir to firewall elbow
Attachments
BrakeB.JPG
From T.O.No.1T-6G-2
BrakeA.JPG
From T.O.No.1T-6G-2

Re: T-6 Hydraulic Reservoir Mod

Thu Oct 08, 2015 10:02 pm

CraigQ wrote:Lynn, we pressure bled the brakes from the top down. I made an adapter by using a clear hose on a barbed fitting with the same pipe thread as the standpipe. I remove the standpipe and screw the fitting into the elbow, connect it to our pressure pot and just crack open the valve on the pot. Then open the bleeder on the wheel cylinder and then open the pot valve a little more. Once any air is forced out just close the bleeder on that wheel and open the one on the other wheel. Lose a little removing the fitting and re-attaching the standpipe but not enough to be an issue. I usually hold the hose vertical and unscrew it with the standpipe close by. A rag under the elbow keeps it from being to much of a mess. Works pretty good.


Just about what we had, it looked more like a IV bottle. Ozarka water bottle with a clear hose and we lost a lot of fluid and made a mess...

Re: T-6 Hydraulic Reservoir Mod

Thu Oct 08, 2015 10:02 pm

bdk wrote:Learned something new...

Find Number 36-27
Part Number 168-58801-17 (? hard to read on my copy)
Line Assembly - Hydraulic brake supply firewall elbow to master brake cylinder

Find Number 36-29
Part Number 121-58026-11
Line Assembly - Hyd brake supply reservoir to firewall elbow



Thank you...

Re: T-6 Hydraulic Reservoir Mod

Fri Oct 09, 2015 11:52 am

Lynn Allen wrote:
CraigQ wrote:Lynn, we pressure bled the brakes from the top down. I made an adapter by using a clear hose on a barbed fitting with the same pipe thread as the standpipe. I remove the standpipe and screw the fitting into the elbow, connect it to our pressure pot and just crack open the valve on the pot. Then open the bleeder on the wheel cylinder and then open the pot valve a little more. Once any air is forced out just close the bleeder on that wheel and open the one on the other wheel. Lose a little removing the fitting and re-attaching the standpipe but not enough to be an issue. I usually hold the hose vertical and unscrew it with the standpipe close by. A rag under the elbow keeps it from being to much of a mess. Works pretty good.


Just about what we had, it looked more like a IV bottle. Ozarka water bottle with a clear hose and we lost a lot of fluid and made a mess...


Yeah I can see how that would be a mess. We have a small metal tank for a fluid reservoir we can pressure with air with a shut off valve. I can pressure the master from the top down with this and shut the valve off. This way there is only a couple of teaspoons of fluid in the line to deal with. Sounds like ya'll have a stubborn air bubble in the left wheel brake assy. May take more than just brake pedal pressure to make it move.

Re: T-6 Hydraulic Reservoir Mod

Fri Oct 09, 2015 10:24 pm

sometimes with real stubborn air bubbles, you might think about putting the plane on jacks and retracting the gear,then bleed the system.

Re: T-6 Hydraulic Reservoir Mod

Sat Oct 10, 2015 5:15 am

Matt Gunsch wrote:sometimes with real stubborn air bubbles, you might think about putting the plane on jacks and retracting the gear,then bleed the system.


Roger that and thanks...

Re: T-6 Hydraulic Reservoir Mod

Thu Oct 22, 2015 9:40 pm

Try taking the calipers loose and let them hang vertically for an hour or so. It will let any air trapped to move up the brakline to the master cylinder. Worked on mine after numerous attempts at bleeding.

Re: T-6 Hydraulic Reservoir Mod

Sat Oct 24, 2015 9:15 pm

Smaehr wrote:Try taking the calipers loose and let them hang vertically for an hour or so. It will let any air trapped to move up the brakline to the master cylinder. Worked on mine after numerous attempts at bleeding.


Roger that as well, last I heard they were working fine. Must have been the 3-4 monkeys on the football working on it...
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