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Author Topic: Leak from below  (Read 7999 times)

ghancock

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Leak from below
« on: February 23, 2016, 11:33:16 am »
For the last few flights I've been having problems with skydrol blowing all under the plane and haven't been sure where it was coming from.  I'm in the process of pulling up the floor again and need to do this anyway because I need to clean the skydrol out of the plane.  However, after searching a bit it appeared to be coming from up towards the front landing gear area.  Nothing was wet up there though so the search continued.

We then discovered the left rudder pedal boot on the pilot side was completely soaked in skydrol and already had holes in it.  I still can't figure out how that much skydrol got down inside the boot itself but Morris says it runs down the pedal linkage arm and just collects there until it eventually just starts running into the belly.

I noticed the left master cylinder for the brake leaking a little the other day when we were investigating the locked up brake problem but didn't think it was that severe since the floor under it had no skydrol on it at all.  I'm still baffled by this and will let you know if I find something else once I pull the floor up.

However, last night I removed the brake cylinder from the plane and took it apart and here are a few pictures.  The cylinder has grooves in it and the piston is scared pretty good.  The o-rings seemed fairly new though so not sure how it got in such bad shape.  Perhaps the shop in Athens put new o-rings in it and put it back together in such bad condition.  It seems like they did do something there but not 100% and not really on talking terms with them anymore.

Anyway, here are a few pics:

« Last Edit: February 23, 2016, 11:34:47 am by ghancock »
--glenn
You can't win an argument with an ignorant person,  they'll just drag you down to their level and beat you with experience.

Willis

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Re: Leak from below
« Reply #1 on: February 23, 2016, 12:51:03 pm »
Those wear marks are not recent.  It looks like the 'rest' position of the piston/o-ring, where your feet 'dither' a little.

Check the o-rings are the right material.  Those guys may have not used ones compatible with skydrol. 

B
-Bud

ghancock

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Re: Leak from below
« Reply #2 on: February 23, 2016, 01:04:46 pm »
Thanks, I don't know how to check the o-rings other than they are still very solid and if not the right ones they would be like jelly.  They have color markings on them still but don't know how to read them ( if they have meaning ).

Morris thinks the entire assembly is shot and is sending me one he's rebuilding now to replace it.  I also agree there is no way those marks got there in 10 hours of flying it.

Glenn
--glenn
You can't win an argument with an ignorant person,  they'll just drag you down to their level and beat you with experience.

ghancock

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Re: Leak from below
« Reply #3 on: March 07, 2016, 09:30:30 pm »
Got new cylinder in after leaking a gallon of expensive skydrol all over the floor while it ran down my arms.  Just could not get the one pressure side of the fitting to line up correctly and having slimmy skydrol all over your hands makes it an effort that requires a few choice words while working. 

At the moment it doesn't appear to be leaking so keeping my fingers crossed.  It is messy enough dealing with skydrol but knowing each gallon is over $130 doesn't make the effort any less stressful.

If I ever get all of the hydraulic leaks stopped I think it will be shocked.  It seems like every leak I stop I kickup 2 more.  Driving me crazy atm.

Glenn
--glenn
You can't win an argument with an ignorant person,  they'll just drag you down to their level and beat you with experience.

aerocheck

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Re: Leak from below
« Reply #4 on: March 07, 2016, 10:21:03 pm »
I think Willis already posted some of this information in another subject but thought it might be useful here as well for somebody in the future

Here is a compatibility chart for O-Ring Materials - www.oringsusa.com is a great source for O-Rings - http://oringsusa.com/html/compatibility.html

Ray Wolfe
Deerfield Beach, FL

ghancock

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Re: Leak from below
« Reply #5 on: March 08, 2016, 09:48:39 am »
Yeah, but thanks and I'm sure someone will be looking for it again one day. :-)

Glenn
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You can't win an argument with an ignorant person,  they'll just drag you down to their level and beat you with experience.

Davidwheep

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Leak from below
« Reply #6 on: June 23, 2017, 09:14:18 am »
I've experienced the same thing, I haven't identified where the leak is coming from. I thought I may have overfilled the it.


Supershooter

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Re: Leak from below
« Reply #7 on: June 23, 2017, 11:08:26 am »
Hope you get it fixed, Glenn.  I, too, have had a few residual problems from the Athens work.  Lots of things redone...

You've earned a few months of problem-free flying!

Ed
Ed

ghancock

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Re: Leak from below
« Reply #8 on: July 08, 2017, 08:53:13 am »
Well,  as it turned out the hose that was installed to the steering actuator had gotten kinked and was leaking.  I suspect it only leaked when the gear was up which is why the leak was only at the back of the doors and there were no other signs of anything.  I installed 2 new hoses and routed them the way they were supposed to be routed and hopefully that will fix the issue.

I just need to get the damn plane flying again.

Glenn
--glenn
You can't win an argument with an ignorant person,  they'll just drag you down to their level and beat you with experience.