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Author Topic: Hydraulic leak?  (Read 4738 times)

Adam Frisch

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Hydraulic leak?
« on: July 14, 2018, 11:30:42 pm »
Last hour on the flight yesterday a hissing sound came on. I tried to locate where it came from in the air, but it was too loud to pinpoint. After landed, found a little pool of hydraulic fluid on top of floor just behind piedestal, between the seats. Bizarre how it showed up there, so it got me thinking maybe there was a leak under the floor that somehow sprayed upwards and come out between the sealant for one of the floor inspection panels? And the leak caused the hissing? Possible? What kind of hydraulic lines are normally right beneath the floor and between the pilots seats?

Another thing that makes me suspect this is that hyd level was low, flaps droop quicker than they used to after sitting and when the hydraulic pump actuates when you press the breaks, the pressure drops quicker than it used to. Indicative of a leak, or something else? Low nitrogen?

I hate hydraulics. Always a pain on every plane I've owned.  :(
« Last Edit: July 17, 2018, 03:34:26 pm by Adam Frisch »
Slumming it in the turboprop world - so you don't have to.

Bruce Byerly

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Re: Hydraulic leak?
« Reply #1 on: July 16, 2018, 10:04:07 pm »
Uh oh.  Find the leak.  The gear/flap selector is in that area.  I hope you don’t have a belly full of fluid so don’t let it go. 

Any luck with local guy Dan for some maintenance? 

Seems like you are making some progress but the bad thing about sitting around for a couple years is this kind of stuff. 

Adam Frisch

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Re: Hydraulic leak?
« Reply #2 on: July 17, 2018, 03:39:39 pm »
Thanks Bruce. Yes, spoke to Dan. Couldn't replicate fuel leak, so probably just fly her over there with the aux hyd pump breaker pulled and have him look for that leak. Looks like I'll be taking her to AeroAir later for the rest of the stuff, but afraid to fly her that far without knowing exactly if there's a leak or not. I'll figure it out.
Slumming it in the turboprop world - so you don't have to.

av8r

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Re: Hydraulic leak?
« Reply #3 on: July 25, 2018, 05:20:54 pm »
Adam, please take Bruce's advice and have that hydraulic leak inspected ASAP. Bruce is correct about the location of the Flap/Gear control valve. It is mounted on the floor directly beneath the throttle quadrant. Not knowing exactly which model you're flying can't comment too much but don't believe pulling the aux hydraulic CB is going to help. That pump is mounted in the left wheel well on most models. The concern here is the presence of hydraulic fluid in the cockpit. 5606 is a extremely flammable substance and potentially having the belly full of it is not something you want to do. If you are using 83282 you are a bit better off but not much.

Adam Frisch

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Re: Hydraulic leak?
« Reply #4 on: July 25, 2018, 11:50:59 pm »
Dropped her off last week at Chino to check on this. Haven't heard anything yet.
Slumming it in the turboprop world - so you don't have to.