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Author Topic: Pressurization Leak  (Read 2554 times)

seanmcgillivray

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Pressurization Leak
« on: November 17, 2021, 07:57:38 am »
Yesterday climbing thru 17k I noticed a high pitch "squeal" and noticed my diff was 5 PSI and the cabin was climbing. I returned down to 15k and commanded the cabin to SL and could only get 4.5 PSI and a 2.5-3k cabin. Clicking on Mass Flow would raise the PSI to 5ish and the squeal would get louder.

I am suspecting the power brake valve boot. Mine look original with silicone slathered on them. I cleaned them the best I can on the ramp and added RTV (couldn't find any PRC).

Anyone change these? I have EAC getting parts and going to try and limp home low on Friday.

Adam Frisch

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    • Adam Frisch FSF
Re: Pressurization Leak
« Reply #1 on: November 18, 2021, 12:37:20 am »
Could be anything in the forward firewall or under the panel. Column boot, avionic or electric pass-thru's, outflow valve etc. It can be a pain in the ass to find.
Slumming it in the turboprop world - so you don't have to.

Bruce Byerly

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Re: Pressurization Leak
« Reply #2 on: November 20, 2021, 09:07:33 pm »
You’ll find it quickly with a pressurization cart and a competent service center.

seanmcgillivray

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Re: Pressurization Leak
« Reply #3 on: November 20, 2021, 10:40:38 pm »
ECA got me up to full diff, but assume when reviving the old airplane the path of least resistance will show itself. Got a service kit and boots shipping this week.