Loading…
21
Struggling to get a proper seal on a cabin pressure valve after overhaul
Just finished putting a valve back on a Learjet and now it's leaking air during tests. I followed the manual but the gasket seems to sit wrong every time. It's eating up hours trying to line it up right. Any tips for getting these to seat without fighting them for days?
4 comments
Log in to join the discussion
Log In4 Comments
singh.cole6mo ago
The Lear 35 valve gaskets always shrink a bit after storage... I warm mine up with a hair dryer for a minute before fitting... makes them way more flexible. What @the_olivia said about torque sequence is key... if you crank one side down first it'll never seal right. Also, try putting a tiny smear of silicone grease on the gasket surface... helps it slide into place without binding. Sometimes the flange itself gets warped from overtightening in the past... check it with a straight edge if you have one. It's a pain but once you get the feel for it...
7
the_olivia6mo ago
Dealing with those seals is a NIGHTMARE sometimes. I had a similar issue on a different valve where the gasket would never sit flat no matter what. Try warming the gasket a bit to make it easier to shape, it can help it conform to the surface. Also, double-check the torque sequence in the manual, because overtightening one bolt first can warp the whole thing. It took me forever to figure that out, but once I did, the seal popped right into place. Hang in there, it'll click eventually.
0
logan_wells5mo ago
Yeah it's one of those jobs that looks simple but has a ton of little tricks. The torque sequence advice is spot on, I've made that exact mistake before. Once you get the process down it's not so bad.
8
simon_young466mo ago
A heat gun on low softens rubber gaskets so they conform to the surface every time.
3