Central locking, bodywork or electrics, pump running for 20 seconds!

[HPsauce]

The culprit!

BootLock.jpeg

When unlocking (which I can confirm is SUCK) this closes up somewhat so that generally works. The input pipe is fine.
When unlocking it just blows air out until the pump times out.
Incidentally using the valet lock just physically stops the rod moving which due to position somewhat restricts the leak but doesn't stop it.
The picture shows the UNLOCKED position, the rod is pulled in about 10mm when locked.

My thinking is that inside the unit will be a plunger which "should" have a sealing ring/washer of some sort so I guess that's also leaking.
It's not obvious how to get that unit out, or is just held by that one screw (in the picture) once the linkages are disconnected?

I wonder if a few dabs of suitable adhesive would be enough to seal that?

[HPsauce]

I wonder if a few dabs of suitable adhesive would be enough to seal that?

Well I tried my "go to" product and, for now at least, it seems to have worked after leaving to cure for about an hour.

For reference: KISS Powerflex Brush-on Nail Glue. As used by SWMBO.
It's effectively a cyanoacrylate superglue with I think some extra ingredients to make it less brittle when set.
Plus it comes in a handy bottle with a brush applicator, very useful for many repair jobs, I find it much better than tubes.

NailGlue.png

Incidentally the unit is held by two screws but getting it out looks to be a nightmare.
The long rod across between the boot latch and keylock (plus solenoid unit) all seem to be in the way and the fixings for that are under a thick black sound deadening patch. A job to be avoided if possible, plus the unit is over £100 at Prestige!

[HPsauce]

I've subsequently found an A8 Parts Forum thread from early 2020 when someone took a slightly different approach to this problem, though they did use gasket sealant as part of the solution.
See: https://forum.a8parts.co.uk/showthread.php?t=15457
Their instructions overlook the two screws in the boot lid interior handle and also seem to make light of removing the unit from its hiding place.