I haven't updated this thread in a while, but I've done a few bits since I last posted.
Clutch Slave Cylinder Delay Valve Removal - late August
I briefly posted about this here.
Honda call this the Delay Orifice Mechanism. Here's the description from the
ESM:
'The delay orifice mechanism improves clutch operation by delaying the slave cylinder release speed when the clutch pedal is suddenly released. The delay orifice mechanism is built into the slave cylinder.'
Allegedly, Honda and many other manufacturers added these valves to prevent transmission component damage due to slowly releasing the pressure in the CSC, but this in turn makes the clutch wear faster. It also sometimes stops aggressive/quick shifting, particularly in lower gears. I removed the delay valve because I felt the clutch was too unpredictable at high revs with quick shifts, and since removing quick shifts have been (mostly) spot on. No more grinding 1st to 2nd.
I used
this TSX and
this Civic Si thread as references/guides.
CSC location
CSC closeup
CSC removed - you'll need a flare nut spanner for the clutch line:
I used this one.
'C' clip removed - I used
this set of picks and it was a pain, but after 15 mins I got it out.
This is the delay valve removed. I've kept mine in my parts box just in case.
I then cleaned up all the parts, reinstalled the CSC and clutch line, torqued eveything properly and applied Honda Super Hi Temp Urea Grease where the CSC rod meets the release fork, as well as rubber grease to the rod boot. Finally I bled the clutch line and topped it up with additional Honda DOT 4 fluid. You will need to bleed the line as removal will introduce air.
It's been 2 months now since I completed this mod and all is good. Shifting quickly feels predictable and extremely satisfying, yet regular/slow shifting feels exactly the same - missus didn't even notice