I got an E-Mail from Mal that someone was requesting
this a few days back. I missed the thread, but am
posting here. Here's the seal and valve repair procedure:
If it's just the adjustment, it's a quick fix:
Here's photo's of when I repaired Mal's 777. If you
take it apart, replace the seals and the valve:
Remove the handgrip screw
Remove other handgrip screw. MAKE SURE THE SAFETY IS ON
OR THE SAFETY SPRING AND BEARING WILL FLY OUT WHEN OPENED!
Remove upper receiver screws
Seperate piston/barrel assembly. Remove the cocking arm
Remove barrel, front sight and piston from chamber.
unscrew old valve and remove old seals and felt washer
The new valve is rounded. The old valve is worn almost
conical. The felt washer disentegrated.
New seals and valve installed. Old seals and valve
Apply a touch of Moly Paste to the seals
Assemble in reverse order. Pay special attention to
the silver safety lever position in the bolt
After repair, with Lemon Oil hand rubbed into the
Trigger before (777 and 747 triggers
are adjustable by the small screw on the front of
the handgrip frame) adjustment