Seat Ring Repair; Seat Ring Inspection - Segway VILLIAN SSV Series Service Manual

CYLINDER HEAD, CYLINDER, PISTON CYLINDER HEAD, CYLINDER, PISTON
B B A A C C
D D
F F G G
H H J J
【F】Good
【G】 Too wide
【H】 too narrow
【J】 Uneven

Seat ring repair

◆ S e a t r i n g r e p a i r s h o u l d b e c a r r i e d o u t b y
professionals who are proficient in cylinder head
repair technology. Repair techniques vary, so please
follow the valve repair equipment manufacturer's
instructions. Do not over-grind the seat ring.
WARNING
!
When disassembling and reassembling the cylinder
head, wear goggles or face shield.

Seat ring inspection

◆ Remove the valve.
◆ Check the contact surface 【A】 between the valve
【B】 and the seat ring 【C】.
◆ Paint the seat ring.
◆ Push the valve into the valve guide.
◆ Use a grinding tool to press and rotate the valve
relative to the seat ring.
E E
◆ Take out the valve and check the pattern of the
contact surface on the seat ring. The width of the
entire circle must be appropriate.
◆ Measure the diameter of the outer ring of the contact
surface on the seat ring 【D】.
◆ If the outer diameter of the seat ring contact surface
is too large or too small, repair the seat ring (see
seat ring repair).
Outer diameter of seat ring contact surface
exhaust
intake
TIPS
The valve stem and valve guide must be good,
otherwise the check will be inaccurate.
◆ If the seat ring interface shape is not good, repair
the seat ring (see seat ring repair).
◆ Use a vernier caliper to measure the width of the
part without carbon deposits (bright part) on the seat
ring 【E】.
Width of contact surface of seat ring
Exhaust
intake
If the width is too wide, too narrow or uneven, repair the
valve seat (see valve seat repair)
3-5-31
31.8 ~ 31.9mm (1.2520" ~ 1.2559")
36.8 ~ 36.9mm (1.4488" ~ 1.4528")
1.5 ~ 1.6mm (0.0591" ~ 0.0630")
1.0 ~ 1.1mm (0.0394" ~ 0.0433")