Tecumseh VLV - Chapter 11 VALVES, LIFTERS, SPRING & VALVE SEATS; VALVES; VALVE REMOVAL; VALVE SEATS

30
Second, use the 31
o
cutter to clean and narrow the seat
from the top toward the center.
Seats are ground at an angle of 46
o
, to a width of 3/64'’.
Valves are not identical. Make sure the valve marked
“EX” or “X” is installed in the exhaust valve location,
and the valve marked “I” is installed in the intake valve
location. If the valves are unmarked, the nonmagnetic
valve is installed in the exhaust valve location.
VALVES. Valves must be in good condition, proper
sealing and proper gap must be maintained for full
power, easy starting and efficient operation.
VALVE REMOVAL. To remove valves, use a
commercially available valve spring compressor. Move
the lower cap, so it will slip off the end of the valve.
Clean all parts and remove carbon from valve heads
and stems. If valves are in usable condition, grind the
valve faces to a 45
o
angle. Replace valves if they are
damaged, distorted or if the margin is ground to less
than 1/32'’.
SEAL CUTTER
BOTTOM
NARROWING
BOTTOM
NARROWING
CUTTER
SEAT
60
o
15
o
TOP
NARROWING
CUTTER
Ú
Ú
Ú
SEAT
Ù
Ù
46
o
31
o
Ú
3/64"
SEAT
31
o
46
o
Ù
Ù
Ù
Ù
MARGIN
45
o
FACE
STEM
VALVE SEATS. Valve seats are not replaceable. If
they are burned or pitted, they can be reground using a
grinding stone or valve seat cutter.
SEE SPECIFICATIONS
SECTION FOR DIMENSIONS
INTAKE
VALVE
EXHAUST
VALVE
46
o
The recommended procedure to properly cut a valve
seat is to use the Neway Valve Cutting System, which
consists of three different degree-cutters. First, use the
60
o
cutter to clean and narrow the seat from the bottom
toward the center.
1/32" MINIMUM
DIMENSION
Chapter 11
VALVES, LIFTERS, SPRING & VALVE SEATS
Not For Resale
www.SmallEngineDiscount.com