Stiga WBE170 - Overhauling the Valves

Release 00 - 11/2018
Engine WBE 170
page 53
Workshop Manual
16. ENGINE BLOCK - Overhauling internal parts
16.4 Overhauling the valves
NOTE - These paragraphs describe all the
operations for checking and overhauling the
valves;
it is left to the operator to assess the advisabi-
lity of performing all the operations described
or only part of them, depending on the type
of engine problems encountered.
1 - Remove the cover and uncouple the conveyor.
2 - Open the crank case [
16.1] and remove
the piston [ 16.3].
3 - Move the rocker arms (37); press down the spring
seal cap (38) and move it sideways to remove from
the valve stem (39).
IMPORTANT - The intake and exhaust valves are of
different sizes.
4 - Use an emery cloth to remove all incrustations
from the valve head and check the thickness of the
rim (A); the valve must be replaced if the margin
(A) is less than 0,50 mm or if it shows signs of burning.
5 - Check the diameter of stem (B) in several points
and replace the valve if it is less than the following,
even if only in one point:
5,32 mm (inlet - IN)
5,27 mm (exhaust - EX)
A
B
37
38
39
<< BACK >>
INDEX