Valves And Valve Components - Polaris 1999 Sportsman 400 Service Manual

ENG INE TOP END 113
CAUTION
The four larg e bolts must be tight-
ened. loosened. then light en aga
in ill
the fo llowing sequence to
provide
a
good seal and
to prevent damage.
8. Tighten the four larger bolts (F igure 81) in a
crossing pattern evenly in the following steps. Mark
a line on the large bolts (Fig ure 82) for a degree ref-
erence:
a. Tighten to 30 Nom (22 ft.-lb.).
b. Tighten to 70 Nom (5 1 It .-lb.).
c. Loosen each of the four bolts exactly 180'
( 1/2 tum).
d. Loosen each of the four bolts again exactly
180' ( 1/2
tum) .
e. Tighten to 15 Nom ( I I ft.-lb.).
f. Tighten each of the four bolts exactly 90'
(1/4
tum).
g. Finally, tighten each of the four bolts exactly
90' (114 tum) more.
9. Tighten the two small 6 rnrn bolts (8, Figure 79)
to 8 Nom (71 in. lb.).
10. Install the camshaft (Chapter Six), rocker am,
assembly and cylinder head cover (this chapter).
I I. Install the carburetor (Chapter Six) and the ex-
haust pipe to the cyli nder head.
VALVES AND VALVE COMPONENTS
Co mple te valve se rvice requires a numb er o f spe -
cial tools. The following procedures describe how
to check for valve component wear and to deter-
mine what type of service is required. A valve
spring compressor is requiredto remove and install
the va lves.
II