Checking/Adjusting Valve Clearance (5000/ 9000) - Arctic Cat ZR 5000 Operator's Manual

Varying terrain conditions and operating
usage may require spark plugs of a differ-
ent heat range. For example, sustained
cross-country riding will usually require
colder heat-range spark plugs while trail
riding or other continual slow speed
operation will usually require hotter heat-
range spark plugs.
CAUTION
If adjusting spark plug gap is neces-
sary, do not use the center electrode
as a leverage point. Damage to the
plug may occur.
Removing/Installing
1. Remove the springs securing the
expansion chamber to the exhaust
manifold and resonator.
2. Move the expansion chamber out of
the way to access the spark plugs.
3. Remove the spark plug caps from
the plugs.
4. Using a spark plug wrench, remove
the plugs.
5. Install the plugs and finger-tighten.
6. Tighten the spark plugs to 19 ft-lb;
then install the spark plug caps.
7. Place the expansion chamber into posi-
tion and secure to the exhaust manifold
and resonator with the springs.
8. Install the hood.
Checking
To see if the spark plugs being used are of
the proper heat range (after the snowmo-
bile has been operated under normal driv-
ing conditions), remove the spark plugs
and examine the condition of the center
electrode insulator of each spark plug.
A. TAN or LIGHT BROWN insula-
tor indicates correct spark plugs
(heat range).
B. LIGHT GRAY or WHITE insula-
tor indicates over-heating of the
engine. This condition is caused by
a too lean condition or incorrect
spark plugs (heat range too hot).
C. BLACK insulator indicates fuel
in the combustion chamber is not
burning completely. This condi-
tion is caused by a too rich con-
dition, too much oil, or incorrect
spark plugs (heat range too cold).
NOTE: If the center electrode insu-
lators are light gray, white, or black
and if the oil-injection pump synchro-
nization and ignition timing are cor-
rect, different heat-range spark plugs
may be necessary. Authorized Arctic
Cat Snowmobile dealers have detailed
spark plug information. Consult a
dealer before changing spark plugs,
as incorrect heat-range spark plugs
could cause poor engine performance
or engine damage.
CAUTION
If a spark plug is light gray, white, or
black and another is tan or light
brown, take the snowmobile to an
authorized Arctic Cat Snowmobile
dealer for inspection and service. If
not under warranty, this service is at
the discretion and expense of the
snowmobile owner.
Checking/Adjusting
Valve Clearance (5000/
9000)
After 5000 miles or prior to seasonal
storage, valve clearance should be
checked and adjusted as necessary.
NOTE: Take the snowmobile to an
authorized Arctic Cat Snowmobile
dealer for inspection and service.
This service is at the discretion and
expense of the snowmobile owner.
CAUTION
It is critical that the checking/adjust-
ing valve clearance be done at the
recommended intervals or severe
AO352A
engine damage may occur.
35