05-24
MMC2005-001_05A.FM
SECTION 05 - ENGINE PREPARATION
TUNING THE MAIN JET SYSTEM
Before operating the snowmobile, make sure all
parts, including clutch and drive belt, are in good
operating condition.
1. Operate snowmobile at wide open throttle for
several minutes on a flat, well packed surface.
Change main jet if snowmobile fails to achieve
maximum RPM or labors at high RPM.
2. Continue to operate at wide open throttle and
shut off ignition before releasing throttle. Exam-
ine exhaust manifold and spark plugs to deter-
mine if fuel/air mixture is too lean.
NOTE:
Do not change jet sizes by more than one
increment (step) at a time.
3. If the exhaust manifold or spark plug insulator
is dark brown or black, the fuel/air mixture is too
rich. Decrease jet size.
4. If the exhaust manifold or spark plug insulator
is very light in color, the fuel/air mixture is too
lean. Increase jet size.
5. If you cannot determine the color, proceed as if
fuel/air mixture were too lean and increase jet
size. If operation improves, continue to increase
jet size to obtain peak performance. If operation
becomes worse, decrease jet size to obtain peak
performance.
6. After proper main jet is selected, recheck jet
needle and needle jet.
Troubleshooting
When the carburetor setting is not correct for the
engine, various irregularities are noticed. These
can be traced to two causes as a whole:
1. When the air/fuel mixture is too rich:
a. The engine noise is full and intermittent (four
stroking).
b. The condition grows worse when the enrich-
ner is opened.
c. The condition grows worse when the engine
gets hot.
d. Removal of the air cleaner will somewhat im-
prove the condition.
e. Exhaust gases are heavy.
f. Spark plug is fouled.
2. When the air/fuel mixture is too lean:
a. The engine overheats.
b. The condition improves when the enrichner
is opened.
c. Acceleration is poor.
d. Spark plug electrodes are melted.
e. The revolution of the engine fluctuates and a
lack of power is noticed.
f. Piston seizure or scuffing occurs.
47.5
A01C4LA
50
75
100
Throttle valve opening (%)
Fuel flow
+ 20 - 22 (%)
+ 8 - 10 (%)
+ 8 - 10 (%)
+ 20 - 22 (%)
Содержание ski-doo MACH Z 1000 SDI
Страница 1: ...Mmc 2005 001 Racing FH8 Wed Sep 15 15 27 01 2004 Page 1 C M Y CM MY CY CMY K...
Страница 118: ...04 36 MMC2005 001_04A FM SECTION 04 SUSPENSION SC 3 SC 4 RAS SC IV REAR SUSPENSION 0...
Страница 124: ...04 42 MMC2005 001_04A FM SECTION 04 SUSPENSION SC 3 SC 4 RAS...
Страница 196: ...05 72 MMC2005 001_05A FM SECTION 05 ENGINE PREPARATION FUEL TANK AND FUEL PUMP All Models except SDI 2 4 3 1 A33C2VS...
Страница 289: ...SECTION 06 DRIVE SYSTEM MMC2005 001_06A FM 06 27 422 A01D3JA 417 222 562 427 A01D3KA 417 222 677...
Страница 473: ...SECTION 12 SERVICE TOOLS MMC2005 001_12A FM 12 29 N Scratch remover P N 861 774 800 APPLICATION All models...
Страница 476: ...MMC2005 001_13A FM 13 1 SECTION 13 ACCESSORIES TABLE OF CONTENTS 0 ACCESSORIES 13 02...
Страница 493: ...Mmc 2005 001 Racing FH8 Wed Sep 15 15 27 01 2004 Page 1 C M Y CM MY CY CMY K...