Snowmobile Arctic Cat (2008 year). Manual - part 19

2-13

2

5. Assemble the crankcase halves making sure the

crankcase dowel pins are properly positioned and

the end seal tab will not block the oil transfer port

in the upper crankcase half.

AB092A

6. Install the crankcase cap screws making sure the

cap screws are in the corresponding-sized holes.

Tighten in three steps the 8 mm cap screws to 18

ft-lb and the 6 mm cap screws to 8 ft-lb using the

pattern shown.

0726-412

„NOTE: Secure the connecting rods with rubber
bands on the cylinder studs.

B160

7. Install the piston rings on each piston so the letter

on the top (inclined surface) of each ring faces the

dome of the piston.

726-306A

AC088

8. Apply oil to the connecting-rod small-end bear-

ings; then install the small-end bearings into the

connecting rods.

„NOTE: Apply oil to the piston pin before installing.

9. Place each piston over the connecting rod so the

arrow on the piston dome points toward the

exhaust port; then secure with a piston pin.

„NOTE: The arrow is found either up inside the
piston or on the dome top.

10. Install the new circlips so the open end is directed

either down or up.

B324D

! CAUTION

Incorrect installation of the piston rings will result in
engine damage.

2-14

11. Install the cylinder base gaskets onto the crankcase

making sure each gasket aligns with crankcase

transfer passages.

12. Rotate each piston ring until the ring ends are

properly positioned on each side of the ring

keeper; then apply oil to the piston assemblies and

cylinder bores. Remove the rubber bands from the

connecting rods.

726-306B

„NOTE: Apply a generous amount of oil to the sur-
faces of the pistons, rings, and cylinder bores.

„NOTE: Inspect the cylinder-base gasket to
ensure proper positioning.

13. For each piston, place a piston holder (or suitable

substitute) beneath the piston skirt and square the

piston in respect to the crankcase; then using a ring

compressor or the fingers, compress the rings and

slide the cylinder over the piston. Remove the pis-

ton holder and seat the cylinder firmly onto the

crankcase.

A828A

14. Place each cylinder head with dowel pins and gas-

ket into position and install the eight nuts. DO

NOT TIGHTEN AT THIS TIME.

15. Temporarily install the exhaust manifold and

secure with four nuts and lock washers to square

the cylinders. Tighten the manifold nuts until

snug.

16. With the exhaust manifold in place, tighten the

cylinder head nuts (from step 14) in three steps to

17 ft-lb using the pattern shown.

0725-318

17. In order, install the gear, shim, gasket, retainer,

gasket, and oil-injection pump. Secure with two

screws, lock washers, and washers. Tighten to 8 ft-

lb.

AB078

„NOTE: If removed, secure the ignition coil to the
fan case.

18. Align the reference marks made during disassem-

bly; then tighten the stator plate with two Allen-

head cap screws (coated with red Loctite #271),

lock washers, and washers tightened to 8 ft-lb.

„NOTE: Before installing the flywheel, wipe the
crankshaft and flywheel taper clean using a clean
cloth.

19. Install the key in the crankshaft and slide the fly-

wheel onto the crankshaft making sure the key-

ways match.

! CAUTION

Make sure circlips are firmly seated and the open
end is directed either down or up before continuing
with assembly.

! CAUTION

Be sure the gear is properly aligned with the slot of
the oil-injection pump shaft. The injection pump will
be damaged if these two components are not aligned.

2-15

2

20. Place the fan case into position and secure with

four nuts. Tighten the nuts to 15 ft-lb.

A814

21. In the following order, install a gasket (one on

each port), shroud, gasket (one on each port), insu-

lator, gasket (one on each port), and intake mani-

fold. 

22. Secure with nuts (threads coated with red Loctite

#271). Tighten nuts in three steps to 9 ft-lb.

23. Place the intake flange into position and secure

with nuts (threads coated with red Loctite #271),

lock washers, and washers. Tighten to 9 ft-lb.

24. Remove the exhaust manifold.

25. Install spark plugs and tighten to 19 ft-lb.

26. Attach the oil-injection hoses to their fittings.

Secure with clamps; then test the engine for air

leaks (see Section 3).

27. Temporarily secure the starter pulley on the fly-

wheel with three cap screws. Install the flywheel

washer, lock washer, and nut. Apply red Loctite

#271 to the crankshaft threads before installing the

flywheel nut. Using a spanner wrench to secure the

crankshaft, tighten the flywheel nut to 58 ft-lb.

MD2499

28. Remove the starter pulley. Position the fan belt

drive pulley into the belt. Align the starter pulley

holes with those in the belt pulley. Start one of the

cap screws into the flywheel; then rotate the belt

pulley and starter pulley in a counterclockwise

direction.

29. When the pulley pivots on the cap screw, rock the

pulleys backward or forward until the remaining

cap screw holes align. Install the remaining two

cap screws and tighten evenly to 10 ft-lb.

„NOTE: Apply red Loctite #271 to the threads of
the cap screws before installing.

MD2500

30. Place an exhaust manifold gasket on each exhaust

port making sure the metal side of the gasket faces

the cylinder. Slide the exhaust-side cooling shroud

onto the exhaust port studs; then place the upper

cooling shroud into position and secure the

shrouds with cap screws noting the location of the

longer cap screws from disassembling. Tighten to

60 in.-lb. Connect the spark-plug caps.

31. Place a gasket on each exhaust port making sure

the metal side of each gasket faces away from the

cylinder. Install the exhaust manifold, lock wash-

ers, and nuts and tighten to 15 ft-lb.

Installing Engine

1. Place each engine mounting bracket onto the

engine. Secure with cap screws (coated with blue

Loctite #243), washers, and lock washers. Tighten

to 25 ft-lb.

2. Place the engine assembly into position in the

engine compartment. Secure the engine to the

front end with the cap screws, washers, and lock

nuts. Tighten to 25 ft-lb.

2-16

370-ENG07A

„NOTE: If equipped with electric start, place the
starter motor bracket on the crankcase and install
the front two and lower rear cap screws, lock wash-
ers, and washers. Place the starter motor into posi-
tion and secure with two washers and lock nuts.
Tighten securely.

3. Connect the oil-supply hoses to the oil-injection

pump.

4. Connect the oil-injection cable to the oil-injection

pump control arm and secure the cable mounting

pin with a nylon washer and E-clip.

5. Place the carburetor into position making sure the

boot is properly positioned and secure with the

flange clamp.

AH283D

„NOTE: At this point, bleed the oil-injection sys-
tem and check synchronization (see Section 4).

6. Connect the impulse hose to the crankcase, the

main wiring harness, the CDI unit wiring harness,

and the spark plug caps.

7. Place the recoil starter into position and secure

with four cap screws and lock washers. Tighten to

8 ft-lb.

„NOTE: If equipped with electric start, secure the
battery ground cable with the rear cap screw.

AB073

8. Place the expansion chamber and grafoil gasket

into position and secure with springs.

AB105D

9. Place the engine mount shims into position

between the torque bumper and engine mounting

bracket; then tighten the torque bumper jam nut.

10. Place the drive clutch into position on the crank-

shaft; then install the lock washer and bolt.

Tighten the clutch bolt to 55 ft-lb.

CM016

„NOTE: Before installing the drive clutch, be sure
to wipe both the crankshaft taper and clutch
mounting taper clean using a clean towel.

! CAUTION

When installing the carburetor, make sure the
gasline hose is properly routed to avoid premature
wear and/or contact with exhaust components.