Snowmobile Yamaha FX10X, FX10RTX, FX10RTRX, FX10RTRAX, FX10MTX, FX10MTRX, FX10MTRAX. Manual - part 50

5-20

ENG

CAMSHAFTS

6. Inspect:

• Camshaft sprocket

More than 1/4 tooth 

a wear → Replace the

camshaft sprockets, timing chain, and crank-
shaft as a set.

a 1/4 tooth
b Correct
1 Timing chain roller
2 Camshaft sprocket

7. Inspect:

• Timing chain guide (top side)

Damage/wear 

→ Replace

8. Remove:

• Timing chain tensioner rod 1 
• Timing chain tensioner spring 2 
• Timing chain tensioner housing 4 

NOTE:

Squeeze the timing chain tensioner clip 3, and
then remove the timing chain tensioner rod and tim-
ing chain tensioner spring.

9. Inspect:

• Timing chain tensioner housing
• Timing chain tensioner rod
• Timing chain tensioner spring

Damage/wear 

→ Replace the as a set.

10. Assemble:

• Timing chain tensioner spring
• Timing chain tensioner rod

NOTE:

Prior to installing the timing chain tensioner rod,
drain the engine oil from the timing chain tensioner
housing.

1

2

3

4

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CAMSHAFTS

Assembly steps:

• Install the timing chain tensioner spring and tim-

ing chain tensioner rod 1.

• Squeeze the timing chain tensioner clip 2, and

then push the timing chain tensioner rod 3 into
the timing chain tensioner housing.

NOTE:

Do not release the timing chain tensioner clip while
pushing the rod into the housing, otherwise the rod
may be ejected.

• Hook the clip 4 to the timing chain tensioner

rod 3.

NOTE:

Hook the timing chain tensioner rod pin 5 to the
center of the clip 4. After the installation, check
that the clip 4 can come off by its own weight by
pushing the timing chain tensioner rod 3 at the
position of installation.

1

3

5

4

11. Inspect:

• All parts

Damage/wear 

→ Replace the defective 

part(-s).

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ENG

CAMSHAFTS

INSTALLATION

1. Install:

• Intake camshaft sprocket 1 
• Exhaust camshaft sprocket 2 

(with the special tool 3)

• Camshaft sprocket bolts

NOTE:

Make sure that the holes 

a in the cylinder #3 cam

and marks 

b on the camshaft sprockets are in the

position shown in the illustration.
c: Cylinder #3 - cam

Rotor holding tool:

90890-01235

Universal magneto & rotor holder:

YU-01235

T

 

R

.

.

Camshaft sprocket bolt:

24 Nm (2.4 m · kg, 17 ft · lb)

EX

IN

2

1

b

c

a

b

a

b

c

2. Install: 

• Intake camshaft 1 

(with the camshaft sprocket)

• Exhaust camshaft 2 

(with the camshaft sprocket)

Installation steps:

• Turn the crankshaft clockwise.
• When piston #3 is at TDC on the compression

stroke, align the “I” mark 

a on the AC magneto

rotor with the stationary pointer 

b on the AC

magneto cover.

• Install the timing chain onto both camshaft

sprockets, and then install the camshafts.

NOTE:

• Install the camshafts with the hole 

c in the cylin-

der #3 - cam facing up. 

• When installing the timing chain, start with the

intake camshaft and be sure to keep the timing
chain as tight as possible on the intake side. 

• Make sure the marks 

d on the timing chain

sprockets are parallel with the edge of the cylin-
der head. 

e: Cylinder #3 - cam

b

a

1

c

2

EX

IN

d

e

d

e

d

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CAMSHAFTS

3. Install:

• Dowel pins
• Intake camshaft caps
• Exhaust camshaft caps

NOTE:

• The  “I” mark refers to the intake camshaft caps

and the “E” mark refers to the exhaust camshaft
caps. 

• Install the camshaft caps with the arrow mark 

a

pointing towards the right side of the engine.

• Make sure the holes 

b in the camshaft are

aligned with the arrow mark 

a on the camshaft

caps. 

4. Install:

• Camshaft cap bolts

NOTE:

Tighten the camshaft cap bolts in stages and in a
crisscross pattern, working from the inner caps out. 

CAUTION:

• Lubricate the camshaft cap bolts with the

engine oil.

• The camshaft cap bolts must be tightened

evenly or damage to the cylinder head, cam-
shaft caps, and camshafts will result. 

• Do not turn the crankshaft when installing the

camshaft to avoid damage or improper valve
timing. 

T

 

R

.

.

Camshaft cap bolt:

10 Nm (1.0 m · kg, 7.2 ft · lb)

a

b

a

b