Yamaha WR250FM service manual Ca U Ti O N

CAMSHAFTS

ENG

•Fit the timing chain 3 onto both camshaft sprockets and install the camshafts on the cylinder head.

NOTE:

The camshafts should be installed onto the cylinder head so that the punch mark c on the exhaust camshaft and the punch mark d on the intake camshaft must align with the cylinder head surface, as shown in the illustration.

CAUTION:

Do not turn the crankshaft during the camshaft installation. Damage or improper valve timing will result.

•Install the clips, camshaft caps 4 and bolts (camshaft cap) 5.

T .

R .

Bolt (camshaft cap):

10 Nm (1.0 m • kg, 7.2 ft • lb)

NOTE:

•Before removing the clips, cover the cylin- der head with a clean rag to prevent the clips from into the cylinder head cavity.

•Apply the engine oil on the thread and con- tact surface of the bolts (camshaft cap).

•Tighten the bolts (camshaft cap) in a criss- cross pattern.

CAUTION:

The bolts (camshaft cap) must be tight- ened evenly, or damage to the cylinder head, camshaft caps, and camshaft will result.

2.Install:

• Timing chain tensioner

Installation steps:

•While pressing the tensioner rod lightly with fingers, use a thin screwdriver and wind the tensioner rod up fully clockwise.

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