Changing the valve guides

• Calculate the clearance between valve guides and valve stems and check that it is within the specified limits; if not, change any worn parts.

Changing the valve guides

1. Using puller tool no. 1.821.005.000 (A.3.0134), remove the worn valve guides.

• Check that the outside diameters of the valve guides and their seats on the cylinder heads are within the specified limits and meet the assembly interference.

1. Insert the new valve guides in their seats using the tools illustrated.

• Ream the inside diameter of the valve guides to calibrate the holes to the specified diameter.

Checking the valve springs

• Check that the "free" length of the valve springs is within the specified limits.

NOTA: The resting planes must be parallel with one another and perpendicular to the axis of the spring with a maximum error of 2°.

1. Using a torque meter, check that the characteristic data of the springs are within the specified limits.