When Timing Chain Assembly Is Removed

NOTE: Inspection of cam clearance should be performed while engine is cold.

When inspecting #1 and #3 cylinders

Remove the rocker cover RH. Ref. to MECHANICAL) (H4DOTC)>Rocker Cover>INSTALLATION>ROCKER COVER RH .
NOTE: When working on the vehicle, place a suitable container under the vehicle.

Check the #1 and #3 cylinder cam clearance.

CAUTION: Intake and exhaust camshafts can be independently rotated with the timing chain removed. When the intake valve and exhaust valve lift at the same time, the valve heads contact each other and valve stem may bend. Do not turn it to the outside of range of zero lift (cam base circle position) (in range where it can be turned lightly by hand).

NOTE:

For cam clearance inspection, adjust the cam base circle position so that the thickness gauge (A) can be inserted easily by hand turning the camshaft (cam sprocket) to be measured.
Measure the roller surface of cam base circle and roller rocker arm using thickness gauge (A).
If the measured value is out of standard, take notes of the value in order to adjust the cam clearance later on.

Cam clearance:

Intake

Standard

0.13+^0.02 -0.03 mm (0.0051+^0.0008 -0.0012 in)

Exhaust

Standard

0.22±0.02 mm (0.0087±0.0008 in)

Courtesy of SUBARU OF AMERICA, INC.

When inspecting #2 and #4 cylinders

Remove the rocker cover LH. Ref. to MECHANICAL (H4DOTC)>Rocker Cover>REMOVAL>ROCKER COVER LH .
NOTE: When working on the vehicle, place a suitable container under the vehicle.

Check the #2 and #4 cylinder cam clearance.

NOTE:

Because the intake camshaft is pressurized by the high-pressure fuel pump, it is almost impossible to turn the intake camshaft lightly by hand. Since the zero-lift position is adjusted at the removal of the timing chain LH, measure the cam clearance at that position.
For cam clearance inspection on exhaust side, adjust the cam base circle position so that the thickness gauge (A) can be inserted easily by hand turning the exhaust camshaft (cam sprocket).
Measure the roller surface of cam base circle and roller rocker arm using thickness gauge (A).
If the measured value is out of standard, take notes of the value in order to adjust the cam clearance later on.

Cam clearance:

Intake

Standard

0.13^+0.02 -0.03 mm (0.0051^+0.0008 -0.0012 in)

Exhaust

Standard

0.22±0.02 mm (0.0087±0.0008 in)

Courtesy of SUBARU OF AMERICA, INC.

If necessary, adjust the cam clearance. Ref. to MECHANICAL (H4DOTC)>Cam Clearance>ADJUSTMENT .
After inspection, install the related parts in the reverse order of removal.