Subaru EA190V, Service Manual

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40
Correct
Incorrect
Reamer
：
For best results, be sure the cylinder head is at room temperature
before reaming valve guides.
Coat the reamer and valve guide with cutting oil. Rotate the reamer
clockwise through the valve guide for the full length of the reamer.
Continue to rotate the reamer clockwise while removing it from the
valve guide.
Tools
：
Valve guide reamer
a) Thoroughly clean the cylinder head to remove any
cutting residue.
b) Check the valve guide bore, it should be straight, round
and centered in the valve guide, insert the valve and
check operation. If the valve does not operate smoothly,
the guide may have been bent during installation.
Replace the valve guide if it is bent or damaged.
c) Check the valve stem-to-guide clearance
d) The valve stem-to-guide clearance
：
The vale guide bore
detract the valve stem outside diameter to get the
clearance between the valve guide and valve stem.
e) If the clearance is over the service limit, judge a new guide if it can make the clearance conforming to
service limit, if conforming to, replace the guide and ream the guide, refinish the valve when
replacing the valve guide.
(4) Valve seat
：
a) Thoroughly clean the combustion chambers and
valve seats to remove carbon deposits.
Apply a light coat of red lead powder or
erasable color painting to the valve faces.
b) Insert the valves, and then press the valve
several times forcefully. Be sure not to rotate
valve on the seat.
Valve seat painted the color will show contacted with the valve. If not, the transferred marking
compound will show any area of the seat that is not concentric.
c) Using 45°cutter, remove enough material to produce a smooth and concentric seat. Turn cutter
clockwise, never counterclockwise.
Valve guide
reamer
Valve face