Cylinder Head & Valve Train


Valve Guides
Valve Movement
Measure the guide-to-stem clearance with a dial indica-
tor while rocking the stem in the direction of normal thrust
(wobble method).
Intake Vaive Stem-to-Guide Clearance:
Standard (New): 0.05—0.11 mm
(0.002-0.004 in)
Service Limit: 0.16 mm (0.006 in)
Exhaust Valve Stem-to-Guide Clearance:
Standard (New): 0.10—0.16 mm
(0.004-0.006 in)
Service Limit: 0.22 mm (0.009 in)
Valve extended 10 mm out from seat.
If measurement exceeds the service limit, recheck
using a new valve.
If measurement is now within the service limit,
reassemble using a new valve.
If measurement still exceeds limit, recheck using
alternate method below, then replace valve and
guide, if necessary.
NOTE: An alternate method of checking guide to
stem clearance is to subtract the O.D. of the valve
stem, measured with a micrometer, from the I.D. of
the valve guide, measured with an inside
micrometer or ball gauge.
Take the measurements in three places along the
valve stem and three places inside the valve guide.
The difference between the largest guide measure-
ment and the smallest stem measurement should
not exceed the service limit.
Intake Valve Stem-to-Guide Clearance:
Standard (New): 0.025 — 0.055 mm
(0.001-0.002 in)
Service Limit: 0.08 mm (0.003 in)
Exhaust Valve Stem-to-Guide Clearance:
Standard (New): 0.05—0.08 mm
(0.002-0.003 in)
Service Limit: 0.11 mm (0.004 in)