Valve Stem Oil Deflector Replacement; Valve Stem-To-Guide Clearance; Valve Guides - Jeep 1979 CJ-5 Technical & Service Manual

1B-6
ENGINES
1/32-INCH
( 0 . 7 8 7 mm)
V A L V E M A R G I N
CORRECT V A L V E FACING
NO M A R G I N
INCORRECT V A L V E FACING
6 0 1 1 7
Fig. 1B-8 Valve Refacing
Use tapered stones to obtain the specified seat widths
when required.
Control seat runout to a maximum of 0.0025 (0.064
mm) inch (fig. 1B-9).
Fig. 1B-9 Checking Valve Seat Runout
Valve Stem Oil Deflector Replacement
Nylon valve stem oil deflectors are installed on each
valve stem to prevent rocker arm lubricating oil from
entering the combustion chamber through the valve
guides. Replace the oil deflectors whenever valve service
is performed or if the deflectors have deteriorated.
Valve stem oil deflector replacement requires removal
of valve spring(s). Refer to Valve Springs for procedure.
Valve Glides
The valve guides are an integral part of the cylinder
head and are not replaceable. When the stem-to-guide
clearance is excessive, ream the valve guides to accom-
odate the next larger oversize valve. Oversize service
valves are available in 0.003-inch (0.076 mm), 0.015-inch
(0.381 mm), and 0.030-inch (0.762 mm) sizes.
Valve Guide Reamer Sizes
Reamer
Size
Tool Number
Size
> J-6042-1 0.003-inch
J-6042-5 0.015-inch
J-6042-4
0.030-inch
6 0 2 6 0
N O T E : Ream valve guides in steps, starting with the
0.003-inch (0.076 mm) oversize reamer and progressing
to the size required.
Valve Stem-to-Gulde Clearance
Valve stem-to-guide clearance may be checked by ei-
ther of the following two methods.
Preferred Method:'
(1) Remove valve from head and clean valve guide
with solvent and bristle brush.
(2) Insert telescoping gauge into valve guide ap-
proximately 3/8-inch (9.525 mm) from valve spring side
of head (fig. 1B-10) with contacts crosswise to cylinder
head. Measure telescoping gauge with micrometer.
(3) Repeat measurement with contacts lengthwise
to cylinder head.
(4) Compare crosswise to lengthwise readings to de-
termine out-of-roundness. If measurements differ by
more than 0.0025-inch (0.064 mm), ream guide to accom-
odate oversize valve.
(5) Compare valve guide diameter with diameter
listed in Specifications. If measurement differs more
than 0.003-inch (0.076 mm), ream guide to accomodate
oversize valve.
GAUGE
Fig. 1 B - 1 0 Valve Stem-io-Guide Clearance Measurement with
Telescoping Gauge