Categories
Cylinder Head & Valve Train

nsxd06044a.pdf

4. Working from the camshaft side, use the driver and
an air hammer to drive the guide about 2 mm
towards the combustion chamber. This will knock
off some of the carbon and make removal easier.
VALVE GUIDE DRIVER
07742–0010100
5. Turn the head over and drive the guide out toward
the camshaft side of head.
If a valve guide still won’t move, drill it out with a
5/16 inch bit, then try again.
CAUTION: Drill guides only in extreme cases: you
could damage the cylinder head if the guide breaks.
6. Remove the new guide(s) from the refrigerator, one
at a time, as you need them.
Do not use a torch; it may warp the head.
Do not get the head hotter than 300 °F (150°C)
excessive heat may loosen the valve seats.
To avoid burns, use heavy gloves when handling
the heated cylinder head.
Valve Guides
Replacement
1. As illustrated in the removal steps of this pro-
cedure, use a commercially—available air-impact
driver attachment modified to fit the diameter of
the valve guides. In most cases, the same pro-
cedure can be done using the Valve Guide Driver
and a conventional hammer.
COMMERCIALLY AVAILABLE
VALVE GUIDE DRIVER
5.3 mm
(0.21 in)
87 mm
(3.43 in.)
57 mm
(2.24 in.) 10.8 mm
(0.42 in)
Removal and Installation
VALVE GUIDE DRIVER
07742–0010100
2. Select the proper replacement guides and chill them
in the freezer section of a refrigerator for about an
hour.
3. Use a hot plate or oven to evenly heat the cylinder
head to 300°F (150°C). Monitor the temperature
with a cooking thermometer.
CAUTION:
Always wear safety goggles or a face shield when
using the air hammer.
Hold the air hammer directly in line with the valve
guide to prevent damaging the driver.
CAUTION:

7. Slip a 6 mm steel washer and the correct driver at-
tachment over the end of the driver (The washer will
absorb some of the impact and extend the life of the
driver).
DRIVER 6 mm WASHER ATTACHMENT
8. Install the new guide(s) from the camshaft side of
the head; drive each one in until the attachment bot-
toms on the head. If you have all twelve guides to
do, you may have to reheat the head one or two
more times.
VALVE GUIDE
DRIVER, 5.5 mm
07742-0010100
Valve Guide Installed Height:
Intake: 13.75-14.25 mm (0.541-0.561 in)
Exhaust: 13.75-14.25 mm (0.541-0.561 in)
Valve Guide Reaming
NOTE: For new valve guides only.
1. Coat both reamer and valve guide with cutting oil.
2. Rotate the reamer clockwise the full length of the
valve guide bore.
3. Continue to rotate the reamer clockwise while
removing it from the bore.
4. Thoroughly wash the guide in detergent and water
to remove any cutting residue.
5. Check clearance with a valve (page 6-43).
REAMER HANDLE VALVE GUIDE
REAMER, 5.5 mm
07HAH-PJ7010A
Turn reamer in
clockwise direction
only.
Verify that the valve slides in the IN, EX valve
guides without exerting pressure.

Attachments