Page 220
REPAIR INSTRUCTIONS, PART 1
227
Figure 227 — Camshaft Gear Removal
INSPECTION
Refer to Figure 228.
1. Thoroughly clean the camshaft.
Use the magnaflux (PT7190) inspection
procedure to detect cracks.
2. Inspect the camshaft lobes and journals for
evidence of cracks, pitting, scoring or severe
wear. If any of these conditions exist,
replace the camshaft.
3. Inspect the camshaft gear and captured
thrust washer for cracks, pitting, scoring or
adverse wear.
4. Visually inspect the key for signs of
distortion or breakage.
CAMSHAFT GEAR INSTALLATION
The camshaft gear is shrink-fitted to the
camshaft. To install the gear, it must be heated in
an oven to 425°F (204°C). DO NOT attempt to
heat the gear with a welding torch as this method
will not provide even heating and could cause
weakening of the metal.
An oven is the preferred method for heating the
camshaft gear. However, an industrial grade hot
plate can be used as an alternative to the oven.
When using a hot plate, temperature sticks or a
thermocouple must be used to determine gear
temperature. The hot plate, temperature sticks
and thermocouple are available through any
industrial supply company.
The camshaft gear is a “long-life” part that should
be reused providing it is not damaged.
When installing the camshaft gear, use only the
heat method procedure below for both new or
used parts. DO NOT use a press to install the
gear.
HEAT METHOD — CAMSHAFT GEAR
INSTALLATION
Refer to Figure 228.
1. Using a suitable contact-type cleaner that
dries rapidly and leaves no residue,
thoroughly clean the camshaft and the gear.
The camshaft and gear must be grease- and
oil-free to ensure a good shrink-fit.
2. Install the key into the camshaft keyway. It
may be necessary to tap the key with a soft
metal hammer to ensure proper seating of
the key. The original key should be reused if
it not damaged. If the key is slightly loose in
the key slot, it may move when the cam gear
is being installed. To avoid this use a
hammer to make two or three small dings
along the top edges of the slot before
installing the key. When the key is installed,
the dings will help hold the key in place
when the gear is being installed.
5-111.bk Page 220 Monday, July 10, 2006 2:26 PM
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