GMC T Series 1994 Repair Manual page 545

Inspect
• Flywheel for burning, scoring, warping, and wear.
Replace the flywheel if necessary. Do not machine
the flywheel.
• Flywheel ring gear for worn or broken teeth.
Flywheel Ring Gear Replacement
1. Use a torch to heat the gear around the entire
circumference, then drive the gear off the flywheel,
using care not to damage the flywheel.
N O T IC E : N e v e r h e a t s t a r t e r g e a r to r e d h e a t
a s t h is w ill c h a n g e m e t a l s t r u c t u r e .
O IL FILTER AND OIL COOLER
BYPASS VALVE
REPLACEMENT
Install or Connect (Figure 61)
1. Oil filter bypass valve. Tap into place, using a
16-mm socket.
2. Oil cooler bypass valve by pressing into place and
retaining with cup plug.
3. Oil filter.
CAMSHAFT INSTALLATION
Install or Connect (Figures 1 and 62)
• When a new camshaft is installed, replacement of
all hydraulic lifters, engine oil, and oil filter is rec­
ommended.
1. Key (92).
2. Spacer (93), with the ID chamfer towards the cam­
shaft.
3. Camshaft (95) (figure 1).
• Coat the camshaft lobes with " Molykote" or
equivalent.
• Lubricate the camshaft bearing journals with
engine oil.
• Insert the camshaft carefully into the block to
avoid damage to the camshaft bearings.
N O T IC E : R e f e r to "N o t i c e " o n p a g e 6 A 7 -1 .
4. Thrust plate (91) and bolts (86).
^ Tighten
• Bolts (86) to 23 N.m (17 lbs. ft.).
CRANKSHAFT INSTALLATION
- n - Install or Connect (Figures 63 and 64)
N O T IC E : F o r s t e p s 5, 6, a n d 7 r e f e r to "N o ­
t i c e " o n p a g e 6 A 7 -1 .
2. Uniformly heat the flywheel gear to temperature
which will expand the gear to permit installation.
Temperature must not exceed 200° C (400° F).
3. As soon as the gear has been heated, install on
the flywheel.
TORSIONAL DAMPER
Inspect
• Oil seal contact area on the torsional damper shaft
for grooving and roughness. Replace if necessary.
• Always replace torsional dam per if crankshaft
breakage occurs.
ASSEMBLY
2. Crankshaft.
3. Lower main bearing inserts to the main bearing
caps.
W
/
INSTALLATION
F2474