Timing Gears; Flywheel - Chevrolet CHEVY VAN G10 SERIES Service Manual

Fig. 2 0 L —Checking Camshaft Gear R unout
Removal
1. Remove valve lifters as outlined.
2. Remove crankcase front cover as outlined.
3. Remove grille as outlined in Section 13.
4. Remove fuel pum p as o utlined in Section
5. Align tim ing gear m arks th en remove the tw o cam shaft
th ru st plates screws by w orking through holes in the
cam shaft gear (Fig. 19L).
6
. Remove the cam shaft and gear assembly by pulling it out
through the fro n t o f the block.
N O T E : Support camshaft carefully when removing
so as not to damage camshaft bearings.
Installation
1. Install the cam shaft and gear assembly in the engine
block, being careful n o t to damage cam shaft bearings or
cam shaft.
2. T urn crankshaft and cam shaft so th a t the valve timing
marks on th e gear te eth will line up (Fig. 19L). Push
cam shaft into position. Install cam shaft thrust plate-to-
block screws and to rq u e to specifications.
3. Check cam shaft and crankshaft gear run out w ith a dial
indicator (Fig. 20L). The cam shaft gear run o u t should
n o t exceed .004" and the crankshaft gear run o u t should
not exceed .003" .
4. If gear run o ut is excessive, the gear will have to be
removed an d any burrs cleaned from the shaft or the gear
will have to be replaced.
5. Check the backlash betw een th e tim ing gear te e th w ith a
dial indicator (Fig. 21L). The backlash should be n o t less
than .00 4 " nor m ore th an .0 0 6 " .
6
. Install fuel pum p as o utlined in Section
7. Install grille as outlined in S ection 13.
8
. Install crankcase fro n t cover as outlined.
9. Install valve lifters as outlined.
T IM IN G GEARS
Replacement
6
M.
With cam shaft rem oved, crankshaft gear m ay be removed
using Tool J-8105 (Fig. 22L ). To install crankshaft gear use
Tool J-5590 (Fig. 23L). For cam shaft gear replacem ent, refer
to " Cam shaft Disassem bly" in the Chassis Overhaul Manual.

FLYWHEEL

Removal
1. Remove transm ission an d /o r clutch housing and clutch
from engine.
2. Remove flyw heel retaining bolts and remove flywheel.
Installation
1. Clean the m ating surfaces o f flywheel and crankshaft to
make certain there are no burrs.
6
M.
Fig. 21 L—Checking Tim ing Gear Backlash
Fig. 2 2 L —Rem oving Crankshaft Gear
ENGINE 6-23
C H E V Y V A N SH O P M A N U A L