Pontiac Fiero 1988 Service Manual page 297

6A-20 GENERAL ENGINE MECHANICAL
7. Metering valve
8. Push rod seat
9. Push rod seat retainer
10. Push down on the push rod seat to relieve the
plunger spring pressure and remove the 1.5mm
(1/6") pin.
f Important
Test lifter leak-down rate (refer to
Leak-Down Rate Test).
Flat Tappet: Coat the lifter bottom with
GM P/N 1052367, or equivalent. If new
lifters were installed, add GM P/N 1052367
EP lubricant, or equivalent, to the engine
oil.
Roller Tappet: Dip lifter in GM P/N
1052365, or equivalent.
VALVE LIFTER LEAK-DOWN RATE TEST
(FLAT TAPPET LIFTERS ONLY)
Tool Required:
J 5790 Tester (Figure 45)
1 - START
2 - STOP
3 - WEIGHT
4 -
RAM
5 - ADAPTER
BT 105-2
6— ROTATE RESERVOIR
ONE REVOLUTION
EVERY TWO SECONDS
7 - TOOL BT-60 OR
J-5790-01
G20041-6A
Figure 45 Measuring Valve Lifter Leak-Down Rate
With J 5790-01, test the valve lifter leak-down
rate:
1. Fill tester cup to approximately one inch from top
with the special fluid, which is available from
tester manufacturer.
2. Swing weight arm out of the way, raise ram, and
position lifter into boss in center of tester cup.
3. Adjust ram (with weight arm clear of ram) so that
the point is positioned on the set line (marked
"S"). Tighten jam nut to maintain setting.
4. Operate lifter through full travel of plunger by
pumping weight arm to fill lifter with test fluid
and force out air.
Important
• Lifter must be completely submerged at all
times.
• Continue pumping for several strokes after
definite resistance is felt.
5. Raise weight arm to allow plunger spring to
expand fully; lower arm onto ram and commence
turning crank slowly (1 revolution every 2
seconds).
6. Time indicator travel from lower line (first line
above set line) to line marked .094 or 3/32", while
rotating cup with crank. Lifter is satisfactory if
rate is between 12 and 90 seconds.
CYLINDER BLOCK
4 *
Disassemble
Cooling jacket plugs
Obtain a suitable self-threading screw
Diill a hole into the plug
Install the self-threading screw
Pry out plug
Oil gallery screw plugs
Important
• Some plugs have holes drilled to spray oil on
the timing chain and the distributor gear.
Note the position of these plugs to aid in
re-assembly.
Camshaft bearings
Refer to Camshaft and Camshaft Bearing.
m
Important
< © Caustic cleaning solution destroys the
bearing material. All bearings must be
replaced after cleaning with a caustic
solution. Do not clean bearing material or
aluminum parts with caustic solutions.
Clean
Sealing material from mating surfaces
Boil in caustic solution
Flush with clean water, or steam
Oil passages
All blind holes
Spray or wipe cylinder bores and machined
surfaces with engine oil
Inspect
Deck surface for flatness. Use a straight edge and
a feeler gage (Figure 46). Minor irregularities
may be carefully machined. If more than .25 mm