Thermostat Housing Installation; Intake Manifold Installation; Exhaust Manifold Installation; Flywheel Installation - GMC 1990 Light Truck Repair Manual

6A1-30 2.5 LITER L4 ENGINE
110. Bolt
111. Coolant Pump
112. Gasket
Figure 57—Water Pump Components
5. Fan and fan clutch.
THERMOSTAT HOUSING
INSTALLATION
0
Install or Connect (Figure 58)
1. Thermostat housing and new gasket.
2. Thermostat housing bolts.
3. Thermostat bypass hose.
8 Stud
.
9.
Bolt
10
Coolant F itting
.
Gasket
11 .
12
Therm ostat
.
13.
Therm ostat Housing
14.
Bolt
15.
Hose Clamp
16. Hose
Gasket
21 .
Figure 58—Thermostat Housing Components

INTAKE MANIFOLD INSTALLATION

110
F-01987
|~K~| Install or Connect (Figure 60)
filter, generator, etc.) as directed in the proper Truck
Service Manual. Connect all vacuum hoses and electrical
equipment the same way as removed.
14
F-01986
Install or Connect (Figure 59)
1. Gasket.
• Apply sealant to the bolts indicated in figure 59.
2. Intake manifold.
3. Intake manifold bolts and washers.
Tighten
• Intake manifold bolts to 34 N m (25 ft. lbs.).
4. Vacuum lines and electrical connectors, as needed.
EXHAUST MANIFOLD
INSTALLATION
1. Exhaust manifold and a new gasket.
2. Exhaust manifold bolts and washers.
Tighten
• Exhaust manifold bolts. Use the tightening
sequence and the specifications shown in
figure 60.
3. Oxygen sensor wire.
4. Thermae heat stove pipe.

FLYWHEEL INSTALLATION

Install or Connect (Figure 5)
1. Spacer (68).
2. Flywheel (67).
3. Bolts (66).
Tighten
• Flywheel bolts (66).
— Automatic transmissions: 75 N m (55 ft.
lbs.).
— Manual transmissions: 90 N m (65 ft.
lbs.).
ENGINE ACCESSORY
INSTALLATION
Install the engine accessories (distributor, TBI unit oil
ENGINE SETUP AND
TESTING
1. After overhaul, the engine should be tested before
installing it in the vehicle. If a suitable test stand is
not available, the following procedure can be used
after the engine is installed in the vehicle.