Intake Manifold Replacement - GMC G Service Manual

6A3-8 4.3 LITER V6

INTAKE MANIFOLD REPLACEMENT

M Remove or Disconnect
1. Negative battery cable.
2. Engine cover.
3. Air cleaner and heat stove tube.
• Drain the cooling system.
4. Distributor. Refer to ENGINE ELECTRICAL
(SEC. 6D).
5. Accelerator, cruise control and TVS cables and
bracket.
6. Cruise control transducer (if equipped).
7. Air conditioning compressor; set aside.
8. Generator bracket at the manifold.
9. Idler pulley bracket at the manifold.
10. Fuel and vacuum lines and electrical connections at
the TBI unit and manifold.
11. Heater pipe.
12. Upper radiator hose.
13. Power brake vacuum pipe.
14. Coil wires.
15. EGR vacuum line.
16. Sensors with bracket on right side.
17. Wiring harness on right side; move out of the way.
18. Transmission dipstick tube (if equipped).
19. Intake manifold bolts.
20. Intake manifold and gaskets.
• Old gasket and RTV from the block, heads, and
intake manifold. Remove all RTV that is loose or will
cause interference at assembly.
• Excessive carbon deposits from the exhaust and
EGR passages.
• Excessive scale and deposits from the coolant
passages.
I P I Inspect
• Manifold for cracks and gasket surface damage.
H Install or Connect (Figures
1. Gaskets to the cylinder head. (Port blocking plate to
the rear).
2. RTV to the front and rear sealing surfaces on the
block (figure 8). Apply a 5 mm (3/16-inch) bead of
RTV (part number 1052366 or equivalent) to the front
and rear of the block as shown. Extend the bead 13
mm (1/2-inch) up each cylinder head to seal and
retain the gaskets.
3. Intake manifold to the engine.
4. Intake manifold bolts.
Tighten
• Intake manifold bolts to 48 N*m (35 ft. lbs.). Use
the tightening sequence shown in figure 9.
5. Transmission dipstick tube (if equipped).
6. Wiring harness.
7. Sensors with bracket.
8. EGR vacuum line.
9. Coil wires.
10. Power brake vacuum pipe.
11. Upper radiator hose.
12. Heater pipe.
13. Fuel and vacuum lines and electrical connections at
the TBI and manifold.
14. Idler pulley bracket.
15. Generator bracket.
16. Air conditioning compressor.
17. Cruise control transducer (if equipped).
18. Accelerator, cruise control and TVS cables and
bracket.
19. Distributor. Refer to ENGINE ELECTRICAL
(SEC. 6D).
20. Air cleaner and heat stove tube.
21. Engine cover.
22. Negative battery cableT
• Fill the cooling system with the proper coolant. Refer
to MAINTENANCE AND LUBRICATION (SEC. 0B).
8 and 9)