Connecting Rod And Piston Replacement - GMC G Service Manual

I ? | Important
• Line up the timing marks on the camshaft
sprocket and crankshaft sprocket (figure 26).
6. Camshaft sprocket bolts.
Tighten
• Bolts to 28 N*m (21 ft. lbs.).
7. Front cover. Refer to "Front Cover Replacement" in
this section.
8. Water pump.
9. Torsional damper. Refer to "Torsional Damper and
Front Crankshaft Seal Replacement" in this section.
10. Front cover. Refer to "Front Cover Replacement" in
this section.
11. Upper fan shroud.
12. Hood release cable.
13. Radiator. Refer to RADIATOR (SEC. 6B2).
14. Upper fan shroud bolts.
15. Outside air ducts.
16. Hydraulic lifters and pushrods. Refer to "Hydraulic
Lifter Replacement" and "Rocker Arm and Pushrod
Replacement" in this section.
P ^ l Adjust
• Valves. Refer to "Valve Adjustment" in this
section.
17. Rocker arm covers. Refer to "Rocker Arm Cover
Replacement" in this section.
18. Intake manifold. Refer to "Intake Manifold Replace­
ment" in this section.
19. Negative battery cable.
CONNECTING ROD AND PISTON
REPLACEMENT
H
Remove or Disconnect (Figure 29)
Tool Required:
J 5239 Guide Set
1. Cylinder head. Refer to "Cylinder Head Replacement"
in this section.
2. Oil pan. Refer to "Oil Pan Replacement" in this
section.
3. Oil pump (if necessary). Refer to "Oil Pump Replace­
ment" in this section.
4. Ridge or deposits from the upper end of the cylinder
bores.
• Turn the crankshaft until the piston is at BDC.
• Place a cloth on top of the piston.
• Perform the cutting operation with a ridge
reamer.
• Turn the crankshaft until the piston is at TDC.
• Remove the cloth and cuttings.
5. Connecting rod cap. Check the connecting rod and
cap for identification marks. Mark the parts if required.
4.3 LITER V6 6A3-21
The connecting rod and cap must be kept together as
mating parts.
6. Connecting rod and piston.
• Attach J 5239 to the connecting rod bolts
(figure 29).
• Use the long guide rod of J 5239 to push the
connecting rod and piston out of the bore.
7. Connecting rod bearing.
Cleaning, Inspection, And Repair
Clean, inspect and repair or replace the components as
necessary. Measure connecting rod bearing clearance, pis­
ton clearance, ring clearances, etc. Refer to the proper Unit
Repair Manual.
The Unit Repair Manual contains information on:
• Connecting rod and piston.
• Piston rings.
• Connecting rod and crankpin.
• Cylinder bores.
Figure 29 — Replacing the Connecting Rod and
Piston (Typical)
B Install or Connect (Figures 29 through 32)
Tools Required:
J 5239 Connecting Rod Guide Set
J 8037 Ring Compressor
• Make sure the cylinder walls are clean. Lubricate the
cylinder wall lightly with engine oil.
• Make sure the piston is installed in the matching
cylinder.
1. Connecting rod bearings.
• Be certain that the bearing inserts are of the
proper size.
• Install the bearing inserts in the connecting rod
and connecting rod cap.
• Lubricate the bearings with engine oil.