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How to Replace Intake Manifold Gaskets on a 3.4 Chevy

by Carl Pruit

The Chevy 3.4 liter engine has had a history of developing leaks in the intake manifold gaskets, causing coolant to mix with the engine oil. If this occurs in your vehicle, replace the gaskets right away to prevent any further damage to the engine.

Step 1

Disconnect the negative battery cable in your Chevy 3.4 liter vehicle with a crescent wrench, and move the cable out of the way, being careful not to touch any metal parts.

Step 2

Remove the radiator cap and locate the drain plug on the bottom of the radiator.

Step 3

Slide a drain pan underneath the drain valve, then open the valve with an open end wrench and allow the coolant to drain out.

Step 4

Find the 3 bolts that hold the power steering pump onto the motor, and remove the bolts with a socket wrench.

Step 5

Detach the power steering pump from the engine block and set it aside while leaving the power steering hose attached to the pump. Remove the serpentine belt from around the pump pulley.

Step 6

Take the serpentine belt off the alternator and remove the bolts from the alternator with a socket wrench.

Step 7

Disconnect the electrical connector from the alternator with a socket wrench and remove the alternator from the engine block.

Step 8

Locate the coolant tube on the passenger side of the engine and remove the hoses that feed into the tube, using a pair of needle nose pliers.

Step 9

Detach the coolant tube from the top of the engine using a socket wrench to unfasten the bolts holding it in place.

Step 10

Move the wiring harnesses and vacuum hoses away from the top of the upper manifold plenum while leaving them attached, in order to gain access to the bolts that are holding the plenum in place.

Step 11

Remove the upper manifold plenum from the top of the engine block, using a socket wrench to detach the bolts.

Step 12

Locate the lower coolant tube and fuel lines on the driver's side of the engine and detach from the engine block, using a socket wrench to remove the 13mm nuts.

Step 13

Remove the two intake manifold valve covers using a socket wrench to undo the bolts, and lift the covers away from the engine.

Step 14

Remove any remaining gasket material from the valve covers and the engine block with a putty knife, so that you have a smooth surface when you're ready to attach the new gasket.

Step 15

Place a bead of gasket seal around the inside lip of both intake manifold valve covers, and lay the new gaskets out on the lip of the valve covers over the gasket seal.

Step 16

Place a bead of gasket seal around the lip of the engine block where you will attach the valve covers, and put the covers back on the engine block, using a torque wrench. Tighten the vertical bolts first, then the diagonal bolts in stages until you reach 115 inch-pounds.

Step 17

Reattach the lower coolant line and fuel lines with a socket wrench, and set the upper manifold plenum back on the engine block and secure it with a socket wrench.

Step 18

Connect the upper coolant tube to the engine, using a socket wrench, and put the hoses back onto the coolant tube with the needle nose pliers.

Step 19

Place the serpentine belt around the pulley of the power steering pump and attach the pump to the engine block, fastening the bolts with a socket wrench.

Step 20

Connect the alternator to the engine block with the bolts, leaving the bolts loose so you can adjust the alternator belt.

Step 21

Place the serpentine belt around the alternator pulley and pull back on the alternator with a crowbar, tightening the belt. Secure the bolts with a socket wrench while you keep tension on the belt.

Step 22

Fill the radiator with coolant and put the radiator cap back on top of the tank.

Remove the drain pan from underneath the Chevy and dispose of the drained coolant at an auto supply shop or recycling center.

Warning

  • To avoid burn injuries, allow the Chevy's engine to cool down before attempting to replace the intake manifold gaskets.

Items you will need

  • Crescent wrench
  • Drain pan
  • Open end wrench
  • Metric socket set
  • Needle nose pliers
  • Putty knife
  • Gasket seal
  • 2 new intake manifold gaskets
  • Torque wrench
  • Crowbar
  • Coolant

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