Written by: Mike Ervin
following steps are needed for intake manifold removal and installation.
- Disconnect the negative battery cable.
- Drain the cooling system.
- Remove the air cleaner assembly.
- Remove A.I.R. crossover pipe.
- Either remove the thermostat housing and the hose, or if
the manifold is not being replaced, you may just disconnect the hose. I recommend
changing your thermostat either way.
- Remove alternator upper bracket.
- Disconnect the heater hose and disconnect all electrical
connections and vacuum lines from the manifold. Remove the EGR valve (if equipped).
- On vehicles equipped with power brakes remove the vacuum
line from the vacuum booster to the carburetor.
- Move the air conditioning compressor to one side, if
- Disconnect the fuel line to the carburetor or TBI unit.
- Disconnect the carburetor linkage.
- Disengage the electrical connections at the TBI unit, if
- Remove the carburetor or TBI unit, if necessary.
- Remove the intake manifold bolts. Remove the
manifold and the gaskets.
- Use a tap of the correct size to chase the threads in the
intake bolt holes in the cylinder heads. Mount each bolt in a vise run a die down
the threads to remove corrosion and restore the threads. Dirt, corrosion, sealant,
and damaged threads will affect torque readings.
- The mating surfaces of the intake manifold and the
cylinder heads must be perfectly clean when the intake is installed. I prefer to use
RTV gasket sealant on the front and rear ridges of the block-to-manifold mating
surfaces. Run a solid 3/8-inch bead across and extending up on the head about
1/2-inch. Don't let any of the RTV go into the lifter valley if you can help
it. Run a small bead on the head and the intake around the water jackets if your
gaskets don't have a built-in bead.
- Set the intake straight down in place without as much
lateral movement as possible.
- Coat the threads on the intake bolts with a good sealer,
such as Permatex No.2. This will keep oil from migrating up the threads out of the
lifter valley. Torque the intake manifold bolts to 30-35 ft. lbs. starting in the
center and going in a criss-cross pattern, working your way to the outside. I would
do this in two steps of 20 and then the final 30-35 ft. lbs..
- Reverse the removal procedure to complete
installation. Refer back to the distributor removal and
installation procedure to help you install the distributor.