Intake manifold gasket replacement? radiator has a

indicates blown head gasket
do a compression test to confirm then replace head gaskets and have the head/s shaved as they will be warped

Have you replaced the intake manifold gaskets? These engines have a history of leaking intake manifold gaskets. Water leaks into the intake and is burned off in the cylinders. If the engine overheats enough times, you will eventually blow the head gaskets.

Start by performing a compression check to make sure you haven't blown the head gaskets. Then make sure the car is really overheating (i.e. check the temperature of the engine with a infrared thermometer (they are cheap at Harbor Freight).

If it is really overheating, and you've really changed everything else, you need to change the intake manifold gaskets. Be sure to get the improved gaskets from the parts store (they have a metal core with rubber coating).

Remove the 12 bolts that hold the intake to the lower section and disconnect all the hoses and linkages. Replace the lower gaskets and torque the manifold in a radiating sequence in this order.
stages to tighten
stage 1 - 59 inch pounds
stage 2 - 66 inch pounds
stage 3 - 90 degrees

Instructions

1. Removal

Unscrew the bolt that holds the negative connection to the Impala's battery. Set this bolt aside for later use.

Remove the engine cover to access the intake manifold and manifold gasket. Disconnect the throttle body inlet duct from the engine.

Twist off the radiator cap to allow draining of the coolant to flow more smoothly. Place an empty container beneath the radiator's drain plug, and remove this plug. Allow all of the engine coolant to drain into the empty container. Replace the drain plug once you are finished.

Tag all of the electrical wiring and hoses before removing so that reconnection is precise to factory settings. Remove these parts, individually, from the intake manifold.

Loosen the bolts that hold the intake manifold to the Impala's engine block. Lift the intake manifold from the block once all bolts have been completely removed.

Use the flat-head screwdriver to pry the old intake manifold gasket from the engine block. Discard this part once you have removed it.

Clean the engine block thoroughly with the engine degreaser and linen cloth. If necessary, use a gasket scraper to remove excess buildup and grime.

2. Installation

• Coat the top and bottom of the new intake manifold gasket with a chemical sealer so that it bonds to the engine block securely. Position this new manifold gasket so that it lines up perfectly with the cylinder ports of the Impala's engine block.

Place the old intake manifold on top of the newly-installed manifold gasket until it aligns with all of the holes of the cylinder flanges and manifold gasket.

Attach all of the bolts with your hand to the manifold. Once all bolts have been positioned, use a torque wrench and apply 15 foot-pounds of pressure to the bolts to secure the manifold into place.

Reconnect all of the necessary hoses and electrical wiring to the intake. Pour the engine coolant back into the radiator.

Reattach the engine cover on top of the intake manifold and engine block. Start the Impala's engine and check for any leaks around the new intake manifold gasket.

Hi
Check your oil fill cap on the bottom for any signs of white milky looking oil, pull your dipstick and do the same. If yes, then you most likely have an intake manifold gasket leak, very, very common on these cars. Solution is to replace intake manifold gaskets, and check for signs of cracked intake while apart.

when you're facing the engine its the biggest hose on your left going from the radiator to the intake manifold undo the hose clamp on the hose connected the intake manifold pull the hose off, undo the 2 bolts that hold the thermostat housing on (the part that you just pulled the hose off of) pull the thermostat out it will just be sitting there no wires or bolts holding it down, put new one in same way, scrape thermostat housing clean of excess gasket or gasket sealant aswell as the intake manifold. replace the gasket seal it up with high temp r.t.v sealant (gasket sealer) usually comes in a tube an the color is red. bolt thermostat housing back down connect the radiator house, check anti-freeze level an you're good to go

You can purchase an intake manifold gasket set from a local parts store. It should have the upper and lower intake gaskets contained in it. I see you plan on doing the valve cover gaskets as well. It might be a good idea to replace the plugs and wires at the same time to save some trouble down the road. I would recommend doing the oil change and change the thermostat at the same time as well.

Hi I'm litoshop yes under the manifolds you water seals on the block of the engine when you use a lot of water in your radiator the freeze out plugs rust out and you get these leaks to replace you have to remove the manifold you can use some kind of block sealer but I recommend to replace the seal good luck. if this information has been useful please let us know thank you

just replace the intake gasket not the whole intake manifold

This is basicly a very time consuming job rather than a physically hard one to complete. In order to replace the gasket you must remove the intake plenum,throttle body, and misc. vacuum hoses. The wiring harness connections must also be disconnected. Finally the intake manifold is exposed. The bolts holding the manifold to the block are removed exposing the leaking gasket. After removing the push rods and placing them in the correct order to be replaced the gasket and sealants can be removed. Finally replace everything in reverse order. Be sure to consult a GM manual for correct bolt torch specs. The correct specs for the manifold bolts usually come with the gasket. Make sure to change your oil a few times after this job in case any coolant entered the block. Also,change the thermostat and the oil seal on the distributor half shaft cap while you have everything off. Good Luck