How to Replace a Lower Intake Manifold Gasket

The lower intake manifold of a vehicle is responsible for the air and fuel mixture that keeps the engine running. Within this manifold, radiator coolant runs in conduits that in turn pass through the engine block to cool the system. There are gaskets separating the engine block from the manifold to keep the fuel and coolant from mixing. This gasket will wear over time, which could result in the mixture of the fuel and coolant and have adverse effects on the performance of your engine. The lower intake manifold gasket should be replaced immediately.

Materials

  • Flat head screwdriver
  • Wrench
  • Gasket sealer
  • New intake manifold gasket
  • Electrical tape
  • Sharpie pen

Step 1: Remove the Distributor

Start by removing the distributor. Do this by disconnecting the sparkplug wires from the distributor cap. Be sure to remember the corresponding wires and where they were plugged. Use the Sharpie pen to label them if necessary. Putting them in the wrong order will have a negative effect on the timing and efficiency of your engine, eventually disabling it. Use the wrench to remove the nut under the distributor. Remove the distributor and lift it out.

Step 2: Remove Radiator and Water Pump Hoses

The manifold will have two hoses attached to its side, the water pump and radiator hose. Clamps are the only things securing them. Again, mark both hoses and their corresponding clamps in order to ensure that they go back to the same position. Gently pull the hoses from the lower intake manifold.

Step 3: Remove the Intake Manifold

Now that the hoses are out of the way, undo the bolts that secure the manifold. Set the bolts aside for later use. Remove the manifold by raising it off the engine.

Step 4: Replacing the Gaskets

Remove the old gaskets from the old lower intake manifold. There should be two long and two short gaskets. On the new gaskets, get the short ones and put some gasket sealer on one side. Put them on the engine with the side with the sealer going in first. Seal the other side of the gaskets. Repeat this process for the other pair of gaskets (the longer ones).

Step 5: Reattaching the Lower Intake Manifold

Put the intake manifold back to its original position and secure it with the bolts you took out earlier. Now return the hoses of the water pump and radiator that were attached to the side of the manifold. Make sure that they go into the correct portion. Secure them with their corresponding clamps. Return the distributor to its original position and reattach the sparkplug wires that were attached to it. Again, make sure that they are returned to their original place. Follow the labels that you made earlier. If they are installed incorrectly, your car will misfire and will have negative effects on its running condition.

Step 6: Test

Now that everything has been put back together, start the car and let it idle for about 10 minutes. After which, take out for a drive to see if your new lower intake manifold gasket is working properly.