Steps on Replacing your Car's Intake Manifold Bolts
The bolts that keep your intake manifold in place are as tough as the engine itself, but they can still break when turned. This is especially true for old bolts or those that are heavily corroded. And once one or more intake manifold bolts have been broken, it will not only make it harder for you to remove the intake manifold for repair and replacement but also increase the risk of various engine fluids leaking. Compared to other bolts in your engine, intake manifold bolts are not that hard to remove, but replacing them still involves removing the intake manifold. What's more, intake manifold bolts are sold in sets. So even if only one bolt is damaged, it may be a good idea to replace all of them with new ones.
Difficulty: Easy to moderate
- Large locking pliers
Step 1: Detach the upper radiator hose and water pump hose from the intake manifold. Both hoses are attached to the manifold via hose clamps, so you will have to remove the screw from each clamp in order to pull out both hoses off the manifold.
Step 2: If your car's distributor enters the engine through the top of the intake manifold, you will have to remove as well. Pull out the spark plug wires from the distributor caps and remove the distributor's hold-down bolt with the wrench. The bolt is usually found underneath the distributor, and once it is removed you can take out the distributor itself.
Step 3: Take out the valve covers from the cylinder heads. The valve cover is usually attached to the cylinder through retaining bolts across the valve's upper lip. Remove these bolts with your wrench and pull out the valve covers off of the heads.
Step 4: Remove the intake manifold from the engine. The manifold is also attached to the cylinder heads by several bolts, so take them out with your wrench as well. Once they are removed, take out the intake manifold off the engine to expose the intake manifold bolts.
Step 5: Use the locking pliers to grip the broken bolt. To maximize the grip of the pliers, turn the adjustment screw on the bottom of the pliers clockwise. Grip the bolt as close to the base as possible; if the bolt's threads are visible, grasp the threads.
Step 6: Carefully turn the bolt counterclockwise until the bolt breaks free.
Step 7: Once the bolt has been unscrewed, replace it with the new bolt.
Step 8: Replace the intake manifold and other components you have removed. Make sure that all the bolts have been tightened based on their recommended torque.
Tip: Soak the broken bolt in penetrating oil several days before the day of remove them to make it easier to remove the bolt. But don't add oil on the day itself; this will make it hard for the pliers to grip the bolt.