How to Change a Shaky Camshaft Bearing

A camshaft bearing typically needs to be changed when the build of the engine is being changed. However, if your camshaft bearing has gone shaky, it is best to replace it to avoid engine trouble. Camshaft bearings play a critical role in the longevity and performance of the engine, and therefore, the selection of the bearings should be done very carefully.

There are different types of camshaft bearings available commercially. To be able to determine the best camshaft bearings for your car, the performance needs of the engine should be kept in mind. Here’s how you can install a camshaft bearing or replace the old ones.

Step 1 – Cleaning the Block

The first step towards the installation is cleaning of the engine parts. If there is any dirt and grime trapped between the bearing bores and the bearing itself, it can reduce the oil clearance and cause deformation of the bearing. To minimize the chances of any such thing from happening, clean the block completely. You can use a 3M scrubbing pad to scrub out the grime and then wipe it off with an old rag and break cleaning fluid.

You can even use clean brushes and warm soapy water to clean the camshaft bearing. Once you have cleaned the bearing, blow on it to dry it completely. Make sure that both the cooling and the oil passages are completely dry. After drying everything, coat the surface lightly with oil so as to prevent rusting.

Step 2 – Installing Crankshaft Main Caps

You next need to tighten all the main caps of the crankshaft according to the specifications. This should be done before inserting the cam bearings so that no distortion occurs due to cap bolt clamping. Use a fast drying solvent to clean the bore surface. Ensure that the leading edge of each of the bearing bore has a slight chamfer.

This can ease the installation of the bearing and prevent any galling action from chaffing the edges and blocking the bore. If the camshaft bearing are different in size for each of the cam bore, put them in the order in which they have to be installed. Always start installing from the rear to the forward on the block. The bearing’s oil hole should be aligned accurately with the oiling hole.

Step 3 – Fitting the Camshaft Bearings

When finally fitting the cam bearings, allow sufficient clearance between the bearing and the camshaft. If you are using babbit bearings, this clearance need not need to be too large. However, in the case of aluminum or alloy bearings, the clearance will have to be a little larger than normal. Ideally, the minimum clearance that you should give is around 0.002 inches. Further, if you have a high-performance engine, give at least 0.003 to 0.004 inches of clearance between the camshaft and the bearings.