Tips On Installing New Cam Bearings

Post date: Jul 12, 2017 8:47:30 PM

Now many people don’t install their own cam bearings when rebuilding their engine because they don’t do it frequently enough to justify the installation tool, but if you are considering it, then here are some tips based on how we do it.  It really is an easy process provided that you keep just a few basic things in mind.  The first is to make sure you have the correct mandrel for your bearings.  Most installation kits are designed to handle a wide range of bearing sizes and you want to make sure your bearing can slip onto the un-expanded mandrel and that the bearing shoulder nests well on the mandrel.  

The next item is to make sure that you are putting the correct bearing in the correct journal.  Many motors have different OD’s for the different journals, so check that – it’s critical.  In the case of Mark IV BBC, there are 3 different journal sizes, so order is important.  Each box will have the bearing part number and position outlined on it somewhere.  In addition, the part numbers are stamped on the OD surface of each bearing.  Once you have the order and numbers correct, take a Sharpie and draw a line across the outside face through the oiling hole – this will be uses as a reference for installation to ensure you are centered on the main oil passage.  

Starting at the rear cam journal and once lined up hit the bearing installation rod (make sure you have the plastic cone on it to center the rod) with a 3 pound hammer sharply to drive the bearing into the journal.  

Remove the mandrel and check the centering of the bearing hole and the oil passage with a flashlight.  If good move to the next, if it needs to go a bit further, then reinstall the mandrel and tap it until it’s aligned.  Notice that the main oil passage is a larger diameter than the oiling hole in the bearing; this is to account for any small misalignment that may result during installation.  Once they are in, then the reassembly can begin!