Here is a great tech tip that Mike demonstrates for any members that are working in their Twin Cam, cam compartment. It is always a good habit to remove, clean, and inspect the Twin Cam oil pressure relief valve any time a cam plate is removed. Especially, if there had previously been some type of catastrophic damage that left a debris field within the motor.
The Twin Cam oil pressure relief valve assembly consists of only a plunger, a spring, and a roll pin. A specialty tool is needed to disassemble & reassemble. However, the tool is something that is not difficult or complex. You can easily make it yourself. If you prefer to purchase the tool, it will typically cost around $50. It can be purchased from Jims Tools USA.
To disassemble the valve, use the specialty tool to depress the spring and tap out the roll pin with a 1/8″ punch. Keep a firm grasp on the tool so that the spring does not shoot out, across the room. A small magnet can be used to extract the plunger from its bore in the cam plate. Now, all you need to do is clean the plunger, the plunger bore, and the spring. Coat the plunger with clean motor oil and verify that it can slide smoothly within its chamber.
To reassemble the Twin Cam oil pressure relief valve, simply work in reverse. Slide the plunger and spring into position. Depress the spring with the specialty tool and tap the roll pin back into its original position.
Inspect the oil pressure relief valve every time you remove your cam plate.