2. These holes are plugged with special squeeze plugs (spherical plugs), which are subject to replacement each time the engine water jackets are cleaned, as well as if defects caused by corrosion are detected. The accompanying illustration shows the release plugs located on the right side of the 4.2 l engine.
Note: If defects are found in even one release plug, it is correct to replace all of them.
3. Drain the cooling system.
4. Remove components/units installed in the engine compartment of the vehicle and restricting access to the release plugs to be replaced.
5. Using a hammer and center punch, tap the outer edge of the plug on one side into the hole.
6. Use tweezers to grasp the opposite edge of the cork that has turned outward and pull it out of its hole.
7. Thoroughly clean and dry the hole for installing the release plug.
8. Lightly coat the outside edge of the new plug and the walls of the bore with Stag type joint sealant.
9. Apply the plug to the hole and using a piece of pipe or a socket head of a suitable diameter (equal to the outer diameter of the plug) push the plug perpendicularly into the hole.
(See the source on the portal: «NISSANBOOK.RU»)
Note: The slightest distortion of the plug in the hole can lead to the development of coolant leaks.
10. Install the components removed for access.
11. Fill the cooling system. With the radiator cap on, start the engine, warm it up to normal operating temperature and check for coolant leaks.