Mercury F5RZ-6K292-B5A Seal

Remove the negative cable from the battery then, take off the accessory drivebelt. Subsequently, remove the engine timing belt. Place a suitable bar through the camshaft pulley hole to hold it; remove the retaining bolt and extract the sprocket. Standing bare and using a suitable hooked tool, pull the seal out. Coat the new metal lip of the seal with clean engine oil, position it and pull it over with a long bolt of the same thread size as that of the pulley bolt and use a suitable driver piece such as a large socket. Replace the sprocket and tighten the bolt to the required value of torque. The rest of the installation process is just the opposite of the following removal steps.

Remove the timing belt, and take off the camshaft sprocket(s) as required. Even if only one seal is leaking, it is prudent to replace both at the same time.