Not sure exactly, the info I'm reading just says to use a puller to remove it. It might just slide out being that it has a retainer holding it in. (Once the retainer is removed of course.) One more thing the manual says that might pertain to the task at hand; "The auxiliary shaft cover and cylinder front cover share a common gasket. Cut off the old gasket around the cylinder cover and use half of the new gasket on the auxiliary shaft cover."