proper lower unit oil change

[seastar50]

ok i have a 72 50 hp hydro electric drive , i bought sierra type c gear lub, and i want to change the lower oil, just not sure how much and pretty much how...i was told take both plugs out drain it, put bottom plug in and fill to the oil hole? , but is this right, i thought it had to be filled by the bottom hole and how do i know i have the right amount

thanks
Jeremy

 

[HighTrim]

Re: proper lower unit oil change

Take out both plugs. insert your hose in the bottom hole and keep filling until you have fluid coming out the top hole. Insert top screw plug, then a vaccuum will be created allowing you to insert the bottom screw plug. Make sure you clean the bottom screw before re inserting since there is a magnet on it that will trap small metal filings. gl

 

[kenmyfam]

Re: proper lower unit oil change

Take out both plugs. insert your hose in the bottom hole and keep filling until you have fluid coming out the top hole. Insert top screw plug, then a vaccuum will be created allowing you to insert the bottom screw plug. Make sure you clean the bottom screw before re inserting since there is a magnet on it that will trap small metal filings. gl

As Hightrim