How to change lower unit oil?

[Mac Daddy]

Its a 74 Mercury 402 40hp. I am not to familiar with this engine. How do you change the lower unit oil?<br />Thanks

 

[merc16]

Re: How to change lower unit oil?

ihfreak 402,<br /><br />if you look around the front of the gearcase you should see a screw abouut the diameter of a dime there is also one one foot above it these screws mark the top and bottom of your gearcase remove the bottom and top screws with a pail under it to drain the gear oil after it has drained, YOU MUST FILL THE LOWER UNIT BY THE BOTTOM SCREW HOLE!!!

 

[merc16]

Re: How to change lower unit oil?

ihfreak 402,<br /><br />if you look around the front of the gearcase you should see a screw about the diameter of a dime there is also one one foot above it these screws mark the top and bottom of your gearcase remove the bottom and top screws with a pail under it to drain the gear oil after it has drained, YOU MUST FILL THE LOWER UNIT BY THE BOTTOM SCREW HOLE!!! <br />and keep filling the lower unit until gear oil exits the top screw hole and then quickly put the bottom screw back on and then the top screw and then your done the reason you have to fill it from the bottom is to allow any trapped air to escape! and remember the screws coul be on eithe left or right side of the gearcase hope this helps!

 

[Mac Daddy]

Re: How to change lower unit oil?

Duh!! I see it now....for some reason I just didnt see the drain...lol o well.<br /><br />THanks a bunch