lower unit oil question mariner 75

Joined
Sep 4, 2010
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12
Hello, I have a 1983 mariner 75hp 2 stroke that I just purchased and I need to know a couple of things: 1) How do I check lower unit and see if their is enough grease in it for a test run...?? 2) When i change L/U oil do i fill it from the drain until it comes out the vent..?? their are only two plugs that I can find and one is marked drain and the other marked vent 3) Should filling be done with motor completly trimmed down..?? Thanks
 

Dave1027

Lieutenant Junior Grade
Joined
May 25, 2010
Messages
1,078
Re: lower unit oil question mariner 75

No need to check the oil level. Best to simply drain and refill it. It probably less than a quart. Check the condition of the oil after it's drain into a pan. Look at the color it should be black. If it's brown or tan milkshake you have a bad seal.

To change the fluid the motor should be down or close to it. Make sure the drain hole is at the lowest. Take the vent(s) out first. Then take out the drain plug. Allow it to completely drain. Using a special pump hose that screws into drain hole, pump in from bottom till oil comes out vent. Install vent plug(s) and and then remove the hose from the drain and quickly put the drain plug back in. If a little oil leaks out that's ok because you want some room for expansion any way.
 
Joined
Sep 4, 2010
Messages
12
Re: lower unit oil question mariner 75

thank you!! I went ahead and changed it like you said. I didnt have and could not find a pump locally so i used a empty gear oil bottle i had. a little messy but got the job done. thanks again
 
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