dumb question

[dostoy320]

Someone once told me the lower unit oil has to be changed by removing the bottom drain plug, as well as the one on the side of the lower unit, draining the oil, and then refilling it by squirting it up into the hole on the bottom. <br /><br />Now, I thought this seemed like a pretty roundabout way to change oil, but today I took the screw out on the side of the lower unit and it did look like it would be hard to get oil in there. <br /><br />So.. what's the proper procedure?<br /><br />1958 Johnson 35HP

 

[Walker]

Re: dumb question

Put oil in the bottom hole until it comes out the top hole. Then its full. Most containers of lower unit oil have a nipple tip that you stick up in the hole and squeeze the container to force the oil in.

 

[dostoy320]

Re: dumb question

Thanks for confirming my suspicions Walker. Why is the lower unit designed like that? It seems like gravity is working against you if you have to force oil up instead of pouring it down.<br /><br />How do you keep oil from spilling back out when you remove the nipple tip? Do you close the top one and create a vacuum, or just move quickly or what?<br /><br />Or...... do you take the engine off and turn it upside-down? God, I hope not....

 

[stairliftoheaven]

Re: dumb question

the oil is quite viscous so if u put the top screw back in before removing the oil can, u will only lose a drop or two at the most.

 

[Terry H]

Re: dumb question

Just move quickly...

 

[Walker]

Re: dumb question

Its really not a bad design. For one, it is easy to tell when you have enough fluid in it. If you tried filling it from the top there would be no place for the displaced air to escape and it would take hours for all the air to "burp" its way out. Vehicle rear ends have an air vent and can be filled thru just one hole. Since outboard LU's are submerged in water, an air vent would allow water in.