Gear case oil fill mistake

[rainman99]

1985 Johnson 90 Hp.. I put gear oil in the oil level hole untill it was full. about 6 oz. what should I do now?

 

[coolguy147]

Re: Gear case oil fill mistake

ummm put in the screws,,, lol make sure u put new gaskets on them to prevent water intrusion

 

[5150abf]

Re: Gear case oil fill mistake

Ya, you are okay I would just remember to change it before too long just in case you get a leak.

Gear oil and lower oil are almost identical except the lower oil has additives to deal with water intrusion so as long as you change it again this year you will be fine.

I have gotten in the habit of cracking my lower drain plug every other trip just to check for water, oil comes out I am fine, water, the lower needs attention.

 

[Willyclay]

Re: Gear case oil fill mistake

If you literally put the gear oil "in the oil level hole unitl it was full", you may have another problem because 6oz. does not sounds like enough for a complete refill. Lower unit lubricant should be filled through the lower of the two holes in the gearcase. That forces air out the top hole as the lube level rises. Proper procedure is to remove both screws, fill from the bottom hole until oil appears in the top hoile with the motor as close to vertical as possible, insert the top screw to create a seal before removing the lube tube/fitting and then insert the bottom screw quickly. Don't forget to tighten both screws. The experts recommend new "O" rrings/seals on the screws at each service interval. Good luck!

 

[dajohnson53]

Re: Gear case oil fill mistake

1985 Johnson 90 Hp.. I put gear oil in the oil level hole untill it was full. about 6 oz. what should I do now?

It's unclear whether you're concerned about (a) the oil you used (b) the technique you used or (c) the amount you used.

Regardless, why not just drain out the 6 oz and start anew, using the right oil in the right amount, put into the right hole? Willyclay's post tells you how to do it, in case you're unfamiliar. You can get "proper" outboard lower unit gear oil in any boat shop and most big box or hardware stores.