Outboard lower gear oil change

[captpierre]

Been changing my lower gear oil every fall.

Yammy 115 2007.

Always looks like new.

Thinking of just checking it to see if it looks normal and maybe just topping up.

New washers.

Dumb idea or OK?

[ecmilley]

You can but pull bottom screw that's where water will accumulate though I'd just change it better safe for minimal cost

[OhioFisherman]

I changed mine every year, also in the fall, just viewed it as a cheap way to prevent problems. Changing it in the fall gives you all winter to get any problems you might find fixed before the spring rush.

[irishfield]

I do my small motors by just checking most years due to low hour use.

 

With engine VERY slightly tilted up I pull the top (vent) plug and see if the unit is full. Oil lightly trickles out and then quickly reinstall the plug. New plastic washers are a plus, but not always necessary pending condition.

 

Then I pull the lower fill / drain plug quickly. If there's water it will come out first, as it's heavier than oil, otherwise the same blue oil you put in previous years will come out.

 

If there is any visual hint it looks diluted or too runny, drain it and refill.

[Garnet]

Usually I just check top screw because I've just finished perchn. If it's oil I change after spring perchn so I change May when warm.

 

If it's white I drain and have seal job done over winter.

 

That gear oil is 80 wt so I don't like changing when cold.

[Sinker]

I usually crack the bottom screw, after the engine has been sitting for a few days, tilted all the way down. If any water at all comes out, even just a drop, I change it.

 

If the engine has been used, and there is water in the gear case, the oil will be milky. Time for a pressure test, and seals.

 

Its a good rule of thumb to change gear oil in the fall before it gets below freezing, to prevent any water that may have gotten in there from freezing and potentially cracking the housing over winter.

 

S.

[4x4bassin]

Agree with Sinker here , if there is significant water in that bottom end and she freezes over winter your going to have a big problem $$$

Seen it before on a friends 9.9HP . Bottom end housing cracked like an egg . For what it is worth I would just change it like you have been

doing and no worries .

[porkpie]

I change mine. To prevent freezing if there is any water, and I fish during the winter sometimes so I figure it can't hurt to have fresh oil in there anyway. If the winter is good for fishing, then I just give it a quick check in the spring and away we go. If I don't fish that winter then it's all good anyway.

[Garnet]

I'm doing the same thing. I check mine after fishing in fall and know if I need a repair. Then I change oil in spring just before pike and walleye. That's when my boat gets run 5-7 days a week . I want my best oil in then.