Metal shavings in the lower unit gear oil of my 70 hp Mercury

[whataday]

I've got a 70 hp Mercury about a 1982 model. Checked the lower unit gear oil and found some metal shavings on the drain plug. What could this mean?

 

[Faztbullet]

Re: Metal shavings in the lower unit gear oil of my 70 hp Mercury

It is normal to find shavings on magnet, if you can rub them between finger and it dont "poke" you are ok, if you can feel metal or its large rough chucks .........Mierda!

 

[oldman570]

Re: Metal shavings in the lower unit gear oil of my 70 hp Mercury

Was there any water in the LU gear oil when you checked it? Usally metal shavings on the drain plug magnet is a indication that the bearings or gear hard surface area is wareing and will need to be looked into. Could also be metal from the clutch dog and the mating surface of the gears to it. This will happen if the motor is shifted slowly into gear and the clutch dog dose not engage fairly quick. I shift my motor fairly quick with a steady motion which helps with the unwanted ware of the clutch dog an gears. JMO
Oldman570

 

[whataday]

Re: Metal shavings in the lower unit gear oil of my 70 hp Mercury

There was no water in the oil, that is what I was checking for when I found the metal shavings on the magnet. I was getting ready to change the lower unit oil. I'll go back tomorrow and drain the rest of the oil and see if they are large pieces or just fine shavings. Can the metal shavings be coming from the upper part of the motor, or is that all completely separate from the lower unit?

 

[aussieflash]

Re: Metal shavings in the lower unit gear oil of my 70 hp Mercury

No it can't and yes it is separate.Don't panic,thin shavings are normal.Most important is no water in l.unit.
There are washers/gaskets on both vent and filler plugs,they should be replaced as they are the most common source of water intrusion.

 

[whataday]

Re: Metal shavings in the lower unit gear oil of my 70 hp Mercury


So, there was no water, it was just very black. And the attached pic is what the plug looked like. When I rubbed them between my fingers, it just dissolved, so I am guessing I am ok then? Thanks for all your help.

 

[Faztbullet]

Re: Metal shavings in the lower unit gear oil of my 70 hp Mercury

You are good, just refill it with a good marine gear oil.

 

[whataday]

Re: Metal shavings in the lower unit gear oil of my 70 hp Mercury

Will do, thanks for all your help.

 

[whataday]

Re: Metal shavings in the lower unit gear oil of my 70 hp Mercury

So, I refilled the gear oil tonite. But I'm concerned I didn't get enough oil in it. I used a pump, and filled it from the bottom drain until it ran out the top, but when I got done, I still had about 27 oz of oil in my 32 oz bottle. I would've thought it would take much more oil than that, since my 115 Johnson holds about 27 oz's. Does anyone know how much oil this model is supposed to hold? Thanks,

 

[ajgraz]

Re: Metal shavings in the lower unit gear oil of my 70 hp Mercury

About 12 oz.

 

[oldman570]

Re: Metal shavings in the lower unit gear oil of my 70 hp Mercury

Capacity for your 70hp Merc is as ajgraz states 12.5 oz. for small gear cases, but newer 1987-89 large gear cases should take 22.5 oz. of gear oil.

 

[whataday]

Re: Metal shavings in the lower unit gear oil of my 70 hp Mercury

Thanks. I went back and did it again today, and it had air in it, so I just kept pumping till all the air bubbles quit coming out, and it ended up taking about 12 oz or so, of course I used a lot more pumping it out the top vent, but I believe I got it right this time, thanks for your quick replies.

 

[Maxz695]

Re: Metal shavings in the lower unit gear oil of my 70 hp Mercury

It does call for pumping it in slowly so air potckets don,t get created in the unit as well as tilting the engine slight ly back and forth to get the oil to settle and a rest period is recommended before toping it off to allow setteling of the thick oil.