Help with adding oil to lower unit

[Outboard]

I am told the Yamaha T 25 hp 4 stroke is the same engine as the Merc, 25 hp 4 stroke called the big foot.

I bought a used engine, said to have been used once, and am encountering a bag of problems, I didn't know cute women could lie.

Anyway, a self induced problem (hit a submerged tree) resulted in a broken prop shaft, loss of prop and all the gear.

I am now ready to assemble but notice there is only one plug screw located very low on the lower unit barrel, it seems like a drain.

Other engines I have owned, have an upper screw plug which is removed for filling the unit with oil. I connect the oil pump to the lower hole, pump up the lower unit with oil until it pours from the upper hole, replace the plug screw in upper hole, remove pump from lower hole and screw in the plug.

How do you add oil with only one lower hole? How much oil does the lower unit carry?

Any guidance would be very welcome. Thanks

 

[overthere]

Re: Help with adding oil to lower unit

there is two holes on that unit whats the model number?

 

[Outboard]

Re: Help with adding oil to lower unit

Maybe I was not super clear, I have the Mercury 25 bigfoot 4 stroke, which is said to be built by Yamaha which is Yamaha 25 T 4 stroke.

The Merc. model number is: 1F25203ZD

Thanks for your help

 

[Ray Neudecker]

Re: Help with adding oil to lower unit

I think you will find Yamaha built the power head and Mercury the gearcase. likely to have better luck on the Mercury forum.