How to Change the Gear Oil in a Yamaha Outboard engine 

Great video of Yamaha 4hp . Thanks bud 👍👌

Thank you so much! ..Have the same motor its looks fabulous runs well so thank you for showing me how to change the Gear oil!

Thank you very much for this instructional video.

Brilliant again thank you.

Wonderful Video!!!!

Awesome extremely helpful.

As others have pointed, lower unit oil with that milky color (colour) has been contaminated by water. Water from outside is getting into the lower unit through seal(s), gasket(s) or a crack/hole in the case. If the source of the leak is not eliminated further damage is inevitable. Water is a bad gear lubricant and given enough time will lead to catastrophic gear damage. If left unrepaired this lower unit will fail. Simply replacing the old oil with new will not "fix" this problem Drain the oil, pressure test the lower unit to determine where the leak has occurred. Spray soapy water around all the machined openings into the lower unit. Open one of the oil fill/drain holes, using a hand pump to pump low pressure air into the lower unit and then look for bubbles coming out of the source of the leak/water intrusion. During manufacturing there are limited openings machined into the lower unit; the drive shaft, shift shaft, propeller shaft and oil fill/vent openings. They are all designed to keep lubricating oil in and external water out and are protected by seals and gaskets. Once the leaking seal/gasket is identified it is are replaced. Then the unit is pressure tested again to verify the leak has been eliminated. If it holds pressure (as per manufacturer's instructions) the unit is then filled with oil (exactly as you did here from the bottom hole upwards) and returned to service.

Wondering if you could change the gear oil while the lower unit is off to service the impeller? Thanks for the set of videos! Very clear and well photographed.

Hi mate have you a video of crankcase gasket removal ? Ty

thanks buddy, like 👍👍👍

Are you aware of or have you ever converted the Yamaha 4 stroke to allow remote shift and throttle control?

What is the length of the M8 bolt you drilled out, please?

Awesome

I would love to have the screw and pump.. can this be bought online.

Thanks

Instructions and a Scots accent too....bonus.

How does one take of the prop, I have fishing net stuck behind the hub. Split pin is visible

Whats the wash plug used for?

Theres water in your oil which means theres a gasket leak somewhere

Change your output shaft seal........ Water ingress is evident

Why is it filled from the bottom plug and not from the topplug?

Why not fill the oil from the top ?

I think you have water in your gears bro.

milky color, because of water inside its not good

Uh oh water in the oil

15hp

If you fill the oil on the top plug you can flush the old oil out and all that slush to.i am Just yousing common sense

You got water in your gears

I squeeze mine in with a mustard container.