In the water oil/ lower unit service

[Keta-salmon]

Sometimes it will be easier for us to do some service work on yamahas while they are still in the water, oil change and lower unit fluid change. {Yamaha 25, 50, 90 and 150]
Seems i heard reference somewhere of a pump to suction the fluids out, if so , anyone know of the pump name , as well as procedures, like replacing the fluids once they are out?
Any info and/or reference leads is appreciated, so far my search descriptions hasn't turned up anything.
Thanks

[DennisG01]

I wouldn't attempt this while in the water simply for saving a little time to do a haul out or putting it on the trailer. The risk of dumping the oil in the water and polluting is too great. Not to mention what the EPA fine probably is.

I could see POSSIBLY doing the engine oil since you can run the hose from the dipstick tube to the vacuum pump that is in the boat. But don't forget about the filter, if it doesn't drain. But no way would I attempt the lower unit. There's lots and lots of oil evacuator/extractor pumps out there - just google that.

[TownsendsFJR1300]

What I like the best is the "tilt n drain" set up:

How To | See Well Innovations, LLC | Forest Lake, MN (see video on how to use it.)

I've also used a drill operated pump that will pump the oil out the dip stick tube. Its much faster, does leave maybe 3/4 cup of oil (negligible) in my F150 but tends to get messy with oily hoses, dripping, etc.

For Lower units, the boat HAS to be out of the water...

[99yam40]

For Lower units, the boat HAS to be out of the water...

I would think you would need to have the motor in the down position to drain all of the lower unit lube.

Hard to do if in the water, but not if hanging on a lift

[TownsendsFJR1300]

I would think you would need to have the motor in the down position to drain all of the lower unit lube.

Hard to do if in the water, but not if hanging on a lift

Quite true BUT the OP asked specifically,

Quote: "while they are still in the water," end quote.


No mention of a lift, etc.

And actually, you should be able to drain all the LU oil
with the engine tilted up with the drain plug out.

Refilling would be a bit difficult (boat in the water) W/O water intrusion..

[zenoahphobic]

Interesting point, at what angles do you get the most oil out of the lower unit?

And it is a pity (messy) that these are not designed with a bleed tube so that they can be filled without leakage from the top.

[TownsendsFJR1300]

I drain the lower unit both level and tilted up for quite awhile as it takes some time to fully drain.

I have topped off my LU, thru the VENT hole using a smaller clear tube, stuffed into the larger normal fill tube(from the bottom).

It does take more pumping as your pushed less oil thru the smaller hose but the hose IS small enough NOT prevent air from escaping..

IF, the vent hole was above the water line, technically, you could fill it with the LU in the water.. It'd take quite a bit longer, especially with the larger LU's.

[zenoahphobic]

I drain the lower unit both level and tilted up for quite awhile as it takes some time to fully drain.

I have topped off my LU, thru the VENT hole using a smaller clear tube, stuffed into the larger normal fill tube(from the bottom).

It does take more pumping as your pushed less oil thru the smaller hose but the hose IS small enough NOT prevent air from escaping..

IF, the vent hole was above the water line, technically, you could fill it with the LU in the water.. It'd take quite a bit longer, especially with the larger LU's.

Would there be any real difference if filled this way with the engine tilted enough up out of the water?
The passage shortly before the vent screw would have little volume, so when oil appears at this angle, the unit is 99+% full anyway.

[TownsendsFJR1300]

Would there be any real difference if filled this way with the engine tilted enough up out of the water?
The passage shortly before the vent screw would have little volume, so when oil appears at this angle, the unit is 99+% full anyway.

I loose very little oil pulling the lower fill hose out, then messing with the oily screw and washer(PIA).

Topping off with the smaller hose, doesn't take a minute and I know its definitely topped off. And I do usually get a pump or two into it (again, with the smaller hose and smaller volume).

[Keta-salmon]

I appreciate all the good info, and interesting dialog. This is a great site!