F225TXRD gear oil - advise me please

[fairdeal]

Pulled the boat today out for 100 hour service
and here's what the gear oil looks like:



I bought it 2 1/2 years ago, with 750 hours

this is the first time I've seen the oil come out opaque / "milky"

The fiber gaskets on both upper & lower plugs looked fine
I pulled the prop - no line behind it
So I'm assuming its just worn seals

At 1600 hours now, and the engine built in Nov 2004 -

What's the most sensible thing to do?

Try to "bubble test" to see if its driveshaft or propshaft?

Or just figure "its time" to tackle them all?

TIA

[99yam40]

I would find the leak,so I know what needs to be addressed and check after fixing to be sure

but that is just me

[scofflaw]

Do you really need help with the answer ?

[DennisG01]

Check the mounting surface for the fiber gaskets - if it's not a clean, smooth surface it could be a source of water entry (old gasket, corrosion). Then do a pressure test on the drive.

Where you using the Merc Hi-Perf stuff? If so, that's good since it can deal with some water penetration and still protect. Based on the color of your oil, it looks like you might have been using that stuff.

[TownsendsFJR1300]

I'd pressure test it, then replace ALL the seals.

The two top seals (the SS springs specifically) for the drive-shaft like to break over time. One of my two was broke(no water intrusion) but I had both replaced. Less than 200 hours...

Do it right once and be done with it for several years. A lot cheaper than a NEW LU..


* Just curious, how long (time) or hours is on the oil? One year? Two plus?


When I change my oil yearly, it comes out g0lden, just like it went in (Yamaha oil)..

[fairdeal]

Update: turns out there is no major mystery
I hooked up a bicycle pump to pressure test

and with the first stroke, I could hear air whistling out of the water pump

took everything off down to the seals, added a few drops of bubblestuff:



I last changed the gear oil on April 17; have run 102 engine hours since

My current thinking: if the unit passes a pressure test after I replace these seals,

I'll leave the prop shaft seals alone

[TownsendsFJR1300]

Update: turns out there is no major mystery
I hooked up a bicycle pump to pressure test

and with the first stroke, I could hear air whistling out of the water pump

took everything off down to the seals, added a few drops of bubblestuff:

Those seals are EXACTLY the ones I mentioned in post #5. There's TWO, each up against each other.

The SS spring that wraps around the seal to keep it taught on the shaft breaks. Bet yours isn't there..The bottom is likely broke as well but you'll find that one as its captured in that machined block. I believe there's an o-ring between that block and the LU housing too..(replace)

I've posted previously, those seals simply fail over time. You flush, baby the engine all you want. Over time, the seals fail.

And most importantly, measure the DEPTH of the seals before pulling them. There is NO spec for re-installing but they should be the same as they came out..

Congrates on finding it!

[fairdeal]

well, the F225 SM seems to have a clear detail on the depth of install of the seals:



Although the entire section is written with the assumption of a full & complete teardown.

I have been thinking instead about just a nice "flush" of the gearcase with oh, paint thinner or diesel to get the residual emulsified water/oil out....

[99yam40]

over thinking this maybe
fix the leak, fill with new gear lube run for a little while and then change it again

But then again I have flushed my lower with ATF to help get contaminated lube out before, just because it was something I had sitting around

[TownsendsFJR1300]

Its probably (if the drain plug was left out), 95% gone.

I'd probably throw some 10w30 in the case and slosh it about real good.
Maybe leave it overnight upside down to get into everywhere. Then let it drain again over night. You should be good to be go then...

[fairdeal]

fix the leak, fill with new gear lube run for a little while and then change it again

But then again I have flushed my lower with ATF to help get contaminated lube out before, just because it was something I had sitting around

I'd probably throw some 10w30 in the case and slosh it about real good.
Maybe leave it overnight upside down to get into everywhere. Then let it drain again over night. You should be good to be go then...

The SS spring that wraps around the seal to keep it taught on the shaft breaks. Bet yours isn't there..The bottom is likely broke as well but you'll find that one as its captured in that machined block. I believe there's an o-ring between that block and the LU housing too..(replace)

All very helpful, guys, thanks.

Oh, the top stainless steel spring is there, Scott - "some of it" LOL




And there's signs that the O-ring hasn't performed 100% already...

[scofflaw]

Your prop seals are just as old no doubt. Simple enough, just pull the seals and not the carrier

[fairdeal]

Your prop seals are just as old no doubt. Simple enough, just pull the seals and not the carrier

Good point.

and in fact, upon a close look with good light:



Good thing I already ordered those parts as well.

But while I'm not thrilled with the prospect of pulling the carrier -

trying to pull the seals - esp. the inner - seems problematic also...

[scofflaw]

Look at that youtube video. I used a 3" deck screw after drilling with a 6" drill bit. Accidently caught both seals on the first try. Simple.. 2 pair of vise grips and a hammer, then a length of pvc pipe to install them.

[TownsendsFJR1300]

You got your moneys worth out of those seals, no doubt...

I've seen the "You Tube" video of pulling the prop seals. Looks very do able but some serious care MUST be taken NOT to screw up the prop shaft.

Also, you have the large o-ring (probably not leaking) for the carrier that's likely flattened out as well.. Reading here, that retainer ring is a b...ch to remove, and often mucho heat is needed to break the carrier from the housing...

BTW, you are doing a full re-seal!

But you'll be good for several years yet as you caught it before any damage..