habbi wrote:
I have a 2001 250 Johnson XXL which was new in May 2003. I just took it out
and drained the gearcase. It was full of water, not milky oil, I mean pure
water, the end had about a tablespoon of milky oil. I am 100 % sure it was
full of new clean oil when I put it in the water back in May. There are 200
hours on the engine. I know I should have checked/changed it sooner but it
is a 31' work boat and hard to remove from water. I pressure checked it and
no leaks but I have not vacuum tested it as I do not have the pump and
gauge. Anyway dealer is going to cover it under warrantee. Should the
warrantee cover a complete rebuild as the internals are probably corroded?
Or will they just change the seals?


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I resisted as long as I could hoping someone; just about anyone else;
would state the bleeding obvious, which is;

(i) This is just more of the same bad design from OMC & when the Bills
bleat "they all do it" I don't feel any better as you won't when you
find out how much this piece of crap will cost you to "fix" but even
then it won't be "fixed".

(ii) The problem with these OB legs is the very fact that they are
sealed!!!;

(a) In use they get hot because the drive elements (gears bearings
etc) are all deliberately under designed (go through the books & for the
HP etc they shouldn't even work at all, the fact they do for the short
time they do is a miracle)

(b) The main reason they do work is the case is alloy & can dump the
massive heat made by the undersized parts straight into the water,
however the transport to the case for that heat is mostly the via oil.

(c) The case is tight (small) that there is lots of expansion so they
deliberately leave a tiny bubble of air in the top to allow for it, the
idea being, this re-expands when you shut down & the leg very very
quickly cools so contracting the oil level inside.

(d) The OMC BS ideas about positive & negative pressure testing re
just more of the same from this bunch of idiots, because the only time
the leg sees positive pressure is as it heats up & expands but at this
time the totally unsupport from the powerhead input shaft is thrashing
around like a rubber band (again get off your arses & have a look in the
books, the shaft is way too small for the HP in any premises & even if
it were the "right" size it's unsupported (bearing in the middle) over
too great a length not the flex around (the fact it's soft SS is just a
side curse:-))

(e) So now the leg is heating, oil & alloy expanding, the input shaft
is flexing all over the place & the bubble of air in the top is
"supposed" to just compress?? In a brand new setup it might for a while
but after that it just escapes out the top seal under the water pump.

(f) You shut down the leg cools as it contracts, where is no air
bubble left to expand so the leg sucks water back in, end of story the
design sucks, literally.

(g) Next time you use it the same happens but with a twist (little in
house joke there don't fell bad if you missed it:-)), this time there is
NO AIR BUBBLE to absorb the expansion!! So the leg pressure goes sky
high, in so doing it crushes the seals tighter & tighter trying to
contain it, but with all the other things, vibrating prop (see how tight
they want it & then think about why??), input shaft flexing around at
5000rpm etc etc & they soon give up, letting a little of that now water
oil mix out, till you shut down again & it cools, now it's even easier
to suck more water in.

I know you're not really interested in anything but throwing money at
brain dead dealers Habbi but................ there is a "fix" to
mitigate against the effects of yet another OMC design defect:-)
(somewhat ungracious I freely admit, however I can assure you it does
work:-)

(i) Put new seals in it, as it heats the extreme pressure mentioned
above makes the lip seals push harder cutting into the soft SS shafts,
(again more poor OMC design) so replace all the seals, yes your shafts
are already damaged, but they're not worth replacing, sorry 'bout that
chief.

(ii) If you think the first part of this post bothers you Habbi try to
stay really calm now on:-) You need to;

(a) Put a small copper tube into the leg, some here bore a hole in the
top filler plug & silver solder the tube in there or you can get all
creative & thread a fitting into the top (roof) of the gearcase so the
modification stays totally inside & out of sight.

(b) However you choose (we always give free choice:-) you then run the
tube up the leg (inside if keen, clever & cunning or outside if you want
to get lots of queries from onlookers at the wharf:-) into the engine cowl.

(c) Up in the engine cowl you put an oil reservoir. There is room it
just doesn't look like it:-). People here use all sorts of things from
an upturned sauce bottle with an air bleed in what was the bottom, to a
snazzy looking auto bottle (those early coolant recycle bottles with the
hose going into the bottom are popular) Again exercise some free choice
here!!!

(iii) So what happens now is;

(a) There is no air bubble in the top of the leg, any left gets
squeezed out within the first few hours of use:-)

(b) As the leg gets hot the oil expands but meets little resistance &
just goes back up the tube into the oil reservoir.

(c) As the leg quickly cools it never shows a pressure less than the
outside water because the reservoir is well above it so the leg will
always suck oil down rather than suck sea water in. Yes even on your
damaged shafts:-).

(d) The seals & shafts will last many times longer because they never
see high leg pressures.

If you want to get a better understanding of what I'm talking about
you're always welcome to come down here & I'll have the blokes show you
over a proper Taipan OB to see how it should really be done, although
prepare yourself, the transmission(s) is actually "designed" so the
major elements are 6" in diam!!! & that's just for 80 HP @ 4000rpm!! OR
if that is too much for you:-) Maybe try having a good quiet look at any
Mercruiser IB/OB drive & you'll see that this is exactly how they do it.

No no honestly you're welcome; it's no trouble at all; no no please
Habbi it's my pleasure to be able to help; yes I know it's christmas but
surely you must have got some other presents??; Oh stop it Habbi I'm
blushing now; honestly all I really want is a simple thanks for the info.

K