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Mr Wizzard Mr Wizzard is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 55
Default Mercruiser A-1 gear lube consumption


"Jim" wrote in message
ink.net...
That is a drain hole for the cavity that is in front of the water pump and
shift shaft. Any leak in the area could drain to the hole you speak of.

If you have warranty you shouldn't touch anything for fear of giving them

an
excuse to void it.


Yup - also think I'm getting the picture here too...
Correct me if my thinking is off here. Shift-shaft
is on the starboard side, and water pump on port.
Since port side is bone dry, and s.b. side a tad wet,
I suspect shift-shaft bushing seal. Also, (finally)
understand the shift shaft bushing thing now. So
I been seeing pics of the ss "bushing", and tools
to screw in/out the bushing, but failed to under-
stand how a hard plastic collar bushing could be
a seal. Finally found a web page that explains it.
Its a hard plastic threaded bushing with slots on
the top (to screw it in/out), BUT, its got n O-ring
down inside of it. Somewhat common for the O-
ring to pop out, or walk itself out of hte center of
the bushing, and just float around the shaft on the
top of the bushing. So..... Got an appointment
for Aug 16th (2-weeks from now), so we'll go
from there. Question is, is it bad enough to have
to stop using it for the next 2 weeks - thats what
I have to evaluate now. Fear being getting water
in the drive. Also, had another dealer tell me on
the phone that the shift-shaft seal also acts as a
pressure relief valve. (?) Don't understand that
as all! - if so, pressure would pop the O-ring out
of the hard plastic shift-shaft bushing, but that
action would be permanent, right? How could
an O-ring act as pressure relief and remain in tact?
(guess I'd just have to see it all apart on the bench)




Jim

"Mr Wizzard" wrote in message
. ..
"long periods of WOT" is defined as 5-10 minutes max.

No, it wasn't me with thermostat problems. Boat is
1-year old, with less than 50 hours on it, so I'm
assuming that any major work is covered under
warranty, so I'm sure I'm ready to tear into it.

Also, right after I made that post lastnight, I went
back outside with a flashlight after spending a bunch
more time googling stuff. I *DID* find something
that is suspicious. I found what felt like a thin film
of oil.lube on the back edge of the cavitation plate
on the starboard side (on the lower unit) There is
a small weep hole towards the rear just above the
plate that is about 3/16 - 1/4", and on the startboard
side hole, I can look in and see what appears to be
something that is "wet" with oil. So I'm thinking that
is is where my oil is leaking - out that weep hole.

Does anyone know what these weep holes are for?
And is the shift shaft directly behind the starboard
hole? (appears to be some sort of verticle rod
behind that hole). Is it possible that my "shift shaft
seal" is leaking? - I did find one post about a common
prpblem with the A;pha-I gen II and shift-shaft seal,
and that there might be a bushing retrofit? - Anyone
know anything about this ?

Thanks!




"Jim" wrote in message
ink.net...

"Mr Wizzard" wrote in message
. ..
Thanks for all of the great info. I'm still greatly dissapointed.
As many of you recall, this 2005 Bayliner 175 is my first
real boat (that I bought brand new jast June), and now I
got this gear oil consumption problem. I've recently called
the dealer about it too. Did some more tests, and find that
it uses about 2 Oz of oil for every 1-hour of running.

So, the question is, where is the most probable place
for the leak? Prop seal, driveshaft seal, or water pump?

And what could of done this? dealer dude (on phone)
doesn't seem to think that engine alignment would do it.
Would running it at excessive speed do it? Not too
long ago, I was running it at WOT for really long
periods of time - could that have done it?

I've only had the thing out 4 times this year since
winter - could something have happened over
winter? (Seattle area). I did scrape the fin on
drive way, but I consider that pretty minor.

How rare is it to develop gear lube consumption
problems on a 1-year old Alpha-1 I wonder?

And are replacing seals somehting that I can do?
(very mechaincally inclined). Issue is that dealer
says they won't be able to get me in till late Aug.
I was thinking that if its a prop seal, that maybe
I can just replace it. Also, whats involved with
changing the oil seal on the upper half? and the
shift lever? So what, 4 places the lube can leak
from, right? prop deal, upper drive shaft seal,
shift lever, and water pump area?

Thanks!

Momentary spurts of wide open throttle are ok once in a great while.

Long
periods of WOT running is abusive. If it weren't for the protection of

your
gear lube resevoir, your stern drive would probably be trash by now.

In order to find your leak, you need to remove the stern drive and

split
it.
Remove the prop and water pump upper body. Plug the small holes that
transfer oil between halves, and do a pressure test. You will see the

leak.
If it's the water pump base seals that are bad you won't need any
special
tools. Otherwise start reaching in your pocket for those crisp

hundreds.
If
you're a decent mechanic, you can sit down with a genuine OEM manual

and
teach yourself how to repair or rebuild a stern drive.

While the drive is split, it would be foolish not to replace the upper

water
pump body kit.

If you are the fellow that was having the thermostat stuck with sand,
that
might be part of your problem. The grit gets imbedded in the neoprene

seals
and wears away at the stainless steel shafts. Pretty impressive the

first
time you see it.

Let us know what you find.

Good luck Dude,
Jim