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dick_inc
14-02-2005, 02:45 PM
I was wondering if some one could help me ???
I have just drained the gear oil out of the leg and it seem's to have got a little bit of water in it I mean it has not turned white but like a dark coffee colour, is it o.k. just to put new oil in it or do I have to have it pulled apart ??



Cheer's

aido
14-02-2005, 02:57 PM
i once had water in a mercury gear case,
first a bit of dirty watery crap came out followed by creamy goop.
coffee coloured oil may be old or overheated. maybe water??
depends, do you know how long its been in there?
water and oil don't usually mix too well, and in a clear container
i'd expect some water to settle on a lower level than oily sludge.

aido
14-02-2005, 03:02 PM
further, i'd drain it, refill with new oil, go for a short run (to load it up)
then drain in a clear container. if all looks good fill with new oil again
and sample some at the drain hole after every few trips out.
at least till your confident the seals arn't leaking.

Big_Kev
14-02-2005, 03:06 PM
A good submerged transmission gear oil, as made by the major brands will have additives to allow it to emulsify as much as 5% water. Normal gear oil 3%.
And the oil still will still be able to perform OK.
At 5% you can expect the oil to be very milky white.
If your oil is just a dark coffee colour, it is most likely to be from long service life, and due to be changed.
The gear oil will go dark black in colour from this point the longer it is in service.
Change the oil.
If it has a slight milk coffee colour I would still change it and monitor it. The milkier the colour the more contamination.Milky sludge is bad.
You can easily test for water in oil by putting a good drop in a very hot frypan.If it spatters it has water in it.
Cheers Kev. ;D

bungie
14-02-2005, 03:17 PM
I have had straight water in my gear box. The seal around the drive shaft went, you are better off having water in there than nothing ......... well thats what my mechanic told me anyway :)

NQCairns
14-02-2005, 03:18 PM
Good frypan idea Reel Hard!

aido
14-02-2005, 03:22 PM
definately try that when the missus is out. ;D ;D ;D

blaze
14-02-2005, 03:56 PM
read in my merc w/shop manual that if the box has been assembled with the proper merc recommended ASSEMBLING lube the oil will have have a whitish tinge to it, good idea to drain into a clear glass container and let it sit for a day, the water will start to seperate and the water will show on the bottom. I have just resealed my box and the gear select seal was leaking a little with 10 psi of air pressure. I was going to only replace the suspect seal until, while checking the water pump I found effedence that a small amout of water must have ingressed there as well. Ended up doing all the seals.
A good home made system to check for leaking seals is to get a spare oil bung and drill an 1/8 hole in it and silver solder a 3/8 diameter nib onto it (I used an old mig tip), srcew this into one of the oil fill or drain hole and using a regulater set to no more than 10 PSI of air pressure, apply the air pressure and then submerge the unit in water. There will be some bubbles from air escaping the hollow section of the gearbox, they will then stop, check around where the seals are for air bubbles. Merc recomment 10PSI for ten minutes. DO NOT APPLY ANY MORE THAN 10 PSI
Hope this is of some help to somebody
cheers
blaze

Big_Kev
14-02-2005, 05:47 PM
10 PSI seems like a lot Blaze.
But if its in the manual it must be the correct way to do it.

Big_Kev
14-02-2005, 05:48 PM
Good frypan idea Reel Hard!

Thats how suspect samples are first checked at the lab, before going the whole hog NQ.
Sounds rough but it works.
And yeah keep an eye out for the cook for sure.

blaze
15-02-2005, 02:02 AM
Kev
just rechecked the manual
10 to 12 psi for 5 minutes, the pressure is right just the test time is to long and that wouldnt hurt
cheers
blaze

Big_Kev
15-02-2005, 01:38 PM
I am still astounded by the pressure. But I guess with a submerged transmission the seals have to be able to take a lot more punishment then a conventional unit.
Cheers Kev. ;)

blaze
15-02-2005, 03:45 PM
You are probable right Kev, if you did it to a transmission or diff you would probable pop the seals
cheers
blaze

Big_Kev
15-02-2005, 04:26 PM
Yeah the Exon Valdeze would be all over the shed floor.

dick_inc
16-02-2005, 02:16 PM
Thank's guys you have helped me a heap, the oil is a milky coffee colour so I'm changing it and will keep an eye on it, I was told that the gear box was letting the water in thru a crack but after taking the prop off the crack is no were near the gear box , I'll try to add a photo of the crack , also if some one could tell me what this other thing is called ?? after taking off the prop and thrust washer this was around the leg, Sorry I'm not up to date with terms or descriptions of these parts, but after people have been telling me $h1t #(eg, your motor's stuffed )to make more money, it's time I learn't to fix it myself. my old motor is a 1984 marnier 40 hp serial no. L 40998 can any one tell me if it has 2 seals or just one at the front on the prop shaft.


Cheer's chris

dick_inc
16-02-2005, 02:27 PM
here is the crack in the gear box.

dick_inc
16-02-2005, 02:28 PM
and this is were the peices in the top pic came from.

aido
16-02-2005, 02:55 PM
thats one nasty looking crack.
that broken ring with the tabs looks like
it holds the bearing carrier in.
i'd be looking for a second hand leg
or maybe a replacement motor.

Spaniard_King
16-02-2005, 03:37 PM
Churbo,

Mate ya gearbox is stuffed :o

That crack will allow the bearing carrier to move around thus disslodging the seal which is at the foreward end of the carrier (1/2 way along the gearcase). This will allow water into the gearcase and is bound to be terminal

Not sure what that part was (the one in pieces)

Best idea would be to source a second hand gearcase and install your parts (chepaest way) you could approach a dealer and see if he will let you buy a manual.

Only problem is that most gearboxs repairs require speacial tools and it's a bastard to do without them usually ending up in tears [smiley=bigcry.gif]

IMO bite the bullet get a good second hand one I am guessing at 500-$600

Garry

Big_Kev
16-02-2005, 03:46 PM
By the looks of those pics :'(, I would say you have a major malfunction. :(
Get prepared to fork out some cabbage for a new gearbox or some big bits to fix it up. :P

familyman
16-02-2005, 04:35 PM
Sorry Churbro, :-[
A black anchor in another colour is still a black anchor :-/
Aido has the best advise in look for a replacement leg as that one is wallaby ted's brother- roo ted >:(
Once saw a similar looking (though not as big)crack on the side of a 115 yam 2stroke of recent vintage,about 94-95,told by local mechanic damage is caused by seal failure causing rust to grow on bearings and stretching case to breaking point .
I've had 2 old mercs and both have been great so if powerhead is ok then hunt down another leg :'(
good luck
cheers jon

dick_inc
19-02-2005, 02:46 AM
The gear box is still in tact the crack has not got to the gear box yet. I have had the prop off and you can put a screw driver down the inside of the leg and you have a bout 30mm before the crack reaches the gear box, I have done the test of a drop of oil in a hot fry pan, and she didn't spit , so that makes me think that the oil has been over worked, I am going to get the leg welded and the oil changed,then have to wait and see.

cheers chris

aido
19-02-2005, 05:50 AM
i suppose it's worth having a crack at that.
watch what's inside the repair, might be a thread there.

blaze
19-02-2005, 06:45 AM
The first photo is the retaining ring and it screws in to where the crack is to retain the bearing carrier, it can be welded, but the thread will need to be repaired and the heat of the welding will most likely loosen the carrier. Without the retaing ring in place the first time you put it in foward gear, the carrier will move back and you will probley strip gears and/or dog clutch. It would be cheaper to source a new housing, retaining ring and seals and rebuild your internals in to a new housing or buy a second hand leg and be careful of a simular problem
cheers
blaze

dick_inc
19-02-2005, 09:15 AM
does any one know if the mariner leg is the same as or can I use a merc.?????