Water in gearcase

[scuba4me]

I inherited a decent older boat that has a Evinrude 140hp VRO 1986 outboard. The motor runs and compression is ok. I drained the gear case tonight and the first thing that came out was clear water about 1/4 of a cup. Then black tar like oil and water mix (about 1/2 a cup) and then mostly black gear oil. The little magnet on the bottom screw has a few small pieces of metal dust like stuff on it.

The motor was not serviced in a long time, and last time it ran in the water was 4 years ago. I was started 2 years ago out of the water just to check it. I took the prop off and inspected the seal underneath it all looks fine. I put 1/2 a quart into it and re-drained it to try and clean it out and the refilled with fresh Hi-Vis oil.

I have the service manual and I?m ready to break it down if needed just haven?t run into this one with my other outboards and this is the biggest one I have owned.

My questions are below thanks for any pointers:

1.Is the amount of water possibly due to condensation from sitting for so long ext. is it normal for an older motor with 300 hours to have a little water in the gearcase?

2. Should I go run it and drain it and look for more water or could I cause more damage i.e. is what I stated above an absolute indication of a bas seal?

3. If it?s a bad seal what seal is the likely culprit - what should I look for when I break it down?

Thanks for any help.

 

[Cofe]

Re: Water in gearcase

Just a question: Is this a salt water motor?

 

[scuba4me]

Re: Water in gearcase

yep

 

[scuba4me]

Re: Water in gearcase

I know salt water causes corrosion but its ben sitting with the water in the verry bottom of the lower unit not on the gears and bearings. So I guess I should just break it down and see what I got? Or should I go run it for a few minutes and see if it gets more water in the gearcase first?

 

[arnettjs]

Re: Water in gearcase

I'd run it a bit and see what you have. No reason to break it down just yet. Doesn't seem like it was that much water in there, maybe the seal is seeping just a bit.

 

[scuba4me]

Re: Water in gearcase

Ok is there a process I should go on? I was thinking if I run it on ears for a while and then check for water it might help me fiure out if its a lower seal or an upper seal. I would not call it a little water but then again I don't usualy see any water in my other motors. Id say it was 1/3 cup total. I took a viedo of me draining the water and oil out. I'll post that tonight so you guys can see what I got - and maybe get a few laughs...

 

[Vic.S]

Re: Water in gearcase

If it were mine I would allow it to drain thoroughly .... overnight perhaps.

Then fill it with the cheapest automotive engine oil I could find
I'd give it a brief run on muffs or in a barrel or whatever ...just long enough to churn up all the muck inside and then drain it again.
Possibly then repeat the exercise, several times if necessary, until the oil draining looks reasonably clean.
Then refill with the correct gear oil ( or perhaps just for the purposes of testing it some EP 90 automotive gear oil )

Finally give it a try to see if it all works and then check the oil for signs of water.

Chances are that there will be water still getting in ... these seals don't heal themselves once they start to leak they most likely carry on leaking.

The choice then is to pressure/vacuum test the unit or simply renew all the seals and be done with it.

No it cannot be condensation there is no way ( apart from duff seals) that moist air can get in! If moist air can get in so can water!

 

[wilde1j]

Re: Water in gearcase

The method to find which seal(s) is leaking is to a) drain the gearcase b) pressure test the gearcase by pressurizing to no more than 15 psig c) submerge gearcase in water and look for bubbles to see where it is leaking. Three possibilities besides the fill/drain plug gaskets are: 1) prop shaft, 2) drive shaft, 3) shift rod

After repair, test by pressurizing. A good LU should hold some pressure for at least 45 minutes.

An OEM shop manual would be very helpful here.

 

[scuba4me]

Re: Water in gearcase

Vic.S
Thanks for the draining and motor oil tip. I?m going to do that to clean it up inside as suggested.

wilde1j
Thanks I ordered the pump kit and the gearcase seals kit today. I will probably just take the lower unit in and have it tested if it?s not too much, or I will just change out all the seals and cross my fingers. I have the shop manul so Im good there.

Does anyone know if the water pump gaskets or the screws could be causing the leak on this model motor? Maybe I should replace it and then have it tested?

 

[nymack66]

Re: Water in gearcase

In most cases its the seal on the shift rod, Pressure testing in a tub of water is the way to go shows if any leaks and where ...

 

[wilde1j]

Re: Water in gearcase

Water pump has zero to do with the gearcase, other than sitting above it. Pressure test shouldn't cost too much ... only takes a few minutes to know if it's leaking and where. Prop shaft is most likely culprit due to mono getting wrapped around shaft and wrecking the seals. But you never know until you test it.

If it's been a while, I would do the water pump, since it's easy now.

 

[Tim Frank]

Re: Water in gearcase

Make absolutely certain that you change the seals on the drain plugs.
As practice, I change them every time I change the oil.
These are often a source of leakage...especially if you don't know the motor's history.

 

[1kruzer1]

Re: Water in gearcase

Make absolutely certain that you change the seals on the drain plugs.
As practice, I change them every time I change the oil.
These are often a source of leakage...especially if you don't know the motor's history.

A huge +1 Tim Frank. Do not overlook the possibility of simply bad plug seals. My motor is case in point. Lower unit held pressure overnight, yet I got water inside. Replaced both drain plug seals on the advice in this forum. No problem and no water since. Turns out what was likely happening was the drain plugs held pressure from inside, but when the warm sunny lower unit was submerged, as in launching off the trailer, the quick cool down may have created a slight negative pressure in the gearcase and a little water was being drawn in past the plug seals. I suggest trying the 50 cent fix (plug seals) first and check frequently to determine if water is still getting in. I know it has spared me the cost of prematurely having the gearcase resealed. Good luck!

 

[tav1]

i have the same water intrusion problem in my g/c, 92...Johnson 175 2 stk.it is a 50 cent fix but if your draining and refilling to find a problem will run you a few bottles of gear case. did a pressure test and it held 10 psi for 10 mins.and it held. then i refilled it, now to empty it and see how the oil looks. if it looks bad then a vac is next.

 

[Crosbyman]

hopefully 10 years later he fixed it ...or sold it