Gearcase leak…where? how?

[nj-boatbuilder57]

If it was the seal on the vent plug, then how is this oil-water-foam getting up into the impeller housing? Any ideas? That’s the part that has me scratching my head…

[dave-bernard]

that is unburnt fuel from the motor. not lower unit oil.

[crosbyman]

had similar issue (foamy oil) on my 75hp ETEC last year . took the LU home for winter testing pressure tested 15 min at 12 psi and negative 10 psi Vacum for 10 min no leaks

used new crush nylon washers when I filled it up and stored it last winter

this season at bed time for winter last week I drained the oil….. NO WATER had come in the LU

conclusion…. don’T reuse old crush nylon washers 🙂

Joining AOMCI has priviledges 🙂

[billw]

The stuff in the containers is out of the gear case itself, though, right?

Long live American manufacturing!

[nj-boatbuilder57]

In my first post, second photo: Yes….the light green stuff (center & left containers) is the oil I drained from the gear case. By contrast, the container on the right (dark green) is a sample of new oil from the same container that was used to fill the gear case in the spring.

The sludgy stuff up around the impeller housing is fuel-oil residue? Very interesting. If I can rule that out, then this may be as simple as plug washers.

[fleetwin]

Well , like others have said, the stuff near the upper seal is probably just unburnt fuel/water/exhaust emulsion.
Dig out any old washers from the gearcase cavities, replace the washers, and refill with OEM quality gear lube….
Don’t overthink this too much, looking for issues that might not be there…

[nj-boatbuilder57]

and refill with OEM quality gear lube…

Any suggestions what should be used? In ’57, the OEM said OMC type C which, if I’m not mistaken, was SAE90 gear oil. Lubricants have come a long way since then…is there anything wrong with the WestMarine 80W-90 Hi Viscosity marine gear oil that I’ve been using? Is it not “OEM quality”?

I know there’s some gear oils available that are specifically marketed as “Type C”….but they all say that they’re for electric shifting, which I don’t have. Does it matter? Should I be using this?

Don’t overthink this too much, looking for issues that might not be there…

That may be the best suggestion of all! …and I thank you for it!

One last thought: the more I read, the more I find people saying “never re-use the plug washers”. Guess what I’ve reused? 🙂

But as I look over the ‘net, I’m not seeing a real clear picture of what washer to use. The plastic ones seem to be the most common, but I’m not certain which to buy. Johnson part # 27-284 is the correct-but-obsolete OMC number. What is a modern, plastic equivalent? Is it Sierra 18-4248-9? As absurdly overpriced as these are, I’d prefer not to make a purchasing error .
.

• This reply was modified 2 years, 6 months ago by nj-boatbuilder57.
• This reply was modified 2 years, 6 months ago by nj-boatbuilder57.

[Mumbles]

Surprisingly, Marine Engine has the washers for less than Amazon. You can also try your local BRP or Mercury dealer as they both use a 3/8″ drain plug on certain models.

http://www.marineengine.com/

[nj-boatbuilder57]

Casual observation:

– a 5 pack is $3.79. That’s $0.758 / ea.
– a 50 pack is $39.46. That’s $0.789 / ea.

Who would buy a 50 pack when ten 5-packs is cheaper?

I found these at West Marine….same deal, only worse!

– a 5 pack is $3.79. That’s $0.758 / ea. (same as marineengine.com)
– a 50 pack is $44.99. That’s $0.8998 / ea!!

Who thinks this stuff up?

Anyway…thank you for the info.

[crosbyman]

Don’t go complaining… my pack of 10 from my local BRP ETEC dealer was $17.82 yes $1.72 each 🙁

they are nice folks but….

Joining AOMCI has priviledges 🙂

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