Small oil leak?

RTZ

Seaman Apprentice
Joined
Mar 7, 2021
Messages
34
After I had drained my LU gear oil out. I noticed some oil seeping out of a tiny hole that is about 3 inches to the right of the water intake grill, starboard side, on my 1987 88hp Evinrude. Is this normal? The hole is factory made and not sure it's purpose. There is another hole just like it about 1 inch below the water intake grill. Nothing came out of that hole. I assume they are some type of vent? I just did not think oil would come out of that one. Sorry if this is a novice question, but it is the only way I can learn. There is no mention of these tiny holes in my service manual. I am sure an OMC guy may know what I am referring to. Thanks.
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
38,434
These are cavity drains.-----Drain the water so no frosty damage occurs in cold climates.-----Any water in the gear oil you drained ?-----Or a 1987 lower unit should be pressure tested.------On a 33 year old motor a seal kit should be installed if seals are original.---Cheaper than gears and bearings.
 

RTZ

Seaman Apprentice
Joined
Mar 7, 2021
Messages
34
Thanks racerone, Yes there was water in the LU. I am replacing the driveshaft seals and the shift rod seals, because I can get to those easily and have the tools. I will then pressure test it. If it fails then it must be the prop shaft seals and I do not have the tools or knowledge for that. So it will head to a shop. Gear oil was coming up through the shift rod, so I believe that is where the water got in. Some oil seeping out of that cavity drain is Ok?
 

racerone

Supreme Mariner
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Dec 28, 2013
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38,434
Some will argue.----How much water was in there ?-------If there was a lot of water then the gearcase needs to come apart for inspection of the bearings , shafts and gears.----Or run it till it goes ---" boom "---I guess.
 

RTZ

Seaman Apprentice
Joined
Mar 7, 2021
Messages
34
There was a good bit of clear water that came out followed by the black gear oil. It was not mixed. I believe the water got in when I was running it on the muffs. The boat had not been run on the lake in a very long time but was run on muffs several times in the past couple of weeks, as I was chasing an overheat problem. Thanks.
 

RTZ

Seaman Apprentice
Joined
Mar 7, 2021
Messages
34
Is that bit of oil coming out of the cavity drain ok?
 

oldboat1

Fleet Admiral
Joined
Apr 3, 2002
Messages
9,612
likely unburned 2-cycle/gas mix (normal). If it smells like gas....
 

lindy46

Captain
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Nov 27, 2008
Messages
3,886
Running on muffs won't cause water to get in the gearcase. Bad seal somewhere.
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
38,434
Lots of water in the oil means just one thing.-----Lower unit needs a seal kit.----Simple , " pay me now or pay me later " scenario.
 
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