Help with boat motor

Mack in N.C.

Old Mossy Horns
Got a little 2.5 mercury that has always run like a charm.. been pretty easy maintenance on it. Had to rebuild carb last year . anyway I store it in my building attached to a rafter so it is up right. Went in there yesterday and this motor leaked grease? all over one of my stihl chainsaw cases. Included is a pic of the hole (arrow pointing to it) that the grease came out of and what the grease looked like. Is this a seal that has gone bad that I need to replace?? tks Mack
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nccatfisher

Old Mossy Horns
Contributor
I am betting it is carbon/fuel residue that is usual from a 2 stroke slobbering. Probably drained down from the exhaust housing and isn't anything to worry about. Not grease at all.
 
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nccatfisher

Old Mossy Horns
Contributor
what worries me is that it has never done this before.
Carb bowl may have been completely full this time and expansion with heat forced it by the needle and seat. It leached out and went down the cyl and out the ports and down the exhaust housing. If you tore the foot off it and looked up that exhaust housing and sprayed it with carb or brake cleaner you would see a ton on that crap come washing down out of there.
 
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reelly1

Guest
Would agree with above. Just unburnt fuel and oil. Sometimes can be a sign of it not running on one cylinder/ busted fuel pump diaphragm or something to that effect. But with that small of a motor you would have noticed that.
 

Mack in N.C.

Old Mossy Horns
99 percent of the time I run the carb dry but I may not have last time,

is that why it may have done this since all the other times there was no gas in carb?
 
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Firefly

Old Mossy Horns
My 40 Mercury and my 25 Yamaha does this and have every since I bought them. Shouldn't be an issue at all with your motor. I never run the carbs on my two outboards dry a good outboard mechanic I used to use his services told me not to years ago. I crank mine up and run them on the water hose until they are hot about once each month, never had any issues at all with the carburetors doing that..I also use marvel mystery oil in the fuel and Quicksilver 2 cycle outboard oil and non ethanol gas..
 
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Mr.Gadget

Old Mossy Horns
Just a weep hole
my Johnson 30 always did that.
Befor that the 125 and 10 hp.

If you go to a boat stack you will see a bag on a lot of the lower units because of the same.

You can check and or change your lower unit and see it should be fine to give you more piece of mind.
 

Mack in N.C.

Old Mossy Horns
Just a weep hole
my Johnson 30 always did that.
Befor that the 125 and 10 hp.

If you go to a boat stack you will see a bag on a lot of the lower units because of the same.

You can check and or change your lower unit and see it should be fine to give you more piece of mind.

I am sure now it is ok but it just worried me as I have had this motor 12~ year and it had NEVER done this before. just strange this was the first time as see it is supposed to be common .
 

DuckyDave

Eight Pointer
Contributor
If you ran the Motor at slow/idle/trolling speed for a long duration shortly before storing it, this oozing could be fully expected. When 2'strokes run at low speed the oil tends to not burn fully. At higher RPM a more oil-rich mix is needed to prevent galling/sieze-up between piston rings and cylinder wall. At higher RPM's the oil is completely combusted. Manually mixed gas/oil must be mixed for worse-case (high RPM). Older OMC engines with VRO oil mixing would self destruct if idled/trolled a long time then suddenly run at high RPM--the VRO had a low mix of oil in the carb and fuel supply "pipeline" when suddenly more oil was required. Engineers eventually figured it out.
 

jgcpa

Spike
What you didn't show is where this hole is on the motor. Could it be a missing drain plug for the lower unit? My old 2hp evenrude doesn't have a weep hole like that...
 

nccatfisher

Old Mossy Horns
Contributor
What you didn't show is where this hole is on the motor. Could it be a missing drain plug for the lower unit? My old 2hp evenrude doesn't have a weep hole like that...
You plug that hole and in cold weather you will have a busted lower unit. That is the purpose of it to let accumulated water from the inner housing get out.
 

JoeR

Eight Pointer
Any chance the carb is leaking fuel into the motor? Maybe if the float needle was seeping it would leak fuel into the motor and wash a bunch of carbon out of it along the way.
Joe
 

Mr.Gadget

Old Mossy Horns
He should have it taken care of by now if he still has it being this post was from several years back......
 
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