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propshaft seal leaking again or unburned 2stroke?

So to test if the thermostat is stuck open... the cylinder head will stay pretty cool? It should hurt after 5 seconds if it's at the correct temp?

Thanks for all the help racerone.. I'm just starting out with outboards and this site is helping me learn my way around. Wish I would have caught on to what you were saying earlier but I figured if water was coming out of the tell-tale then everything was OK. Guess I'm lucky the thermostat wasn't stuck closed. Seems pointless to have a tell-tale that doesn't reflect whether the motor is actually being cooled. I had a look at the "cylinder and crankcase" diagram but still cant find the thermostat on the actual motor. Is it under something that is not on the diagram? Everything is painted white..

http://www.marineengine.com/parts/johnson-evinrude-parts.php?year=1980&hp=15&model=J15RLCSD&manufacturer=Johnson&section=Cylinder+%26amp%3B+Crankcase
 
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I think it is quite clear that it is under the water cover on the cylinderhead.----------------No point looking anywhere else !-----------------What do you mean by your " telltale being pointless an indicator ".-----------------------It indicates that the water pump is working !!!!!!!!!!!
 
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Seems simple to plumb the tell-tale at the end of the system.. and have water diverted to the exhaust when the thermostat is closed instead..... making the tell-tale truly confirm engine cooling is taking place.. Isn't that how other motors work? My buddy's merc pee's harder when the therm is open.

Guess I'll need to reseal the water cover on the cylinderhead too huh?
 
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Johnson and Evinrude had some " wonderfully brilliant engineers "---------------------They made a fine machine too !!!!!!
 
pulled the thermostat this morning... seemed fine and passed the hot water in a pot test. I reinstalled it and there was no change in the idle(has always idled a little rough-I was hoping fixing the thermostat would make her pur).. I'll try de-carbonizing next and post results...
 
had a big fishing trip today so I decarbed the motor last night and opened my plug gaps to .036 from .030. They motor ran alot better in the morning and by the afternoon it was clockwork. It went from missing pretty often to almost never missing at all (idling)... We shall see if the dripping is decreased... I'll post back.

Thanks for all the help guys....
 
There's still a puddle of oil on the floor under this motor... I'm gonna try messing with the lean/rich idle adjustment now that she's running smoother.
 
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I recently re-sealed this lower unit, and again I'm seeing black oil on the floor under the motor. The oil in the gearbox is still clean and blue. I smeared some of the black stuff on white paper to see if there was any remnant of the blue coloring but it smeared very brown.....no blue tint at all. Is it possible for this much unburnt 2-cycle oil to slowly drain from the exhaust leg?? This is my first through hub but none of my buddies have oil on their garage floors.

I thought the seals went in pretty well.. The only thing I can think of is that I might have used sealant for the metal on metal part of the prop seals? Also I didn't replace the shift linkage seals but I don't think that would be leaking from the hub. Any opinions would be appreciated...This is a 1980 johnson 15hp by the way..

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I realise this this is an old post but have recently had a similar problem. The boat had thick unburnt two stroke right through the exhaust system. Initially I though it was an after effect of the boat having been sitting without running for twelve months, that somehow oil from the VRO had deposited in the carbies and fuel dried from bowls or some such. After running the boat for a while this problem continued. Turns out the choke had malfunctioned and was running full choke the whole time. Now fixed no problems with unburnt oil. So I’ve posted this future reference for this who may have similar problems
 
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