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Lower Unit leaking lube

O

oily

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I have a 1968 Johnson 9.5 HP o

I have a 1968 Johnson 9.5 HP outboard. Used it last week with no problems and this week before taking it out I found a puddle of lower unit lube under the lower unit. Also there was a small rubber plug laying in the puddle. Both filler screws seem to be in place and sealed. The fluid seems to be leaking from a small port on the very back of the lower unit under the exhaust port. Is that where the rubber plug came from and if so is that really all that holds back the lower unit lube is a small rubber plug?

The motor is stored off the boat and transported in the bottom of the boat when driving down the road so I am assuming something rattled loose.

Any thoughts?
 
I would suspect that small hol

I would suspect that small hole that you refer to is simply a drain hole to allow the lower exhaust housing to fully drain (prevent a freeze crack).

As to the plug (????)

Did you in fact check the lower unit to see if that's what was leaking. An oily liquid coming from a drain hole is normal as burnt/unburnt oil and gas collect in the exhaust housing and once pulled from the water drip/drain their way down and out....
 
"Per 1971 9.5 manual exploded

"Per 1971 9.5 manual exploded veiw of lower unit, there does seem to be a plug that goes directly under the exhaust port, rubber or not doesnt say. Look at your motor and see if its there. I'd say its about 3/8" plug hole. Also see if there's water in your lower end oil. If there is, it'll look like milky oil. Graham is right in saying that all kinds of stuff comes out after running. My lower end takes about 9-10-12 ounces of lube. Is the oil spot/puddle big enough to have come from such an amount of oil?"
 
"Thank you for the comments an

"Thank you for the comments and posts. Sorry for the delayed response, I have been away for a few days. I have had a chance to play around with the motor a bit and a similar old Johnson motor. It seems the hole in the lower unit on the motor I have is something that has been added along the way. It looks like nothing more than a drain hole to get water out of the exhaust housing just like Graham said. It seems the hole was drilled in at some point down the road and did not come from the manufacturer these extra holes (there are actually two one up high and one down low, both going into the exhaust housing). As for the rubber plug - I have no idea why it was there. I have a feeling this motor has gone through quite a few owners in its day so it is hard to say. What looks like is happening is that the seal between the lower unit and the exhaust housing is leaking a bit of oil into the exhaust housing when the motor is laying on its side in the boat and then when I stand it up straight to put it on the boat the oil is running out of those drain holes. I will let you all know at some point next week if that is in fact the case, I will be checking the seals and replacing if necessary.

Thanks again for the thoughts"
 
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