Oil & some water leaking from front of prop?

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DaveInGA

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I finally bought a cherry picker and removed my 86 Merc 75 HP from the back of the boat. While on the boat, the original owner had a very long transom saver, holding the engine and propeller at an angle that would have prevented any leakage of the prop area due to simple gravity. (See pics in my boat resto post, link in my sig.)

When I removed the motor from the boat and it became vertical, the front of the prop first leaked some clear water, then some very black, dirty oil.

When I drained the lower unit, I saw no water/milkiness in the lower unit oil. However, this has got me thinking there's a problem with the prop area, perhaps a seal of some sort.

Anyone have any ideas?
 
The amount was hard to judge, perhaps 1/3 cup or a bit less. It was nasty smelling stuff, very much like the lower unit oil. Shows signs of "seeping" after the majority drained out.
 
Well, if you leve it standing upright with a bowl under it and the oil ends up looking just like the lower end oil then you problably have a problem. Did you change the lower unit oil yet? It should look like honey, black is very bad, milkshake is worse...

Jamie
 
crazymanme2 said:
Its unburnt oil from the exhaust cavity.Common

This would be my guess as well.

If the oil that you drained out of the l/u wasn't the same color as what has leaked out, most likely it is not one and the same.
 
I had already changed the lower unit oil a couple weeks ago, so it would be honey colored. I did use a good bit of oil sprayed into the cylinders when I did the compression check, since the motor had sat up for a good number of years.
 
DaveInGA said:
I did use a good bit of oil sprayed into the cylinders when I did the compression check, since the motor had sat up for a good number of years.

Most likely, that is your culprit.
 
crazymanme2 said:
Its unburnt oil from the exhaust cavity.Common
^ Yep

You said the lower unit lube was clean with no water, then there is no seal issue. Make sure to replace that little seal on the drain screw so you keep it that way.

Bufford
 
RBuffordTJ said:
crazymanme2 said:
Its unburnt oil from the exhaust cavity.Common
^ Yep

You said the lower unit lube was clean with no water, then there is no seal issue. Make sure to replace that little seal on the drain screw so you keep it that way.

Bufford

Sounds like you figured it out.....
 

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