Missing screw in lower??

[north45]

I was installing a new bilge pump today and when I was through I notice a puddle of oil under my lower unit[crying].

I isolated the leak pretty quick, but for the life of me, I'm not sure what it is. I have 1981 Johnson 50HP, that I think has a 1982+ lower unit on it. I just bought a couple of months ago. Anyway, this is what the schematic looks like

But this is what the lower looks like, notice the hole I have circle in orange, that is where the oil seems to be seeping from. I can't see any threads in the hole but it goes back a little ways. It definitively isn't a hole I knocked in it, somehow. However, none of the schematics I look at have this hole [confused]. Is this the pinon bearing retaining screw or what, #3 on schematic?



Any help is greatly appreciated.

[Daviet]

It looks like the drain hole for the exhaust housing. It is not uncommon for unburnt fuel mixture to drain from there, it mixes with the carbon in the exhaust system, it's really messy.
Double check your lower unit oil level, the leaking oil should look different than your lower unit oil.

[hidef]

#3 is the Phillips head screw. The hole you circled is a drain hole put there by the factory. The oil you see weeping out is most likely unburnt fuel. If you have checked your lower unit and there is no water in than you are fine.

[north45]

No, this is not 2 cycle oil it is a light brown, like brand new 4 cycle oil. The guy I bought it from said he had just changed the lower oil.

I just measured the hole and it is 0.150 inches in diameter and 0.5 inches deep (i pushed a small wire in until i felt it stop and measured the wire). Also so I lowered the outboard to normal trim and it started leaking in seconds. I took a picture so you can see what I'm talking about. I don't have the right screw driver to loosen the oil level screw, I'll have to get one tomorrow.

[north45]

anyone have an idea?

[levi_tsk]

dude thats a drain hole .... i have 4 johnny rudes -ones an '81- trust me its a drain hole and thats fuel oil water mix
put some on your fingers and smell it -bet you dollars to donuts it smells like burnt oil and gas ....

[emoney]

It's definitely a drain hole. If you don't believe Levi, put a set a muffs on her and fire her up and then get back there and "eyeball" that hole. You'll get wet, lol.

[daselbee]

It is a drain hole, but with a very steep tilt to the engine, and a leaking upper driveshaft seal, gear oil can flow out of the gearcase, and then drain out the hole you are indicating.

There is something wrong under the waterpump. I had a 1979 V4 doing the exact same thing. Do a pressure test on the gearcase.

[Joe Reeves]

In complete agreement with Daselbee. That is a drain hole which is located at the extreme lower portion of the water pickup area. A seal leakage in the top driveshaft bearing/seal housing (under the water pump) will result in the exact leakage problem you describe.