25HP seeping black stuff from vent hole

[swinada]

I am new to outboards and just got this motor, it ran fine the other day when i tried it out. It seemed a little slow(sluggish) to get going but on high speed she ran fine. first fireing up it backfired a couple times.
Now it has been sitting a few days in my yard and yesterday i noticed some black stuff seeping from a ? vent hole on the lower gearcase. I wiped it off but today it is there again.
Can someone tell me what that hole exactly is for, is it part of the exhaust system? And what is the black stuff? I assume the engine is running to rich and it might be because of that, but as I said I'm new to outboards and dont really know yet how they work.
Here a picture to help explain.

I also noticed that the Rich - Lean adjuster on the front of the engine is not connected, how can you determine how far out you have to turn it out to be in the right position? (like turn all the way in and then 2 3/4 turn out or something like that) It is a 1976 25HP engine.

 

[elkhunter338]

Re: 25HP seeping black stuff from vent hole

I believe it is probably part of the exhaust system, not 100% sure. My Johnson has thru hub exhaust.
However I have the same black stuff seeps from my outboard when sitting. It is the oil from the exhaust, the richer I run it the more black stuff comes out. I run mine about 40:1 (2001 15hp johnson).
My dads 1995 seeps the same black stuff out of it after it sits for a few days to several weeks.
At the end of the winter I have about a quarter size oil drop on the floor where the motor sat all winter.

 

[swinada]

Re: 25HP seeping black stuff from vent hole

wow that was a quick reply thanks. So your saying I should not worry about it.

 

[samo_ott]

Re: 25HP seeping black stuff from vent hole

Is is the normal goo byproduct of the engine. It's unburnt oil/gas and exhaust and water spewing out. That's why 2 strokes are frowned upon compared to 4 strokes.

 

[swinada]

Re: 25HP seeping black stuff from vent hole

Well thank you, I guess I have lots to learn. Today I learned that this things have a pin that can shear in the middle of the lake. good thing there was someone there to tow me back to shore. First I thought I lost my Prop, but it was only a pin that sheared. Now where to get such a pin Saturday night since I wanna be boating tomorrow again. ( I sacrificed 2 old drill bits will see if that works for a pin)

 

[elkhunter338]

Re: 25HP seeping black stuff from vent hole

Drill bit I am sure is a ok temp fix. Do not forget about it it will rust and break on you.
I another shear pin can probably be had via your boat repair shop, maybe hardware store (stainless pin), or try Iboats, or mason marine. I have ordered genuine Johnson parts through mason marine and got good service.
Has the water pump ever been replaced in that old motor and does the thermostate work. Couple of things to check on an older motor.

 

[swinada]

Re: 25HP seeping black stuff from vent hole

I already replaced the drillbit as I wasnt sure how long it would last, drillbits tend to brake pretty easy. And yes it did start to rust right away.
I do live in a part of the world without any boatparts supply stores for the next 250-300 km's depending which way i go. Just for an example I tried finding the correct sparkplugs the other day for this motor. Well I did not find any in town, checked 4 stores that sell plugs. I ordered a package of 10 off e-bay for the price i would have paid for 3-4 at the local dealer if they order in. So for now I have purchased for $2 a 3/16" Zinc Plated rod and cut myself a bunch of pins. Will see how they hold up and if they rust too.

Dont know if waterpump has ever been replaced but i seem to get a pretty good stream out the back. Dont know about the thermostat. But I believe the PO has done quite a bit to this engine. He seemed to now what he was talking about where I am just starting to learn about outboards.

He changed it from a push start to remote key start which is pretty nice.