I checked my Mariner outboard today.....

[ProDave]

Yes it's getting close to that time, so I set it up in the garage with the usual bin full of water and tested it.

It's a Mariner 4, short shaft 2 stroke outboard.

It ran just fine and peed from it's pee tube okay.

But I noticed something I had not noticed before.

Near the top of the leg, facing rearwards is a small projection, angled downwards at about 45 degrees with two holes in it.

It was blowing a mixture of exhaust gas and a very fine mist of water from these two holes.

I can't say I have noticed that before. The majority of the exhaust was correctly bubbling up from the bottom of the leg.

Is something wrong that I need to look at, or is this normal?

 

[duncan99210]

That's what the holes are there for - to let out some of the exhaust gases at idle. There should also be a fine mist of water present in the blow out, this confirms that there is a flow of cooling water into the exhaust. In fact, the majority of the cooling water flows out via the exhaust in the hollow leg; the pee hole is mainly a confidence builder, showing that there is water circulating from the impeller. If at any time you only get exhaust gas coming out of the holes with no water, then you should check that the vent from the engine has not become blocked.

 

[ProDave]

Thanks for the reply. so it looks like all is well then.

 

[VicS]

Thanks for the reply. so it looks like all is well then.

Absolutely. All normal.

You have changed or at least checked the gearcase oil for any signs of water ingress .