'95 mariner 15 hp... Not spitting water out

I just got a 1995 15 horse mariner with tiller shift, it runs good and strong, but i cannot locate it's pee stream for water outlet.

I found the exhaust port, and it has another smaller hole next to it, but nothing ever comes out of it (except exhaust)

And there a hole on the starboard side just under the head near the back, and i never see anything coming out of there.

We rode around for about a half hour the other day and the engine didnt even seem hot at all...

So... Where is the water supposed to come from?

I remember when i bought it the other day, the guy ran it in a bucket of water and i noticed water was coming out higher up on the shaft, but not from a defined hole... could the water outlet hose have disconnected from it's original out port?

I want to locate the problem before it becomes a paperweight!

My 40 year old evinrude still had its original impeller and had no problems... Could a 17 year old motor have a bad impeller?

Yes impellers can and usually do go bad every couple years (or 5 seconds if no water is running through them). I am not a Merc expert by no means but there should be a tube or fitting coming from the thermostat cover that bolts to the cylinder head. Follow the tube and you should be able to locate the pee hole.....

Thanks johny, anyone else have any input?

Ok, i found the hole, i dunno howh i missed it before... It was right where the indent was where you pick it up to put it on the boat... Duh! :shock:

So, now let me ask this... Should water ALWAYS come out of there when it's running, or only when the thermostat is open?

It should always come out of there as for the pump is always turning when the engine is turning. The t-stat will open and close as needed to supply water to the engine.

Always when running. Time for an impeller

I would think that after running for a half hour, if cooling water wasn't circulating, the motor would have shut down by itself. I had a 15hp Johnson that stopped peeing and it shut down after only a few minutes.

As stated before, the pee stream is before the thermostat so maybe there is just an obstruction in the pee hose part of the system.

There might be a blockage in the pee hole, take a length of weed whipper line and push it into the pee hole.

I'm not sure what year the Mercs changed but my 2000 doesn't pee until the thermostat opens.A very little water dribbles out but no stream until it's warm.

crazymanme2 said:

I'm not sure what year the Mercs changed but my 2000 doesn't pee until the thermostat opens.A very little water dribbles out but no stream until it's warm.

Click to expand...

My 2005 mercury 15 had a steady stream all the time. This mariner has not had a stream at all that i noticed yet... Maybe at speed it might have opened, but i can't tell with all the water splashing around back there

The manual for this motor says IF it has a thermostat the stream will only come out periodically and not all the time.

The panel on the back of the motor where the hose runs to the pee hole looks like it may be a thermostat housing... Do these things have gaskets on them or can i open this up with no fear of it leaking?

Ok, just confirmed it DOES have a thermostat, i took it out and tested it in some boiling water and it DOES work.

Also found some water in there behind the thermostat, so that leads meto believe that everything is working fine.

The guy i bought it from said that it didn't have many hours on it, it was his kicker motor

i think i might be ok, but will keep a close watch on it

Thanks everyone

Just because it opened in boiling water does not mean it works correctly. To really test it you need a thermometer in the water as it heats up to see if it opens at the correct temp.

Would here be any negative effects to removing the thermostat and running the motor in a bucket of water so that i can see the water come out?

As i stated earlier, the manual does state "if the engine has the optional thermostat installed"

Would runnin without it cause any problems?

Is this a OEM manual? Or is it a Seloc manual or something like that?

I have heard of people removing thermostats in warm salt water because of corrosion issues. But the thermostat is in there for a reason and I don't recommend to anyone to remove it.

Its the original manual that came with the motor

I just mean remove it for a short time to ensure my impeller/ water pump is working, not forever

Not sure on mercs but the pee hole (which indicates water flow) is usually before the thermostat so the thermostat has nothing to do with telling you how well the impeller is working.