Motor peeing question

[crwtuna1]

I have a Mariner 1987 ELO 30 and it does not pee when started. The previous owner said he replaced the impellar.

If the thermostat is not opening, will water still come out the pee hole when the motor is running?

Thanks again!

 

[FuzzyGrub]

I don't know the particulars of your model, but my '98 Merc 25HP will just dribble until the thermostat opens. I had the thermostat fail closed, and with just the dribble it would start to overheat. It ran fine without stat until the new part arrived. Merc made the Mariner, so could be a similar design. If it is too hot to place you hand on the water jacket, shut it off. Hopefully, someone knows the particulars of your year/model.

All the other small outboars I've owned, started peeing almost immediatly. Mostly Evinrudes and Nissans. The bigger outboards take a little bit to fill the cooling passages, before they start peeing.

 

[DaleH]

Don’t know Mariners either, but just worked on a OMC 15hp where the Owner says they just did a full waterpump change - and no peeing - and I know it should.

I removed the rubber hose off the block and condition was the same, so I removed the fittting off the block and it was all crudded up inside, as that’s a natural ‘collection point’ for any sediment, as the block threads are a bigger diameter than the hole in the fitting.

Carefully poked the crud out w/ wire and she now pees like a racehorse. So check that out …

 

[MrGiggles]

Not pumping at all or just taking a little bit? Every Merc of that vintage I had would take a few seconds to start pumping. Whether it had anything to do with the thermostat, I don't know, but they behaved the same with a new impeller or old.

If it's not pumping at all there could be a lot of different causes. Blocked lower unit grates, water tube not lined up properly, impeller installed wrong, or a blockage in the cooling circuit from sediment/rubber from the last impeller.

 

[thill]

Find the pee hole and follow the hose up to the block. Carefully remove the hose from the fitting, and start the motor on the hose. If she pees strong from the fitting, it's the hose. If it only dribbles, use a small piece of wire or similar to poke in there, and usually a chunk of something will come out.

In extreme cases, you may have to remove it, but be careful, as sometimes they are corroded and will break off before coming loose. Then you have to drill and tap the hole, which is a pain.

Around here, the most common culprits are little, tiny mud wasps they call "Dirt Dobbers" that will fill up a pee tube surprisingly fast and surprisingly deep. Sometimes, they will have 6" of nests inside a tube.

Many people stick a golf tee or any kind of little stick in their pee holes to prevent this. The nice thing about a piece of twig is that when you start the motor, the water blows the twig out, and you don't have to chase it down.

 

[bbot1967]

If it's not pumping at all there could be a lot of different causes. Blocked lower unit grates, water tube not lined up properly, impeller installed wrong, or a blockage in the cooling circuit from sediment/rubber from the last impeller.

I've done that! Put the impeller in so it was trying to push water instead of pull it.

 

[FuzzyGrub]

FWIW: I prefer using a tank/barrel to diagnois cooling problems. Using muffs, the pressurized water can mask cooling issues. I use a cut down plastic garbage can and fill with water to above the cavitation plate.

 

[wmk0002]

If you can access the thermostat easily, you could try removing it and reinstalling the cover and running the motor and seeing if it will work then. If it doesnt then you know something is clogged since the system is now unrestricted. If it does, go ahead and test the thermostat in a pan of water and make sure it opens at the correct set point (prob somewhere around 140F) and reinstall it if it passes. Reinstall it and run the motor and give it time to warm up and see if it starts to pee when warmed up. I use a IR thermometer gun to temp the head around the thermostat to get an idea of if the thermostat should be opening yet or not.

 

[crwtuna1]

Update, I started the motor and it started peeing at a fast idle and slowed as I increased the throttle. I had used string from a string trimmer to clear the pee hole as best as I could. The previous owner indicated that he had replaced the impeller, but wasn't sure if he installed it correctly. So, I guess I'm pulling the lower unit. Thanks for all the input!

 

[crwtuna1]

Peeing Update!
Took the impeller out and it is not worn and it has the key. put it back together and started it up and no peeing. I then took the thermostat out and left the cover off and NO water! I could feel it pumping air though. Where do I look next?

Thanks,
A frustrated Mariner owner

 

[LDUBS]

Are you running it in a tub? I recall a post before about concerns with not pumping. It turned out the outboard was not submerged enough into the water (does that make sense). Make sure the water level is well above the impeller (not the inlets, the impeller).

 

[FuzzyGrub]

Maybe the water line from pump is not aligned. It is usually a metal tube that slides into a rubber grommet. Check a schematic for your engine.

 

[crwtuna1]

Are you running it in a tub? I recall a post before about concerns with not pumping. It turned out the outboard was not submerged enough into the water (does that make sense). Make sure the water level is well above the impeller (not the inlets, the impeller).

I have it in a 55 gal trash can filled past the pump level.

 

[crwtuna1]

Maybe the water line from pump is not aligned. It is usually a metal tube that slides into a rubber grommet. Check a schematic for your engine.

Tube is aligned.

 

[FuzzyGrub]

The prior owner might have waited too long before changing impeller and the tips broke off and are plugged some where.

 

[Pappy]

You may have an impeller with a detached (spun) hub. Not a common issue but I have one sitting on my bench at the moment. Looks perfectly normal but if you grab the impeller blades from both sides and try and bend away from the hub you will find the issue if that is what it is.
Second. run the piece of string trimmer material back in through the indicator outlet again. Very often it takes more than once. Also verify the indicator is free and clear at the powerhead end of things. compressed air works quick as well.

 

[MrGiggles]

Even if the impeller looks okay, the fins will take an impression from the housing with age, if they're curved too much, it will not pump.

Also remove the grates from the lower unit and make sure that passage is clear, I have seen insects build nests in there.

 

[crwtuna1]

Thanks for all the input. I have a new oem impeller on the way. The pee hole is molded into the bottom of the engine cowling and I can see no hose anywhere. I have been able to get a trimmer line in about 2 inches. There was no water being pumped up to the thermostat. I dropped the lower unit and submerged it into a barrel of water and spun the drive shaft with a drill and very little water was being pumped. I'll let you know after the new impellaer arrives.

 

[crwtuna1]

pee hole

 

[FuzzyGrub]

While it probably will not cause a no water pumping issue, the pump housing and lower plate should not have any grooves in it. It will quickly wear a new impeller.