25 HP Merc Mariner not steady pee

[merrile]

I recently got a 25 HP Mariner. I noted that when on ear muffs there wasn't a steady stream of water from the pee hole. I replaced the impellor and do see a stream but its inconsistant. meaning full throttle it goes for second the stops spits a little than pees for a second or two and so forth.

Last staturday I ran the boat for a good while water was in the 30's on the river. I have tried blowing air throug the vent all seems clear. I cannot unscreww the screens on the lower unit without breaking the screw.

Please advise.

I am not sure what year it is but the serial number id OC27779 or something.

Thanks

 

[jbjennings]

Re: 25 HP Merc Mariner not steady pee

My thoughts are a bad exhaust cover gasket set or a bad seal on the water pickup tube going to or coming from the water pump housing.
JBJ

 

[merrile]

Re: 25 HP Merc Mariner not steady pee

My thoughts are a bad exhaust cover gasket set or a bad seal on the water pickup tube going to or coming from the water pump housing.
JBJ

whats the exhuast cover gasket where the lower unit bolts into the motor? I did not replace the gasket just the impellor as for the tube don't know how to check that I did grease it make sure. hmmmn

anyways shall I assume water is cooling the head? boat ran fine all water comming out was cold when it did.

 

[jerryjerry05]

Re: 25 HP Merc Mariner not steady pee

On the hose U won't get the same amount of water as in the river.
Try to unblock the pee tube.A piece of weedeater hose in the hole will help unblock it.Back flush or compressed air(not too much)will help open it up.
The whole serial# model.

 

[carholme]

Re: 25 HP Merc Mariner not steady pee

merile;

The serial number looks good except for one number missing after the 9.

Gerry

 

[jbjennings]

Re: 25 HP Merc Mariner not steady pee

whats the exhuast cover gasket where the lower unit bolts into the motor? I did not replace the gasket just the impellor as for the tube don't know how to check that I did grease it make sure. hmmmn

anyways shall I assume water is cooling the head? boat ran fine all water comming out was cold when it did.

From my meager experience, running on the muffs may cover up a hidden water pump problem, but will not cause LESS water exiting the motor. If you have an inconsistent indicator stream, it is a problem that needs to be solved or you will risk overheating your motor.
JMO,
JBJ

 

[sojasyin]

Re: 25 HP Merc Mariner not steady pee

I've was taught years ago, when running my boat on the water, "look back there and see if water is running good out of the "pee holes". If not, then your water pump is going out.

 

[sxmerc]

Re: 25 HP Merc Mariner not steady pee

On this particular motor, the tell tale exits the lower cowling after it passes through the thermostat and thermostat housing. If the thermostat is operating correctly, you will ONLY have a solid stream of water when the thermostat is OPEN. During the motors temperature cycle, the telltale will only spurt water when the thermostat is closed, and then you will see a solid stream when it is open again. This is a common customer question with these motors, and it sounds as though your cooling system is operating correctly. FYI: Some of these motors will have ZERO water from the telltale when the motor is first started while cold, and it can sometimes take a few minutes for the motor to heat up enough to have any water at all.

 

[Bob Gilvary]

Re: 25 HP Merc Mariner not steady pee

If when running at good speeds on the water, you should have a constant stream, if not, then worry. Notice when it does pee that the water is hot, cools off then quits, when on the hose. It's particular to those engines and it's a thermostat thing.

 

[merrile]

Re: 25 HP Merc Mariner not steady pee

Is it normal for the thermostat to open then close again during operation? Once it warms up I get a stream for a few seconds then it stops again and the process repeats itself I got that both on the muffs and in the river. Once the water cycles through does it cool again close?

Well I changed the impellor knowing that I won?t need to do it for a few years so its now out of the way.

On this particular motor, the tell tale exits the lower cowling after it passes through the thermostat and thermostat housing. If the thermostat is operating correctly, you will ONLY have a solid stream of water when the thermostat is OPEN. During the motors temperature cycle, the telltale will only spurt water when the thermostat is closed, and then you will see a solid stream when it is open again. This is a common customer question with these motors, and it sounds as though your cooling system is operating correctly. FYI: Some of these motors will have ZERO water from the telltale when the motor is first started while cold, and it can sometimes take a few minutes for the motor to heat up enough to have any water at all.

 

[sxmerc]

Re: 25 HP Merc Mariner not steady pee

The thermostat will open and close while the engine is running as engine temperature necessitates. Typically when there is a good solid stream of water, the water that is coming out is usually very warm, and in some instances hot. The job of the thermostat is to govern proper engine temperature during any given running situation, so yes; the thermostat will open and close while the motor is running. As Bob mentioned earlier, this type of telltale arrangement is unique to the 20 and 25, and also some 9.9 and 15 horsepower engines.

 

[merrile]

Re: 25 HP Merc Mariner not steady pee

feel allot better going to spend some time fishing now can't wait