Water Pump not Working?

[Kekker77]

I have a 1969 Johnson V115 Hydro Electric Outboard, I hooked it
up to My water hose and started the Motor, it runs Great
but there is No water coming out the Water Discharge.
Does it only pump the water when it heats up? Is there
something wrong with the pump?

 

[alldodge]

It should always pump water
When was the impeller changed?

 

[Kekker77]

I just bought the Boat & Motor at the End of April
and had it out once, My Brother said the Over Heat
Light came on then went out. I was Changing Spark
Plugs and ran it after, that's when I noticed no water
coming out Anywhere.​

 

[alldodge]

New to you means, change the gear lube. Make sure no water is there
Drop the lower and take the pump apart

 

[F_R]

1. You simply cannot test a water pump by running on a hose. The pump is not pumping when you are doing that, only allowing hose water to pass through.

2. If you have any doubt at all, check the water pump. The light came on, that qualifies as "doubt".

3. Examine the pump before ordering parts. That year had a serious problem with impellers separating from the internal hub and burning the motor up.

4. If it still has the aluminum impeller housing, replace the whole thing with an updated water pump kit with plastic housing and stainless steel liners.

 

[Kekker77]

1. You simply cannot test a water pump by running on a hose. The pump is not pumping when you are doing that, only allowing hose water to pass through.

2. If you have any doubt at all, check the water pump. The light came on, that qualifies as "doubt".

3. Examine the pump before ordering parts. That year had a serious problem with impellers separating from the internal hub and burning the motor up.

4. If it still has the aluminum impeller housing, replace the whole thing with an updated water pump kit with plastic housing and stainless steel liners.

I found in my manual that it Only pumps cold water as needed, it circulates as does a Car cooling system. when it reaches the temperature that it is set for then it pumps cold water.

 

[F_R]

That is basically true. But it is not an either-or thing. It always adds some lake water regardless of thermostat position. This is necessary in order to cool the exhaust. The thermostat is always sampling the temperature and opening and closing as necessary to maintain desired temperature. That means that some water will always be discharged, varying in amount according to thermostat status.

 

[mike_i]

Replace the water pump and test the thermostats.

 

[racerone]

There is only 1 thermostat ( vernatherm ) on that motor.

 

[oldboat1]

I found in my manual that it Only pumps cold water as needed, it circulates as does a Car cooling system. when it reaches the temperature that it is set for then it pumps cold water.

(but the water pump impeller spins and pumps with the driveshaft. It is not temperature controlled.)

 

[F_R]

(but the water pump impeller spins and pumps with the driveshaft. It is not temperature controlled.)

All right, to explain the system better. Of course the pump pumps water all the time. The water goes up to and through the powerhead, then is presented to the thermostat. If the 'stat says it is too cool, the water returns to the pump for recirculation. But a portion is discharged to cool the exhaust and that portion is replaced by cold lake water. When the 'stat says it is warm enough, it opens and water is discharged instead of returning to the pump. This is a continuous process, 'stat and recirculation varying constantly. But yes it is always pumping and adding and/or discharging as necessary. Actually it is pretty simple.

 

[oldboat1]

thanks FR -- as long as the OP knows that. Think he has the idea that the pump provides cooling on an as-needed basis.

It is indeed pretty simple.

 

[Kekker77]

All right, to explain the system better. Of course the pump pumps water all the time. The water goes up to and through the powerhead, then is presented to the thermostat. If the 'stat says it is too cool, the water returns to the pump for recirculation. But a portion is discharged to cool the exhaust and that portion is replaced by cold lake water. When the 'stat says it is warm enough, it opens and water is discharged instead of returning to the pump. This is a continuous process, 'stat and recirculation varying constantly. But yes it is always pumping and adding and/or discharging as necessary. Actually it is pretty simple.

Your right, it is Thermostatic controlled. the water that is hot goes out the Exhaust past the Prop on this Motor.
then when it gets up to fully heated then it discharges out the ports.

 

[Jucebachs]

Greetings! I’m new to the forum thing… I have an 1975 85hp that’s is having cooling issues as well. Owner previously said they just put on a new water pump… I believe they only replaced the impeller… I took a apart the vernatherm set up and the plastic valves had melted completely about the light and heavy springs. Cleaned the springs up, got her a new vernatherm and both plastic valves… still having issues… I’m thinking the water pump impeller was not installed properly and I need to go ahead and drop the lower for a gander… thoughts?

 

[racerone]

Correct.----Pull it apart and check the pump impeller.-----Still too many folks who think you can run these things dry.

 

[tphoyt]

Jucebachs
Please start your own thread
Thx

 

[Jucebachs]

Jucebachs
Please start your own thread
Thx

Sorry!
Again, I’m a noob to this forum. My apologies for any offense!

 

[82rude]

No offence taken by me .Its just more polite and efficient for you to start your own thread and get specific answers to your issue and not get a possible confused answer.