1965 Johnson 9.5 steam or smoke?

Evinrudej

Petty Officer 2nd Class
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Dec 18, 2020
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131
Hi so I just changed the impeller on my ‘65 Johnny 9.5 wasn’t pumping good. Pumps water great now but I’m noticing either smoke or steam coming from the pee hole on the back. I don’t believe that it was doing that before I changed the impeller. To the touch the water feels hot can only hold my hand under it for 2-3 seconds. Is this a problem?
 

rolmops

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Feb 24, 2002
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Sometimes when the impeller is changed, the pipes that go from the pump to the engine block are not put together the proper way. You say that it pumps great ,but you have steam coming out of the pee hole. That to me points at the tubing not properly in place. I would check the pump again . Maybe you forgot to put that little thingy that locks the impeller onto the shaft ( the impeller key). That would cause what you just described. As for the thermostat, it's always a good thing to check it, but it worked fine before you serviced the pump and you did nothing to it, so that is probably not your problem.
 
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Evinrudej

Petty Officer 2nd Class
Joined
Dec 18, 2020
Messages
131
Sometimes when the impeller is changed, the pipes that go from the pump to the engine block are not put together the proper way. You say that it pumps great ,but you have steam coming out of the pee hole. That to me points at the tubing not properly in place. I would check the pump again . Maybe you forgot to put that little thingy that locks the impeller onto the shaft ( the impeller key). That would cause what you just described. As for the thermostat, it's always a good thing to check it, but it worked fine before you serviced the pump and you did nothing to it, so that is probably not your problem.
Imepeller key was installed. It pumps water great now compared to before. Made sure the pump was inserted into the exhaust tubing before sliding lower unit back up and bolting it on.
 

rolmops

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Joined
Feb 24, 2002
Messages
5,419
The next thing, after the thermostat, would be back flushing the cooling system. there might be a clogged passage. I love to do that by taking the cylinder head off, which is a very simple thing to do. But it can become a mayor pain in the neck if you accidentally break a bolt. I never force too much. I little heat on those bolts does prevent a lot of four letter words. I do not quite get what you mean by exhaust tubing.
 

Evinrudej

Petty Officer 2nd Class
Joined
Dec 18, 2020
Messages
131
The next thing, after the thermostat, would be back flushing the cooling system. there might be a clogged passage. I love to do that by taking the cylinder head off, which is a very simple thing to do. But it can become a mayor pain in the neck if you accidentally break a bolt. I never force too much. I little heat on those bolts does prevent a lot of four letter words. I do not quite get what you mean by exhaust tubing.
Is it possible to flush the system with a hose from the top of the thermostat?
 

rolmops

Vice Admiral
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Feb 24, 2002
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5,419
You would not clean out whatever is past the thermostat. But you can can remove the thermostat and run it. If the temperature goes down you should be alright. Before you dig into the engine and thermostat I would suggest you take a thermometer ( grab one from the kitchen) and measure the temperature of the water coming out. If the temperature does not go much over 140 you should be alright to begin with. And yes, 140 degrees will burn your fingers.
 

Evinrudej

Petty Officer 2nd Class
Joined
Dec 18, 2020
Messages
131
Problem was solved. Needed a thermo stat and oem impeller. I used a China kit originally and the new Oem kit with sierra thermostat has it cooling great no steam. Thanks everything
 
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