Johnson Motor Problems

[Nate Dogg]

I have a 70's Johnson 10 horse outboard motor that is having overheating problems. It does not shoot any water out of the upper hole on the shaft. I took the lower unit apart, flushed all the ports out and water flowed freely through the upper hole when I used my hose. When I put everything back together, started it up with the lower part of the motor in a trash can of water, still no return on water out of the upper hole. Any ideas?

 

[Nate Dogg]

Re: Johnson Motor Problems

The rubber propeller seemed to be in good shape. Is it possible that it is in backwords? It sits in there very tight and I had to bend the fins to get it in. Could I have bent the fins in the wrong way? I thought this would be the logical solution.

 

[Kyle Anderson]

Re: Johnson Motor Problems

I had the exact problem with my 88 9.9 Johnson, no water would exit the engine while running. This is a real good indicator of a bad water pump. It may look just fine, as did mine, but be worn out. My suggestions are to replace the impeller (rubber portion of the pump) and be sure to either clean the metal housing very well or replace that also. Another problem area could be the soft rubber fitting that attatches to the metal housing, if it is cracked or loose fitting, replace it. I actually burned a head gasket out due to overheating problems caused by a bad impeller. Take the time to do these simple preventative repairs, and your engine should be ok.<br />mofojohnson

 

[Kyle Anderson]

Re: Johnson Motor Problems

Nate dogg<br /><br />The impeller can't go in backwards. Just get a new one even though it looks fine.