89 Johnson 120 heat Alarm after water in my gas

[dnadorozny]

I have an 89 Johnson 120 outboard that took in a little water while trolling, through an open gas cap. The water caused the motor to run pretty rough for about a minute (had to restart 3-4 times), but eventually it ran fine at trolling speed. When I started to drive faster to head inland, after about 1 minute the engine bogged down suddenly and a steading ringing from the controls sounded. I came in on my kicker, but once the engine was off for a few minutes, it started fine and would troll no problem. But as soon as I speed up, the engine bogs everytime now and the alarm sounds. I am assuming this is the "hot" alarm and my engine is heating up when the plugs are working hotter at the higher speeds. Because I can troll no problem at low speed, I am thinking the problem could be my impeller is not pumping enough water to handle the heat generated at the higher RPM's, and needs to be changed. My only hesitation on this is that this problem of overheating only started after I had the water in my tank, so did I possibly do some damage inside the head unit from water that is causing the "hot" alarm to go off at the higher speeds? Again, the engine runs 100% on startup and low speed trolling. In fact, once when the alarm came on, I simply let the engine continue to run in neutral (not smart I know), and the alarm went off in about 3 minutes and ran fine. When I feel the water coming out of the spiggot on the back of the motor, it feels extremely hot to the touch, but this may be normal. I'm crossing my fingers that all I need to do is change my impeller. Any advice?

 

[DJ]

Re: 89 Johnson 120 heat Alarm after water in my gas

Water is heavier than gasoline. I suspect that you have some water "puddled" in your float bowls or the oil injection/fuel pump unit.<br /><br />The engine needs much more fuel at above idle speeds.<br /><br />The alarm is either: fuel restriction or interupted oil flow.

 

[dnadorozny]

Re: 89 Johnson 120 heat Alarm after water in my gas

Thanks for the quick response! So is this a fairly straight forward repair I can make by simply removing parts and draining/cleaning, or should I leave this in the hands of a professional? Also, is the alarm sounding because of restricted gas flow, or because of over heating due to the restricted gas flow?