Johnson Cooling System

[boltonc]

I have recently acquired a 1976 75HP Johnson Stinger. I performed service on the engine and it seems to run flawlessly, however, I am unsure as to whether it is cooling properly. The Clymer service manual I am using refers to a water disharge from the "tell-tale" nozzle. I do not know the location of this nozzle. Also, another Johnson engine I have seen, discharges water with the exhaust throught he prop. My engine does not do this. I want to be sure the engine is properly cooling and not blocked before I venture out with it. Any help with this matter would be greatly appreciated.

 

[G DANE]

Re: Johnson Cooling System

Hi Boltonc<br /><br />The tell tale nozzle it below top of engine on left side seen from the boat. If it sprayes water, you cant miss it. If you test run in a barrel, are you sure the water pump is completely under water, some of them have to be, to pick up water. If the impeller hasnt been changes this year, I would recommend you to. Look and tell us more !

 

[G DANE]

Re: Johnson Cooling System

boltonc<br /><br />Just thinking a bit about it, i am not sure the 76´has a tell tale hole. The 35 hp has t t hole from 79´and foreward.<br /><br />On some models the water squirts a bit through the iddle exhaust on back of the leg to ensure you cooling is o.k.<br /><br />I dont have the manual for your motor, maybee someone else can tell exact when they read this post.

 

[fatboy]

Re: Johnson Cooling System

the tel-tale tube is also called the pee tube. The can get blocked with debris easily but will not in it's self cause any problems. Just make sure warm water is flowing out of the engine when it is running. If you start to overheat while under way it may be the water deflectors in the motor. I had an old evinrude 200 that had rubber water deflectors that corrected circulation in the motor for proper cooling. Not sure if you motor has them or not but if the come loose you will know it..

 

[its-a-sweater]

Re: Johnson Cooling System

The 76 OMC's didn't have a telltale hole.<br /><br />I think they started that in 79.<br /><br />You should have some "spray" coming out of the holes at the top of the mid section at idle and a good stream at higher speeds. Steam coming out is NOT OK.