'78 johnson 15

[bonzoscott]

I have a project outboard that I just got running. It looks bad and has seen some bad days. I ran it for maybe a minute and no water is coming out of the hole/tube in the lower cowl. I also have a '73 9.9 that is fine but noticed the difference in size of the water outlet tube. The '73 appears to be 3/8 and the 78 appears to 1/4. Then I have read about this Tell-Tale. is that what I have on the '78. Anyway, I took the water pump apart and it looks fine. Any sugestions?

 

[bktheking]

Re: '78 johnson 15

They didn't make a 9.9 in 73, maybe you are thinking a 9.5, totally different motors. The 78 has one. Sometimes they plug up, take the telltall and tube off the the water jacket and try blowing through it to see if it ins't blocked, the fitting may be blocked too.

 

[jay mendoza]

Re: '78 johnson 15

Running in a tank or trash can of water, it takes about 30 seconds or so for the water to appear, and if you are using muffs, it takes even longer as the water has to fill up the entire mid section before it will come out the exhaust releif hole(tell tale hole). The engine has to be at a fast idle with muffs or the water level will not maintain due to low pump speed.

A bad upper water tube grommet can also cause problems if it's leaking, but you usually get some flow out the tell tale/ exhaust releif hole. The normal flow is a spray/mist.

 

[bonzoscott]

Re: '78 johnson 15

I had it in a barrel, and ran for at least a minute all RPMs. So it has only the one water exit, the tell-tale? I thought about shooting some air from both ends but the thermostat will be closed. Thanks for the info. I'll hit it again tonight!

 

[Daviet]

Re: '78 johnson 15

Most of the water will come out around the prop. As suggested, check and see if the tell-tale is pluged. Use a piece of trimmer string and shove up the tube with the engine running and see if water comes out. The tell-tale is an indicator that the water pump is pumping, not that the engine is cooling properly. Start the engine and run at fast idle and hold your hand on the cylinder to see if it is overheating. Let it run for a few minutes and see if you get water out of the tell-tale. You may have a thermostat problem.