1985 Johnson 25HP Not pumping water

[ajohnson035]

I just bought a 1985 johnson 25 hp motor form a boat dealer. While at the boat dealership the motor started and pumped water beautifully. I got the motor home and hooked it up to my boat and into a barrel of water it started right up and pumped water then all of a sudden it stopped. I contact the boat mechanic and he said the water pump would not pump water well then all of a sudden stop he said there may be trash in there somewhere. The line from the head to the discharge is not stopped up I checked it. He said to disconnect the fitting at the head and run it and it would blow out the trash if any was in there. Please help any suggestions would be appreciated. I guess my next step would be to pull the lower unit and examine the impeller is it hard to take the lower unit off.

 

[gnarbrah]

Re: 1985 Johnson 25HP Not pumping water

I've changed impellers on 4 different motors so far including my 88 Johnson 20 and it's not that big of a deal. Just make sure you follow the diagrams (on Johnson/Evinrude website and you'll be fine. I should throw in (like any good iboats poster) that you really should get an OEM manual because it pays for itself in no time!

If it comes to replacing the impeller that is. If the motor was pumping good and just quit it does sound like there's some trash stuck in there. After I replaced my last impeller it still wasn't pumping very well out of the telltale so I just started sticking a little piece of wire up it and it improved somewhat. Still not satisfied I tracked the hose feeding the telltale back to the block where there was a little plastic 90 degree fitting. I pulled the hose off of it and started it up. Once running I worked the wire around in the fitting and it starting gushing like Old Faithful. I never saw anything come out that was blocking it but obviously there was something in there. Pull all the simple hoses and fittings you can get to and make sure they're clear and start it again. Basically what your mechanic said. With any luck at all you'll be set. If not come back and there's plenty of knowledge out here to work you through it.

Good luck!

 

[ajohnson035]

Re: 1985 Johnson 25HP Not pumping water

Thank you for your help with this. I will give it a try.

 

[Mas]

Re: 1985 Johnson 25HP Not pumping water

Is the motor overheating? If so, you've got an impeller or obstruction issue. If not, your tell tale is likely plugged.

Even so, if you do not know when the last time the impeller was replaced, now is the time! They should be replaced about every three years.

MAS

 

[kenmyfam]

Re: 1985 Johnson 25HP Not pumping water

Checking head temperature will help you evaluate if it is a tell tale issue or a motor cooling issue. Having said that don't let it overheat !!!

 

[Milemaker13]

Re: 1985 Johnson 25HP Not pumping water

Did the dealer say that they replaced the impeller? Or was it sold to you "as is" with no service having been performed?

 

[Marvxyz2]

Re: 1985 Johnson 25HP Not pumping water

Off the wall suggestion :: make sure your water level in the barrel is high enough! too low level will cause the water not to pump.