8HP Johnson cooling problem

[Peter Brown]

My J8REOD 1995 Johnson is not pumping saltwater after being unused for 6months. Dropped leg and installed new impellor and checked thats tubes to top head clear. Can anyone out there confirm what the problem might be ? My gut feel is maybe the water cooling channels in the head have clogged ? Otherwise a beautiful bit if kit that has served us well in saltwater without any problems for 14years. Peter: confused:

 

[tashasdaddy]

Re: 8HP Johnson cooling problem

clogged tale tell hose, bugs like to make nest in them, remove and blow out.

 

[Peter Brown]

Re: 8HP Johnson cooling problem

Thanks for response. Have checked and cleaned all tubes ın stern leg and ınstalled new ımpellor so thats not the problem. Blockage ıs obvıossly somewhere else and my gut feel ıs that the saltwater coolıng channels ın the head may be gunked up. Desparate to receıeve any suggestıons as to what problem mıght be as don't want to go ahead and remove the head ıf I mıght be wastıng my tıme. Peter
ps
we are cruısıng ın Turkey at the moment so may be a few days before can fınd an ınternet cafe to respond to any help messages.

 

[david_r]

Re: 8HP Johnson cooling problem

how about the thermostat?

it could be stuck........ especially if used in salt water.

 

[Daviet]

Re: 8HP Johnson cooling problem

Is water coming out of the tell-tale? The tell-tale is an indicator of the water pump operation, and not affected by the thermostat, do as tashasdaddy suggested and clean the tell-tale tube. If the tube is clean, and you still don't get any water out of the tell-tale you still have a water pump or water tube problem. If you have a good tell-tale you might try removing the thermostat and see if it cools properly.

 

[david_r]

Re: 8HP Johnson cooling problem

sorry for the wrong info.... i was thinking of my lil '64 18hp.

mine quit spitting water and i changed the water pump to no avail....... then i changed the thermostat and it started spitting water again........ i wasnt even thinking of the fact mine is old and doesnt have a tell tale.

 

[Vic.S]

Re: 8HP Johnson cooling problem

If you are getting no water from the tell tale check that is not blocked.

If that is clear then it is a pump or water-tube problem. The grommet at the top of the water tube causes problems on some but not sure if it does with a 1995 .. it sure does on a 1984 model Power head off to fix unfortunately.

Can you get a flow if you stick a garden hose on the bottom of the water tube.

If you do get a flow from the telltale but it is overheating then possibly a thermostat ("Vernatherm") problem or the waterways in the head are blocked.

Remember the telltale branches off quite early in the cooling system ... it really is just an indicator that the pump is pumping and that water is getting up to the power head. Blocked head passages wont stop water comming from the telltale!