Re: 1966 johnson model-fd20
Number one - if you're running it in a barrel make sure the water level is at LEAST two inches above the cavitation plate. Lots of folks don't set the motor down far enough in the barrel and the water pump just don't prime. It spins and sucks air. This also wrecks your nice new impeller in about 30 seconds because of the friction heat generated by the rubber fins rubbing in the houseing without any water to cool and lubricate. If this is not the problem, then you may not have gotten the water tube back into its grommet when you put the lower unit back on. Or there may be obstructions in the water passages (like chunks of old broken up impeller rubber). Whatever is up my next step would be to take the thermostat cover off, take the thermostat out, start the motor, and see if you have water shooting out (you should). The thermostat cover is on top of the cylinder head. Look the thermostat and its seal over good while you have it out. If you don't get water gooshing out with the tstat cover off then the water pump is not getting water up the water tube and into the powerhead area. Time to drop the lower unit and try again. Post back with results either way - we love to know how things turn out.
