58 Super Seahorse not pumping water

[TLanglitz]

1958 Johnson Super Seahorse 35hp RDSL-20<br /><br />I've gone over this motor, including installing a new impeller and water pump housing. I just pulled the thermostat and tested it in a pot of hot water with a meat thermometer ... it works perfectly. I then left the thermostat cover off and started the motor briefly to watch for water being pumped ... There wasn't a drop. Not even a drop. The intake screen was clogged looking when I started this poject, so I poked a bunch of holes in it. I guess that could still be a problem. Before I pull this lower unit again, is there anything else that might be causing this problem? I still need to adjust the carburator, and fix a small leak in that, but the motor fires up first time, every time and runs great for the short periods I've let it run.<br />Thanks for any suggestions<br />Tom

 

[TLanglitz]

Re: 58 Super Seahorse not pumping water

I guess I posted too soon. I just started it up again with the thermostat cover off. It pumped water like a water hose that time. Phew... I really didn't want to pull the lower unit again. I have a feeling that screen is still a problem. Since the motor has been down in the barrel of water, I think the water seeped in enough for the pump to pick it up and start working. Does that sound reasonable?

 

[Paul Moir]

Re: 58 Super Seahorse not pumping water

Could be, but don't forget the pump can also suck water in through the holes in the cover just above the cavitation/anti-ventilation plate on one side of the lower unit.<br /><br />Was the waterpump submerged when you started it? Could there have been something clogging up the cooling system that blew through?

 

[TLanglitz]

Re: 58 Super Seahorse not pumping water

Hi Paul ... The pump was submerged and since it's been working I've had the motor running quite a bit while adjusting the low speed needle. I suppose it's possible that something was clogging the cooling system. When it finally started pumping while I had the thermostat cover off, it was blowing out pretty impressively. I wouldn't have noticed if a blockage was blown out with all of that water. The screen doesn't seem to be a problem so a blockage makes the most sense at this point. One thing is for sure, there is no problem with it now. I'm soaked from walking around the back of the motor. <br />Thanks for the response once again<br />Tom

 

[rolmops]

Re: 58 Super Seahorse not pumping water

Maybe the first tme you tried the actual pump was not below water level.

 

[TLanglitz]

Re: 58 Super Seahorse not pumping water

Originally posted by rolmops:<br /> Maybe the first tme you tried the actual pump was not below water level.

It was in the same barrel and the barrel was filled to the top.