1956 Seahorse with impeller issues?????

[Gofiggah]

I have a 12 foot fishing boat with a 1956 Seahorse (7.5 HP). The boat had not been used nor started in over three years. I got the motor to start but it will run for about 1 minute before going into high rpm's and then shutting off. I get no water discharge from the cooling system (impeller I suppose). Even after 21 years in the Navy I am boat ignorant. I am trying to get this boat working so that I can take my stepson fishing. If I don't have to lift much I may be able to fix it myself or I may need to get information on someone in the central california area that can fix it as I have recently become disabled and can't lift very much anymore. Any information that can guide me would be greatly appreciated. Fishing is about all I have left that I can do. Thank you.

 

[lindy46]

Re: 1956 Seahorse with impeller issues?????

Two separate issues. Running and quitting sounds like a carb/fuel delivery issue. Carb probably needs cleaning and rebuilding, or could be a fuel delivery issue. Make sure the gas cap is on tight as the fuel delivery is by pressure build-up in the tank. The motor has no fuel pump. If no pressure is building up in the tank (evidenced by a "whooshing" sound when you unscrew the gas cap), the motor won't stay running.

The impeller sits in the water pump housing on top of the lower unit. You have to remove the lower unit to get to it. Lower is held on by 5 bolts and you have to remove the little oval cap on the side of the leg to get to the shift rod coupler. Completely remove the lower shift rod bolt from the coupler to free up the shift rod. With the bolts removed and the shift rod disconnected, the lower will drop right down. Once the lower is removed, there are three or four flat head bolts which hold the water pump housing on. Remove the housing and the rubber impeller is inside. When replacing the impeller, make sure the drive key is in place on the driveshaft and the impeller fin ends trail when the driveshaft is turned clockwise.

 

[lindy46]

Re: 1956 Seahorse with impeller issues?????

OOPS! Didn't see that it is a 7.5hp model. With that model, there is no shift rod coupler on the side of the leg. Unfortunately, you have to remove the powerhead on that model to get to the shift connect. A little more difficult a job. Search this site for the procedure. It has been addressed many times.