1957 Johnson 7.5 HP Motor

[Joan]

1957 Johnson Seahorse 7.5 HP motor. Trying to replace impeller in water pump cannot separate lower unit. Does anyone know how to disconnect shift linkage so I can separate lower unit. All other units worked on there was an access plate two screws and a plate this motor does not have one.

 

[Joe Reeves]

Re: 1957 Johnson 7.5 HP Motor

Remove the powerhead. The shift linkage is under it attached to the other end of the shift lever shaft.

 

[Joan]

Re: 1957 Johnson 7.5 HP Motor

Do you know how to remove the powerhead.

 

[NYT]

Re: 1957 Johnson 7.5 HP Motor

There are some screws underneath the housing the powerhead sits on.I think it's 8 screws.Remove these and the tiller linkage and fuel line and it should pop right off.

 

[NYT]

Re: 1957 Johnson 7.5 HP Motor

Oops.My instructions are for an Evinrude but a Johnson should be similar.

 

[Joan]

Re: 1957 Johnson 7.5 HP Motor

Do you know if there is a thermostat on this motor. I cannot seem to find one.

Thanks

 

[F_R]

Re: 1957 Johnson 7.5 HP Motor

Do you know if there is a thermostat on this motor. I cannot seem to find one.

Thanks

You can't find one because there isn't any.

When you get the powerhead off, you will find a carbon seal assembly on the shaft. That seal is absolutely vital to the long term health of the powerhead. Always replace the 303355 gasket and 303347 o-ring and make sure all the other stuff is in good condition and stacked properly. Failure to do so has ruined more 5.5hp and 7.5hp motors than any other cause other than possibly overheating.