Johnson Seahorse 18 - need info

[Mikewhit]

Hi,

I just bought a Johnson Seahorse 18 - copper/white color and the model/serial tag was not on it. Is there a way to tell what year the motor is? Does it need a pressurized fuel tank? What is the fuel to oil mixture? What spark plug should it use? etc...

When I remove the cowling I can see that the fuel lines run up to a sediment bowl that feeds the carburator. I can't see any numbers on the cowling, motor or transom mount.

Any help would be appriciated.

Mike

 

[Paul Moir]

Re: Johnson Seahorse 18 - need info

Is it a metal shell hood or fiberglass? Reddish in colour? What parts are white and what parts are copper?

Pressure tank setups have a fuel connector with three shiny prongs, with two hoses hooked up to it. If it's a metal shell hood then it's probably needing a pressure tank unless it's been converted to a fuel pump.

Check for a metal convex plug pressed into the engine block down at the spark plug end. About the size of a quarter with numbers stamped into it.

 

[Mikewhit]

Re: Johnson Seahorse 18 - need info

Is it a metal shell hood or fiberglass? Reddish in colour? What parts are white and what parts are copper?

Pressure tank setups have a fuel connector with three shiny prongs, with two hoses hooked up to it. If it's a metal shell hood then it's probably needing a pressure tank unless it's been converted to a fuel pump.

Check for a metal convex plug pressed into the engine block down at the spark plug end. About the size of a quarter with numbers stamped into it.

The cover is metal and the whole motor is a copper color exept for the very top of the cover and the strip around the cover. I found the plug you where talking about and it has 1531296 stamped in to it. I didn't see a fuel pump, but am not sure what it would look like though.

thanks,
Mike

 

[BoatBuoy]

Re: Johnson Seahorse 18 - need info

You've described a '57 model FD-11(FDL if long shaft, FDE if elec. start) and yes, it needs a 2-line pressurized tank. Fuel mix is 24:1, 87 octane gas to TC-W3 outboard oil. Plug should be Champion J4C gapped at .030.

 

[Mikewhit]

Re: Johnson Seahorse 18 - need info

Thank you !!