Sea Horse 2.5 hp

F

fishcatcher

Recruit
Joined
Jul 17, 2007
Messages
4
I recently purchased a Johnson Sea Horse 2.5 hp Mod. HD20 outboard (1941/1942)....a few questions: fuel gas mixture, point gap, plug gap, and do these old motors have an impellor to pump water? I just joined this forum tonight and look forward to learning about this old motor and getting ready to use..
 
samo_ott

samo_ott

Vice Admiral
Joined
Jun 18, 2006
Messages
5,125
Re: Sea Horse 2.5 hp

It's 16:1 and try aomci.org for older motors like that. They have lots more info.
 
Last edited:
JB

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: Sea Horse 2.5 hp

The HD-20s run just fine on 24:1 using modern TC-W3 oil and regular unleaded gas, Fishcatcher.

Spark plug is Champion J8J or modern replacement (J8C?), gapped at .030".

Points are set at .020".

Yes, it has a water pump and probably needs a new impeller.

Welcome to iboats. :)
 
F

fishcatcher

Recruit
Joined
Jul 17, 2007
Messages
4
Re: Sea Horse 2.5 hp

Thanks, JB....Now I have a good starting point to try and figure this old motor out and get it running..
 
samo_ott

samo_ott

Vice Admiral
Joined
Jun 18, 2006
Messages
5,125
Re: Sea Horse 2.5 hp

I have a few HD25's (they started in 1946) but have never worked on them yet. Similar engine.
 
L

Lodgepole

Petty Officer 1st Class
Joined
Aug 24, 2003
Messages
272
Re: Sea Horse 2.5 hp

I have one of these 2.5's. 1940's and it has a off center shaft that works a plunger type water pump. Not a paddle type impeller.
 
You must log in or register to reply here.
Top