Johnson 4 HP Seahorse Info?

[AlaskaSailor]

I have an undocumented Johnson 4 HP Seahorse, Model Number J4BRHCOB and Serial Number B102570. What year was this made? A sticker on the engine indicates a 100/1 gas to oil ratio. Is this correct? What type of oil should I mix and are there any cautions regarding grade of fuel? Where can I find a manual for this engine?

Many Thanks for your help.

 

[Vic.S]

Re: Johnson 4 HP Seahorse Info?

J = Johnson
4 = 4hp
BR = European (made in Belgium?) ropestart
H = Remote fuel tank
CO = 1985
B has no significance

it is a standard shaft (15") model

Despite the sticker saying 100:1 it should be run on a 50:1 (2%) fuel mix.

OMC had a brief flirtation with 100:1 mixes in the 1980s starting in 1985 but realised it was a mistake and issued service bulletins to say they should infact be run on 50:1 shortly afterwards. You should remove the decal and amend the owners manual to reflect that. The correct oil is a 2 stroke outboard oil to TCW3 specification.

Plugs should be L86C, or RL86C for a suppressed plug, gapped at 0.030" There is no need to fit the inductively suppressed, and much more expensive, QL86C as this engine has points ignition not CD.

Maybe get a manual from iboats or from Ken Cook or Marineengine.com