Hey Everyone,This is an awesome site! I've gotten ahold of an SD20 Sea horse.The usual paint faded,cobweb covered,barn relic.I got it on the stand in the garage and pulled the plugs.A squirt of oil in each hole to loosen it up and initial compression read 90 pounds on each.(This was with my 20 dollar guage)I checked for spark and only had the upper plug firing.Well ,off comes the flywheel and I was expecting a standard set of breaker points,wow those are strange looking things.Anyway,I tightened up a few connections and re-assembled it and whadda ya know?-spark on both holes!!Moving to the carburetor,I took the the glass bowl off,removed the screen above it,blasted everything with spray carb cleaner,pulled the mixture valve and squirted it.I pulled the plugs for the lower and filled it up.(90 weight hypoid)I figured this was enough for the moment and pulled her a few times to loosen her up a bit more.Now I have to get some fuel into it.My question is the two line,pressurized tanks.Are there any alternatives or ways around not having to use a pressure tank? Will gravity feed directly into the bowl work? Can a standard tank be adapted somehow? The thing is I'm not sure what to do with this motor- to keep it or sell it.Before I throw alot of hard-earned coins at it I'd like to get it started.I checked my library for OMC manuals-no luck.Anyone wanna' throw some input or feedback around? Ooops almost forgot.Are the water pumps on these engines driven off the prop shaft?I remember reading a previous post that said the '49 and 50'Johnson outboards had pumps that worked on an eccentric off the prop shaft? Yes,no? I should get a manual.Thanks,Everyone,C.C.
I don't know much about that engine, so I can't say much for the water pump. But you can get around the pressure tank by jury-rigging a single line tank for testing purposes. Block off the pressure pulse line by taking the hose off the connector and plugging it with a drill bit (or some such thing). Then connect your single line directly to the carb's fuel line. You may need a little brass hose connector or some such thing for this. Then fill the carb up with the primer.You can just keep pumping the primer while testing it, or you can set it up higher than the motor so the gasoline gravity feeds it. You should only need to be 1 or 2 feet over the outboard for it to work.There's some info (Click here) on the SD-10. I don't know if it's very similair to yours though.
Commander Paul you are the man.I was looking at that pulse/air line and was thinking of plugging it for a test run.I'll gravity some fuel into it.24 to 1,right?I think it should fire up without to much ado.(I should dissassemble/clean carb)I really don't know what to do with this engine.I would like to get it running but,I really don't have any cash to throw into it.I will definetley make a fair offer on the 85 'Rude,I guess I'll put the SD20 on hold for a bit and see if I stumble over the proper tank for it.Thanks,Paul.C.C.