Johnson 5hp info needed.

[NW Redneck]

Just picked up a Johnson 5hp (1968?) Been in a basement for who knows how many years and looks in verry good condition. Has spark and compression. Going to pull the carb next weekend and clean it up and see if she runs.

I've never worked on an o/b this old before and am looking for any info y'all might have.
M/N LD-13B, S/N C578116.

So far all I've been able to find is the oil mix should be 50:1. This baby has NO gearshift on it! It looks like you get either forwards or off. Is/was this normal on older small o/b's? It also has an idle mixture knob. Where should this be set? Anyone have an owners/shop manual for one of these? Thanks in advance!

 

[Joe Reeves]

Re: Johnson 5hp info needed.

Turning the engine 180° gives you reverse.

 

[NW Redneck]

Re: Johnson 5hp info needed.

Thanks for the reply Joe! I thought that might be the case. But no neutral? I checked to see if it had a slip-type clutch by blocking the prop and trying to turn it over but no go. So I guess you warm up by putting slowly away from the dock? I'm assuming that to shut it off you just move the throttle lever all the way down as there is no kill switch?

 

[Paul Moir]

Re: Johnson 5hp info needed.

No, no slip clutch on that one. Start and you go.

I warm up my direct drive 3hp while it's still tied to the dock. At lower RPMs these engines hardly put out enough thrust to matter. Sometimes I just hang onto the dock with one hand. You also get used to not using reverse much. A long fuel line helps.

Throttle down to stop the engine. Very simple, but reliable.

1968 is correct. Check out the oil mix FAQ in the FAQ forum. You'll want a fresh impeller for it as it hasn't run in a few years.

 

[NW Redneck]

Re: Johnson 5hp info needed.

Thanks for the confirmation Paul. As I mentioned, I've never worked on an o/b this old so am a little unsure on things since I have no manual to go by. I got the oil mix from the FAQ. Post '64 should be 50:1. Is it advisable to go to 40:1 just as an extra safety margin? If so, should I change to a hotter plug? Not sure what's in it right now as it is at my in-law's place. Any recomendations?

 

[F_R]

Re: Johnson 5hp info needed.

Use 50:1 and don't be worrying about it. Today's spark plugs would be J6C. The 5 was a quality-built competetive motor againt the cheapo Sears and other stuff. Hence, no neutral or reverse gears. Why don't you give it a try before tearing into the carb? You may get lucky if the gas was drained before putting it away. The gas tank may be another story, especially if it has old gas in it. You can tell by the smell-old gas STINKS.
Don't trust the water pump impeller, replace it.

 

[NW Redneck]

Re: Johnson 5hp info needed.

FR- Thanks for the tips. Are those champion plugs or NGK? I might just try to fire it before I pull the carb. Who knows, even I'VE got to get lucky once in a while! lol The tank is dry (short 2.5 gal cruise-a-day) and has 2 nice long hoses for it. Should be able to spin it around twice! I will replace the impeller before taking it on the water.

Does anyone have an exploded parts diagram for this motor? I think I can get away with just that to change the impeller for now until I can get a manual. Unless there are torque specs that are critical?

Thanks again!

 

[Paul Moir]

Re: Johnson 5hp info needed.

Go here for parts diagrams:
<a href=http://epc.brp.com/default.aspx?brands=ej&lang=e> Click here </a>

Champion spark plugs indeed. The old J6J is no longer available but the J6C is virtually identical. Watch out, the NGK recommended plug is too hot. Actually, the Champion book's plug is too hot so don't get it either (J8C).

A service manual will be an asset for tuneup, etc, but you can really do the impeller without one if you're good with mechanics. No shift linkage or anything to mess with on that guy.

I find I want to put the gas tank up nearer the bow of the boat when I'm in it alone to improve the balance & speed (if there is such a thing with the 4hp!). That makes reverse impossible though since the hose isn't long enough.

 

[NW Redneck]

Re: Johnson 5hp info needed.

Thank you very much for the link! It's exactly what I needed. Once again the great guys at iBoats come through!

Hey Tarbender, a round for the forum! My treat! 8)d