12 hp sea king oil ratio and carb settings

[unior]

I've been running 50:1 in my late 50's to early 60's sea king outboard. It is tuned ok and runs fairly well. Should I be running 24:1?

 

[tmcalavy]

Re: 12 hp sea king oil ratio and carb settings

Yes...OMC switched to 50:1 in the mid-60s, somewhere around 64...your motor is not engineered for that mixture. Use 16:1 or 24:1 using modern TCW-3 marine oil.

 

[JB]

Re: 12 hp sea king oil ratio and carb settings

Run 16:1 until you have the model number, so we can determine the exact year and suggest the correct ratio.

 

[soggy_feet]

Re: 12 hp sea king oil ratio and carb settings

Oil mix has less to do with motor engineering and more to do with oil technology. What is available today is leaps ahead of what was available in the 50's, which is why you can run less of it.
BUT, if you're unsure, its better to start rich until you're comfortable with it.

Of course, if you're running 16:1, you're running a rich oil mix, but you're running a lean air/fuel mix, so keep in mind that it may run like crap until its retuned/rejetted. Also, carry extra sparkplugs, and maybe go a heat range hotter. You'll most likely foul plugs.

 

[F_R]

Re: 12 hp sea king oil ratio and carb settings

Your Gale built 12hp Sea King has silver plated connecting rods. The silver plating is the bearing, only a thousandth of an inch or so thick. When it is gone, it is gone.

The correct mix is 24:1. Believe it.

 

[unior]

Re: 12 hp sea king oil ratio and carb settings

I'll retune and run 24:1. I know the tolerances weren't as tight back then either. It's a montgomery ward engine. Where can I find shear pins for this thing? I've been using cut off brass bolts but a pin would be stronger. Also where can I buy an impeller for this beast?

 

[unior]

Re: 12 hp sea king oil ratio and carb settings

I'll retune and run 24:1. I know the tolerances weren't as tight back then either. It's a montgomery ward engine. Where can I find shear pins for this thing? I've been using cut off brass bolts but a pin would be stronger. Also where can I buy an impeller for this beast?

The model number is GG9016C

 

[F_R]

Re: 12 hp sea king oil ratio and carb settings

Impeller right here at iboats. Same one as for 18hp Johnsons and Evinrudes.

Drive pins are stainless steel and available from any Evinrude dealer. Also same as J/E 18hp. Part number 307949.

 

[unior]

Re: 12 hp sea king oil ratio and carb settings

Impeller right here at iboats. Same one as for 18hp Johnsons and Evinrudes.

Drive pins are stainless steel and available from any Evinrude dealer. Also same as J/E 18hp. Part number 307949.

Ok. So is the drive pin designed to shear off in the event of a propeller/rock incident? If not I'll stick with my brass bolts. I can replace the pin in 2 minutes on the water. I value my lower unit and prop too much.