Rich and lean dial settings on a 5.5 johnson

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JamesM56alum

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K so i have a 60's or 70's johnson seahorse 5.5 and i have no clue how to use the dial settings for the lean/rich i'v never touched them really i'd just like to know what setting's they would be on and what they'er for. It says Fast/SLow Rich/Lean with a small dial inside a bigger dial. :shock:
 
rich is a term used to describe more fuel, lean is less fuel. if a motor is running lean it needs more fuel and you would turn the knob to the rich side. if the motor has too much fuel it would be considered rich, you would turn the knob to the lean side.

the fast one is the adjustment for when you are traveling full speed and the slow one is for when the motor is idling.

do adjustments on the water. try tightening the knobs (to the right) towards lean, all the way and back off 1 1/4 turn. you will notice the motor will die out for a second but will continue to run, this is known as a lean sneeze. when you have backed off the knob enough the sneeze will disappear. after the sneeze is gone, back off an additional 1/4 turn. this should be the new center adjustment, pop the knob out and reset to center, you can fine tune from there up or down.

you will need to adjust idle during this procedure as well. adding or taking away fuel will change the initial idle setting. as you are making lean/rich adjustments keep adjusting idle to keep it at a desired rpm.
 
You need to know what year that engine is. It makes a difference on whether is has to be run on 24:1 or 50:1 fuel/oil mixture. Anything prior to 1964 must be run on 24:1 due to the fact it is a plain bearing engine. If the engine is a green or reddish engine it must be run on 24:1.
 
x3 and you will notice that that when running WOT the smallest tweak in the fast adjustment will make a world of difference in the running. Just play with it a lil using gps until you get optimum performance.
 
I agree with Pappy, let's confirm the engine before running it. Fuel mix is critical.
I grabbed a couple pics from your other thread.
The model number should be on the top or side of the transom clamp.
 

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bbstacker1 said:
Based on the original post and the pictures, that should be a 59 or 60 model.

Yea, I was thinking the same when I saw the two line gas tank.

edit:
guess what I found on craigslist...
 

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Nice jasper too bad it wasnt a 9.9 i'd freaking jump on it!!!! LOL

i'm thinking the mix should be 50.1 ?

here's a better pic of mine.


100_0487.jpg
 
James, that motor hood looks just like a QD-21 (10hp) that I have, except for color. I believe they only used that cowling on three years, 59, 60 and 61, the 61 did not have the rings on top. Aging your engine by that, you should use 24:1 ratio in that motor (if you like it) not 50:1
 
Based on the webshots I have looked at and the lack of information on the engine it looks like a 1960 model

https://rides.webshots.com/photo/2052156700101354590ZFOEiM

Based on this alone the engine should be run on a 24:1 mixture.

Many other procedures should be adhered to in order to properly bring this vintage engine back into service including a full ignition, water pump and cursory carb service.
 
Hi, I see this post is a couple years old but I recently acquired the same 1959 Johnson Seahorse 5-1/2 HP. The model number is a CD-16.
The guy I bought it from insisted on a 16:1 gas/oil mix and I have done that. However, it smokes ALOT. What did you end up using for your's? Also, what settings are you using for the rich/lean?

Thanks,

JoeIMG_20140720_133234.jpg
 
16:1 is where I would run it; however, others will tell you 24:1.

The needles on the carb should be initially set (gently seat then open):
high speed - 3/4-1 turn open
low speed - around 1.5 turns

tune the carb from there.
 
If originally a pressure tank, 2line, it is a 1959. If it has a fuel pump originally, it is a 1960 or later. In any event, the 5 1/2 is a plain bearing engine.

These are some things I keep in mind when mixing a tank of fuel:

*Modern TCW-3 oils no longer require 24:1. The recommended mixture changed in 1964, but the engine specs did not.
*Never use chainsaw oil in an outboard. Air cooled oils are different from water cooled oils.
*Add extra oil for a plain-bearing applications.
*16:1 will fog the lake for mosquitoes. Use only for antique chainsaws...maybe.
*Many Johnson/Evinrudes were labeled 100:1 during the 80s. I NEVER do that.
*With modern TCW-3 oils, especially synthetics, 50:1 works just about anywhere.
*Double oil, 24:1, is recommended in most operators manuals for continuous-full-throttle or 'racing' usage.
*Keep your eyes on what you're doing. Never mind the girl in the red sportscar.

Mark any fuel container with the fuel inside as soon as you mix it. I use combinations of white and black wire ties to mark tanks. White is raw gas, black is 50:1, 2 black ones for double oil...etc. Buy cheap, weak, wire ties that are easy to break off. They are just reminders.
 
The fact that todays oils are different and "better" does not indicate the ability of that oil to protect a plain bearing engine at half the recommended oil required for said engine.
You are looking at the girl in the red bikini !!
Lots of things in the old engines were and still are different including piston materials, number of rings per piston, ring material, thickness and tension, bearing materials, bearings design and overall clearances for a few. They were all pretty primitive back then compared to today...never assume they can take what todays materials can or that their clearances were set up for half the oil. That can be an expensive statement to make specially when you make that recommendation for another man's engine!
Based on this the only safe statement to make is to follow the engine manufacturers recommendations on fuel/oil ratios. Always THE safe statement to make.
Why waste a great vintage engine that parts are not readily available for when it does not have to happen.
As far as newer engines go.......or older engines for that matter.....
Engines will seal better on more oil.
Engines will develop more horsepower on more oil
Engines will be better protected during an overheat on more oil
Oil is cheap compared to powerheads and having to paddle back or be towed !
Now where is that girl again?

As far as the OMC 100:1 engines go....(another marketing based decision) there was a dealer bulletin that came out shortly afterward that indicated those engines were to be run at 50:1 and that the stickers were to be pulled off. Never happened but the bulletin happened at least. Some engines that were run on 100:1 did not have enough lubrication to survive the seasonal down time depending on where they were stored and were stuck by the following boating season, hence the bulletin.
Even the synthetics had their issues with seasonal down time. At one point OMC ran their European racing schedule with engines run only on synthetic oils. The ratios were the same. By the time the following race season started those engines were stuck solid as well forcing tear downs on each and every engine. The synthetics at that point in time did not stay in place like the dino based or paraffin based oils did.
 
Some is good, more is better, and too much is just right...Right?.

Too much oil builds up carbon. Carbon sticks rings and promotes detonation. Oil reduces octane of the mixed fuel. A glowing hot carbon deposit can light the fuel charge before the spark plug.

Carbon sticks rings. A stuck ring can't float to maintain seal with the cylinder wall. Hot combustion gasses slip past the stuck ring burning the ring lands, piston crown, and skirt. These combustion gasses burn the lubricating oil film off the cylinder wall too. Pistons that overheat grow in size and start grabbing the cylinder wall. Piston melt and wall scuffing can occur quickly.

Oil mixture ratios need to be balanced with common sense. MUCH testing has been done by many groups of engineers to determine the best oils and ratios to use. An engine that idles all day will run forever on 100:1. Most factory recommendations for recreational conditions are 50:1. Owners manuals often note that double oil, 24:1, should be used under sustained full throttle operation(racing). It's in there I read it.

I haven't seen 16:1 recommended by ANY manufacturer in my memory.

I know of someone who mixed 1 quart to 1 gal. He complained the engine wouldn't even run right...figure that.

Dumping gobs of extra oil into your tank doesn't do your engine any favors. If you feel a NEED to over oil an engine, make sure to de-carbon the thing once in a while.

Winterize:
*My special winterizing mix is around 8:1 with avgas and some OMC fuel conditioner.
*Run the warm engine out dry.
*While still warm, squeeze bulb the engine full of Special Mix.
*Disconnect the fuel line and start 'er up.
*Let it run out of that fuel.
*Choke it to death at the very end to pull all the fuel out of the bowl.


Gotta go with Pappy on this: Let the final word be the people that designed and built your engine. If your going to deviate from that, then be reasonable and use common sense.

Some is good, more is not always better, and too much is never right.
 

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