Owners manual Johnson Seahorse CD-15

kfa4303

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Re: Owners manual Johnson Seahorse CD-15

Hello again. 24:1 should be fine for that motor, if I'm not mistaken. Generally speaking, motors form the 30s-40s tend to run 16:1, mid50's-early to mid 60's usually run 24:1 and motors from the late 60s/early 70's run 50:1. Most of us with vintage motors tend to run a bit more oil just to be safe. Technically, mine says to run 50:1, but I run 24:1 and have never had an issue. Plus, I can always add a bit of straight fuel to it in an emergency and it will still be well within the 50:1 ratio.

24:1 is approximately 5.5 fluid oz to 1 gallon of 87 octane fuel (petrol), but I just round up to 6 oz to keep it simple. Sorry I don't know the metric conversions. What are meters again ? :)
 

JohnRudeMan

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Re: Owners manual Johnson Seahorse CD-15

Thanks. I think I'm going to run my AD-12 20:1, it's safe and simple :).

Greetings JohnRudeMan :)
 

1946Zephyr

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Re: Owners manual Johnson Seahorse CD-15

I would stay with 16:1. The 7.5's have been known for blowings rods. Leaner oil mix will just add to the probability. The decals on the motors even state 16:1 mix.
 

kfa4303

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Re: Owners manual Johnson Seahorse CD-15

Good save Zephyr. If you're at 20:1 already you'll only need to add a bit more oil to get it to 16:1 as needed. Again, always better to err on the side of caution. When in doubt, add more oil. I didn't realize they were still running 16:1 in '58. Was that true for all model, or just the AD in particular? I can't wait to see some pics.
 

TN-25

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Re: Owners manual Johnson Seahorse CD-15

You can run it at 16:1 mix and it won't hurt anything, but bear in mind that 16:1 was on straight 30-weight non detergent automotive oil. Any TCW oil made since 1964 is vastly superior and allows a leaner mixture. In 1963 the motors ran 24:1, in 1964 they were supposedly 50:1. What changed? They introduced the new TCW oil!

JohnnyRudeman, I have the same motor, a 1958 Johnson 7?. I wouldn't run mine any leaner than 24:1 on TCW-3 oil, but the buffoon I bought the motor from ran it on 50:1 :eek: He really just trolled with it, but the motor did not fail or suffer any apparent damage (luckily). Really the old motor was designed for 16:1 so run it like that if you want to play it safe. That is what I do now. These old AD-12 motors have bronze bushed bearings and a few decades of use on them, so oil rich fuel is an insurance policy. Just run synthetic oil so it smokes a bit less.

The 10-horse motors and above had needle bearings and can live on leaner oil mixtures safely.
 

1946Zephyr

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Re: Owners manual Johnson Seahorse CD-15

Yea, I have a 1954 Fleetwin 7.5 (same as your AD model) and it has survived the years really well, but then again, I'm the second owner.

Yes you're right TN-25. The 10hp and larger motors had needle bearings and were set up to run on 24:1 whereas the smaller motors all had bushings.
 

JohnRudeMan

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Re: Owners manual Johnson Seahorse CD-15

@TN-25: How can I see that the motor has damage from running it 50:1? Here in Holland is almost everbody running their motors 50:1 (even the old '50!), simply because nobody has any sense of old outboards and they don't know the old outboards must run on 16:1 or 24:1.

I hope you can understand my English :D:D
 

JohnRudeMan

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Re: Owners manual Johnson Seahorse CD-15

Is it normal that the 7.5hp Johnson's are heavier to start (heavier to pull the rope) than the 3hp Johnson's?
 

kfa4303

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Re: Owners manual Johnson Seahorse CD-15

Hello again. They may be a bit harder to start, but once properly tuned it should start in 1/2-1 pull. I was able to get my '61 10 hp to start if I so much as looked at it and thought the word "start". If you feel that it is too stiff, you can try spraying a bit of WD-40, or Deep Creep or Sea Foam into the cylinders by removing first the spark plugs and laying the motor face down. Let it sit for a while, then gently pull the motor over with the plugs still removed (be sure you disconnect the plugs from their wires as there will be a fine mist expelled from the cylinders, which could ignite if the plug should spark at the wrong time.) You should feel a nice smooth "lub-dub" motion after the lubricant has had some time to take effect. Once you get it running, it way also be worth while to run a gallon of fuel with some Sea Foam added to it to help remove carbon deposits and relubricate the engine's innards. If everyone runs engines at 50:1 as you say, your little motor may have been starved for oil for the last several years (decades?). However, these little gems are tough, and as long as you have decent compression all the rest is pretty easy to fix. Even if the compression is low, it can often times be remedies by installing a new head gasket. I'm not sure if they sell Sea Foam/Deep Creep in Europe, but it's great stuff. It's essentially pure petroleum and works wonders on any internal combustion engine from your car to your lawnmower to your vintage outboard. Here's a pic to use as a reference. Do a search here in the forum under "Sea Foam" and/or "Decarb", "Decarbonize" and you'll find lots more info. Cheers!


Sea Foam.jpgDeep Creep.jpg
 

JohnRudeMan

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Re: Owners manual Johnson Seahorse CD-15

@kfa4303: I've found a website where I can buy Sea Foam :).

Does anybody know a website where I can buy a new fuel line for my pressurized fuel tank (the two line system)?
 

kfa4303

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Re: Owners manual Johnson Seahorse CD-15

Glad you found the Sea Foam. When you use it be sure you have LOTS of ventilation it will smoke like crazy, but that's sort of the point. All of the smoke is the old carbon burning away. Here are some links that show all the various uses. It works great on cars too. I also found a link to a previous thread here in the forums regarding your fuel lines. It seems like any high quality automotive fuel line will work. They recommend taking some of the old line with you to the autoparts store to be sure you get the correct size. Glad you're making progress!

http://forums.iboats.com/showthread.php?t=86773 (fuel line thread)

http://forums.iboats.com/showthread.php?t=158076 (decarb procedure and explanation)

http://www.youtube.com/watch?v=vRAV5ln5cUc (Sea Foam How to Video)

http://www.youtube.com/watch?v=sLOuUWV4GrQ (decarb video using Deep Creep on an outboard almost identical to my own. Note the amount of smoke. That's normal, but an electric fan to blow away the exhaust is very helpful to prevent the engine from inhaling dirty exhaust.) (Don't worry. After the treatment is complete it will not smoke nearly as much. In fact, it should actually reduce smoking in the long run)

http://www.youtube.com/watch?v=g15-g9ulZic (video of a car using Sea Foam.)(All of the smoke is old carbon that is being burned away.)
 

JohnRudeMan

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Re: Owners manual Johnson Seahorse CD-15

Thank you very much for the videos :)!
How much Sea Foam (the Sea Foam for in the fuel) should I use on one gallon of gasoline?

Greetings JohnRudeMan :)
 

kfa4303

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Re: Owners manual Johnson Seahorse CD-15

One 12-16oz can to every 3/4-1 gallon is good, but you can use less. I often divide one bottle into thirds and add 1/3 to my fuel, 1/3 to the cylinders by removing the spark plugs and spraying/pouring the sea foam in after the motor has had a chance to warm up, I then use the remaining 1/3 to spray through the carb in aerosol form if I feel it is needed. One important point is to let the motor get up to full operating temperature. Ideally, you would start the engine use it a WOT for 20-30 minutes with the 1/3 bottle sea foam in normal 16:1 fuel/oil mix (it will smoke quite a bit), then shut it off lay it face down remove the spark plugs and pour the sea foam into the cylinders. Let the motor sit as long as you like. Overnight would be good, but a few hours is fine. You can then stand the motor upright and gently pull the starter rope. Any excess sea foam will be blown our of the cylinders (make sure spark plugs are removed from their wires so they don't spark and ignite the sea foam). You may also see some black ooze coming out of the exhaust. You can now replace the plugs and start the motor. Again, it will smoke A LOT. Warn your neighbors and have a fan nearby in case you need to blow the exhaust away. Once the motor is running, take it out and run it at WOT until the remaining Sea Foam fuel is used up. It will continue to smoke at first, but the longer you run at WOT, the better it will get. After you've burned through the sea foam mix, you may want to replace/clean the spark plugs as they can sometimes become fouled during this process. You can use the remaining 1/3 of Sea Foam in aerosol or spray form as needed by spraying it into the carb as the motor is at high idle.
 

JohnRudeMan

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Re: Owners manual Johnson Seahorse CD-15

Thanks for the information :)! What do you exactly mean with 'WOT'?

Greetings JohnRudeMan :)
 

TN-25

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Re: Owners manual Johnson Seahorse CD-15

Thanks for the information :)! What do you exactly mean with 'WOT'?
'WOT' is short for 'Wide Open throttle', in other words, running the motor at full speed.
 

JohnRudeMan

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Re: Owners manual Johnson Seahorse CD-15

Thanks :)! In about two weeks I'll be able to start the tune-up on my new outboard. Here in Holland it's a little bit cold for a tune-up, it's -15 degrees C :D!

Greetings JohnRudeMan :)
 

kfa4303

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Re: Owners manual Johnson Seahorse CD-15

Yikes that's cold !!!!! It was almost 80 degrees F here the yesterday :) No worries, two weeks will go by quickly enough. It will give you time to read up on your motor and all the various tune up procedures. I hope the weather warms up for you soon. Keep us posted. Cheers!
 

JohnRudeMan

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Re: Owners manual Johnson Seahorse CD-15

I'll start the tune-up next friday :).

Greetings
 
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