1954 Johnson Seahorse qd-15 10HP

[coalkracker]

Hi everyone! I'm new to this forum and also new at owning an outboard. A few days ago I purchased a 1954 seahorse 10hp. Supposedly it's just been completely serviced with a carb rebuild, new coils and plugs. I paid 150 for the motor and tank which I think was a decent deal. The only problem is never owning one before I don't know how to run them. Any help at all would be greatly appreciated! Does anyone know what fuel mixture I use? And also there are two knobs, I beleive they are low adjust and high adjust. I can use some help with those also. Thank you in advance!

 

[coalkracker]

Here are some pics of it...

 

[racerone]

Looks like it has suffered from a severe overheat too.-------The mixture is 24:1-----The lower needle is the high speed air / fuel mixture adjustment.-------The upper one is the idle fuel mixture adjustment.----------Lower is 3/4 turn from gently seated.----Upper is 1 1/2 turn from seated.------The motor should start and run with those settings.-----It must then be adjusted for best running by the operator when motor is on a boat.--------It would be in your best interest to research setting those mixture needles.

 

[64osby]

Welcome to the site.:welcome:​

Sounds like a good deal.

24/1 should be the fuel mixture.

Others should chime in with the proper low and high settings.

I have a 10 hp from 56 and 58. Easy to work on and have been nice runners for me.

Have fun.

 

[coalkracker]

Great thank you! Any specific kind of oil for these older motors or just regular marine 2 cycle? And what makes you think it has overheated in the past?

 

[hardwater fisherman]

I think he said it was overheated because if you look at paint on the cylinder head it looks scorched. Any marine grade 2 stroke oil should be ok. If the previous owner did a tuneup did he not set up the carb? If it starts and runs well there is no need to touch those adjustment knobs.

 

[coalkracker]

Ohh that's not scorched, it's only oil with dirt stuck to it...i haven't cleaned it yet since I bought it, I'm actually going to use degreaser on it in a few minutes. And yes the carb is set and it runs, I just didn't really know what the knobs were for. I'm a newbie when it comes to outboard motors, this is my first one. I bought it to restore and use on a large lake near my house.

 

[F_R]

Looks like burnt paint from where I sit.

 

[boobie]

Me too......

 

[Crosbyman]

http://boatinfo.no/lib/johnson/manuals/1922-1964johnson.html#/0

 

[coalkracker]

Thank you for posting a link for the manual. Another question I have is what fuel should I be running? Do I run a higher octane or will regular be alright? I use premium in my chainsaw and weedeater but they are much newer, I don't want to hurt anything on this motor by making a stuipid mistake. I also use a little bit of marvel mystery oil in all of my yard equipment, is it ok to be using it for this also?

 

[kbait]

You only see a benefit from higher octane with higher compression performance-type motors. Non-ethanol is best, if available in your area. Ethanol=alcohol, alcohol absorbs water over time, and you end up w/water in the bottom of your tank. Ethanol also degrades gaskets, fuel lines, fuel pump diaphragms.. if they're not ethanol resistant. Mystery oil won't hurt, and helps reduce carbon buildup..
Good luck!

 

[HighTrim]

If the motor starts, idles, and runs out well, I would leave the needles alone. Most guys set the knobs, after they are setting, pointing at one another, so that they know if they have been moved at all, or bumped.

For you knowledge though, to set them:

Start with high speed. Go WOT, full speed. Try for a calm day, and beware of other boaters. Start with needle 3/4 out from seated. Slowly, giving the motor time to respond, turn the needle clockwise, or lean, in small increments. When it starts to bog, or die, back it out 1/4 turn.

Then go down to an idle. Again, but with the low speed needle now, turn in small increments, giving motor time to respond, clockwise, until it starts to sneeze. Then run back 1/4 turn. Initial settting on this is 1 1/2 turns out from seated as mentioned.

Then, take off knobs, and re attach with them facing each other. This is simply to know if they have been moved.

 

[oldboat1]

If you find that the needles have moved and your kid denies everything, suspect the jam/gland nuts at the base of the needles. After getting it dialed in, I like to go back and snug up the nuts just to make sure the needles don't rattle loose -- snug enough to hold the needles in place, but not so tight you can't make adjustments.