1960-70 Johnson Seahorse 10

jrcrote

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I have a Johnson Seahorse 10 not sure what year but it has a fuel knob connected to the carb and not sure how to use the knobs or how to start the motor. also not sure what ratio gas to use?? Motor has compression and spark... any suggestions?
 

Paul Moir

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Re: 1960-70 Johnson Seahorse 10

Welcome to Iboats!<br />We need a model number off the ID tag. Should be QD-nn. 10hp engines were made '51-'64 and there are some differences. The '64 is 50:1 fuel mix but all others are 24:1.<br /><br />The starting procedure is the same as any other outboard. Set the engine in a body of water as off the back of a boat or in a barrel with water up over the bolted seam between the middle of the outboard and the part that the propeller is attached to. Open the tank and pump up the primer bulb, or in the case of a pressure tank close the tank vent and pump the primer knob on the tank. Set the throttle to start (appx 1/3rd of a turn) Then pull the choke knob to close the choke. Then pull the pull start cord firmly a couple times. If the engine chugs and dies, push the choke back in and pull a couple more times until it catches. If the engine chugs and you're quick, push the choke back in and keep running. Lower the RPMs to idle. <br /><br />Here's how the fuel mixture control knob(s) are set:<br /> http://forums.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=28;t=030558
 

jrcrote

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Re: 1960-70 Johnson Seahorse 10

The model number off my motor is a QD-21 Not sure of the year? What are the knobs for in the middle by the pull start?
 

WillyBWright

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Re: 1960-70 Johnson Seahorse 10

1960.<br /><br />Top knob is your idle mixture, about 1 turn out. Bottom is for high speed, 1/2 to 3/4 turn. You'll probably need to loosen and slide the knobs out (then snug back up) to carefully turn the needles in until they lightly seat, then back them out and remount the knobs to the middle number. That should get you in the ballpark and give you room for fine tuning. If carburetion is unfamiliar to you, you're going to learn. ;)
 

BoatBuoy

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Re: 1960-70 Johnson Seahorse 10

Originally posted by Paul Moir:<br /> If the engine chugs and dies
I've been looking for the exact word to describe that, but until now I haven't found the right one. "chugs and dies", I like that. Used to do a bit of chugging myself, but I never died. Wife said I did get obnoxious though.
 

jrcrote

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Re: 1960-70 Johnson Seahorse 10

So fuel mixture should be 24:1? and turn the knobs all the way tight and the top knob 1 turn and the bigger bottom knob set tight and put the knob to the number to the right and turn half way threw the numbers? I will try it!
 

jrcrote

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Re: 1960-70 Johnson Seahorse 10

I also got a metal gas tank with it... Is it a pressureized tank or can i use my plastic tank from my 98 johnson motor?
 

tashasdaddy

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Re: 1960-70 Johnson Seahorse 10

if the new fitting fits, use it, but your fuel mix is different between the engines. 1 quart oil to 6 gal gas for the 10 horse, 1 pint oil for the 98 motor.
 

jrcrote

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Re: 1960-70 Johnson Seahorse 10

I got the motor to fire! It just won't stay running. has spark and i think i have the knobs right.. any suggestions?
 

tashasdaddy

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Re: 1960-70 Johnson Seahorse 10

probably needs carbs taken apart, soaked overnight, blown out with compressed air, and a rebuild kit. could need fuel pump. if this motor has not been run in a while use the red search function and search "awakening a sleeping outboard" welcome to iboats.
 

jrcrote

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Re: 1960-70 Johnson Seahorse 10

I got it to idle for about 10 seconds but i will try cleaning the carb~ thanks!
 

jrcrote

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Re: 1960-70 Johnson Seahorse 10

If I do get this motor running how much is it worth?
 

WillyBWright

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Re: 1960-70 Johnson Seahorse 10

If you try to use your plastic tank, make sure your life insurance is paid up. Your widow's gonnna need it. ;)
 

Paul Moir

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Re: 1960-70 Johnson Seahorse 10

1960 ought to have a fuel pump and single line tank. No worries.
 

jrcrote

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Re: 1960-70 Johnson Seahorse 10

yeah it has a fuel pump on the side. took the carb apart looks clean and the bowl too.. still can't get it to run more then 10 sec. It has spark but i think i am gonna get new plugs. not sure if the plugs are right that are in there anyone know what model plug to get?
 

Paul Moir

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Re: 1960-70 Johnson Seahorse 10

Try pumping the primer bulb and see if you can't keep it running. Perhaps there's an air leak in the fuel line.<br /><br />Plugs are Champion J4C (replaces J4J) gapped at .030". But I doubt that's your problem, not if it only runs for 10 seconds.<br /><br />Unless you can see up into the minuscule idle passages, you can't confirm that the carb is clean. Hold it suspect.<br /><br />Good spark is one that will jump 3/8". The most common ignition problem with these engines will allow the spark to jump .030" just fine, but not 3/8".
 

tashasdaddy

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Re: 1960-70 Johnson Seahorse 10

did you just take carb apart or did you due a through cleaning, and rebuild kit?
 

jrcrote

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Re: 1960-70 Johnson Seahorse 10

How much does a rebuild kit cost and where do I get one?
 

Paul Moir

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Re: 1960-70 Johnson Seahorse 10

$20-$25, get the dealer one (from a J/E dealer) since it comes with a new float. Iboats carries the aftermarket one but no float.
 

jrcrote

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Re: 1960-70 Johnson Seahorse 10

If I get this running how much would this motor be worth?
 
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