1957' 18hp johnson sea horse

[turtles11756]

hello and thanks beforehand . i have an 18 hp old Johnson I've owned for forty years all original and ran great except the lower unit which was leaking after a tuneup long ago .it now has no spark after sitting on floor in garage and i liked to know where to start or should i take it to someone with experience ? thanks again for any suggestions

 

[ray 6688]

Re: 1957' 18hp johnson sea horse

Hello.
Read the FAQs section "sleeping outboards".
You will need a new impeller as the old one will have gone stiff and will not
pump water.
Connect fuel line to motor hold in kill button and turn engine over a few times to get some lube oil in there.
Remove plugs and compression test (rings may be stuck).
With plugs out check for spark-nice big juicy blue ones.
If no spark flywheel needs to come off to check points/condencers/coils,
dont forget to inspect ht leads.
If you have sparking plugs and fuel through carb it should run.
DO NOT run your engine out of water put it in a tub or trash bin.
Good luck.
Ray

 

[turtles11756]

Re: 1957' 18hp johnson sea horse

thanks ray gonna try to get it going again as i actullay paid for it with money made delivering newspapers as a kid been sitting there 42 years and with a little work i bet (hope) it starts up. i did take out the plugs and put some motor oil in chamber years ago. the paint shines like new and it weighs a ton

 

[tashasdaddy]

Re: 1957' 18hp johnson sea horse

i like to set the motor plugs up, remove spark plug, and put some marvel mystery oil in the cylinders for atleast a day. the roll the motor over and drain. before putting the plug back in. turn the flywheel by hand feeling for any rough spots.

99% you are going to have to do coils, and spark plug wires, maybe points and condensers, the impeller will have to be replaced, an probably a carb rebuild $200-250 if you do it your self.

PULLING FLYWHEEL

you need a harmonic balancer puller, you need 3 - #8 harden bolts, that fit the 3 holes in your flywheel. standard hardware store bolts will strip out, causing more problems. loosen the flywheel nut, leaving it on so it protects the thread. thread the bolts in 7/16 of an inch. then tighten the puller, adjust so it has a straight pull. now tighten the puller, rap the center bolt with a hammer, then tighten some more. you may have to let it sit over nite, and repeat in the morning. this is a compression fitting, it will eventually POP!!. do not loose the woodruff key that goes in the groove of the flywheel and the crank shaft. then installing the flywheel, it has to be totally clean, no oil, woodruff key in place. then torque the nut to the specifications for your particular motor. if you do not do this, the woodruff key with shear, and you will be repeating these steps.

 

[ray 6688]

Re: 1957' 18hp johnson sea horse

Very nice motors,I had one some years ago and gave it away to a boating
pal!
I cant believe that I gave it away......oh well.
Get the old girl running again !
It will be good for another 40 odd years.

 

[asdasc]

Re: 1957' 18hp johnson sea horse

Actually, with the new coils, it will run for the rest of your life!

I have 2 of the old 18's and love them. Very smooth and reliable.

Shopping list:
Coils 2 @ $25 ea
Points/condensors tune up kit 1 @ $18
Carb kit 1 @ $20
spark Plugs 2 @ $4
pump impeller 1 @ $12
Lower unit seal kit 1 @ $25

Throw in some lower unit lube and a fresh can of TCW-3, some WD-40 and Deep Creep, and you are good to go! All that you need to do is covered here in details, and if you have questions, just ask. Many helpful, VERY knowledgable people here!

 

[turtles11756]

Re: 1957' 18hp johnson sea horse

I'm gonna need some help thanks again. installed new plugs thinking i might get lucky and get a spark and sure enough no spark the flywheel has to come off where can i get the puller ? the coils are what makes the spark there are no magnets or anything i might have to change when i do the points condenser ? and i will need fuel tank to engine hose double line and end fittings available here ?

 

[F_R]

Re: 1957' 18hp johnson sea horse

Chances are 99.5% that the coils are shot. They always are unless they have been replaced. The magnets never go bad. Use a harmonic balancer puller as tashasdaddy said. You better hope you don't need a fuel line connector. Those things cost about a hundred bucks, new. The o-rings are replaceable. iboats has most of what you need, I'm not sure if they sell cut lengths of double hose or not (???).

 

[coolguy147]

Re: 1957' 18hp johnson sea horse

omg yes the company has many left over ones and now selling them for like a lot fo money. if u dont have one and cant find one for a cheap price its much cheaper to convert to a fuel pump

 

[turtles11756]

Re: 1957' 18hp johnson sea horse

the harmonic balancer is on i left the flywheel nut on to protect threads after it loosened with little effort tightened down pretty good yesterday and it still holds tight . how tight do i go without something besides the flywheel give ? don't want to break anything this motor is in nice shape

 

[tashasdaddy]

Re: 1957' 18hp johnson sea horse

the only thing you are putting pressure on is the flywheel. tighten it. then a smack on the center bolt, and tighten again. it will finally POP, may scare you when it does. most of the hard ones pop during the night.

 

[turtles11756]

Re: 1957' 18hp johnson sea horse

got it ! and the only part worse for wear is my left pinkie it will be OK after a cleaning and bandage. thanks i needed your help and will let let know when i get the coils and tune up kit parts done

 

[matthewssw]

Re: 1957' 18hp johnson sea horse

Can anyone tell me what the flywheel nut torque setting is on this 18 hp 1957 Sea Horse? Figured I'd ask in here, since we were already discussing pulling the flywheel off one. I have this motor but no manual handy. Thanks.

 

[jbjennings]

Re: 1957' 18hp johnson sea horse

45 ft-lbs. is the flywheel nut torque.
You might find this thread handy......it's the same ignition as your motor.
http://http://forums.iboats.com/showthread.php?t=294072

Nice motor,
JBJ