Help with 1960 Johnson 18hp Seahorse

[bwkre]

Re: Help with 1960 Johnson 18hp Seahorse

Glad to hear you got it running. Hope everything goes well on your trip.

My boat & motors are sleepin too. Probably till the end of May. :blue:

 

[Zapit2um]

Re: Help with 1960 Johnson 18hp Seahorse

Back from the river and she ran like a champ! 20 mph 2 guys and 4 dozen decoys.. even faster than when it crapped out on me. My boat sees more action during the winter than during the sumer. :lol: I take it out every weekend both days during the season so it get's quite a workout. Thanks again everyone!! I've learned a lot over these past few days!

 

[Zapit2um]

Re: Help with 1960 Johnson 18hp Seahorse

Let's talk spark plugs.. The plugs that came with the motor are J8C's, I have read several articles that say J6C's are what should be installed in this particular motor. Is that so? What will the J8C's do to my motor, it seems to run just fine with them.

 

[kbait]

Re: Help with 1960 Johnson 18hp Seahorse

Motor spec's J4C's, You could run J6C's gapped to .030" if extended trolling/low speed to avoid fouling 'em.

 

[HighTrim]

Re: Help with 1960 Johnson 18hp Seahorse

Either the J4Cs or the J6Cs, I prefer the J6C's as an all around good plug in all of my 50s OMCS.

I would take the J8s out.

 

[kfa4303]

Re: Help with 1960 Johnson 18hp Seahorse

Glad you got her running again. 20 mph is pretty dang good for two guys and lots of gear. +1of the spark plugs. I run J6C on my '66 20 hp and they work great. I spend lots of time idling through no wake/manatee zones and I've never fouled a plug even running a richer mix than normal. I've never had an overheat after making long WOT runs either. Feel free to post some pics of your new/old fire-breather in action

 

[bwkre]

Re: Help with 1960 Johnson 18hp Seahorse

I'm running J6C in my 61 18hp Evinrude & they work great. Never had a problem but I always carry a spare set ready to go sealed in a bag with my Foodsaver. Keeps them nice and dry. The first time it skips a beat or hesitates I stop & change out the plugs. You never know when the weather could change and you get caught trying to change a fouled plug! I've yet to have it happen with my 18hp but I did get caught in the middle of the lake and a storm with my 9.9hp. A foolish mistake I'll never make again. My wife just about s**t herself. I think I'm still paying for that one.:lol:

 

[HighTrim]

Re: Help with 1960 Johnson 18hp Seahorse

bwkre, I see you are in NW Ontario.....what lake were you on?

Regarding fouling a plug, I cant for the life of me remember when the last time that happened to me was. Many years. I use synthetic oils, or XD oil from BRP, and it burns very clean.

 

[bwkre]

Re: Help with 1960 Johnson 18hp Seahorse

bwkre, I see you are in NW Ontario.....what lake were you on?

HighTrim, I was on Lake Marie Louise in Sleeping Giant Prov Park.
I have to use the 9.9 cause it is in the park. Seems at least once a season it happens. Cylinder will start cutting in and out at wot. And then if you come down off wot too fast it will die. Just change the plugs & carry on. Lets not Hijack this thread, enough said.