1980 70hp seahorse bad idle

alyakhim

Recruit
Joined
Apr 13, 2009
Messages
4
Hi All,

I've recently purchased a 1980 bluefin w/ a 1980 70 hp johnson outboard. The motor runs like a top however it seems to load up when running at an idle, it will only start loading up after it has been idling for a while (when I troll with it). It also has a lot of hesitation when throttling up and it will sometimes die when throttled up to quickly, if i throttle it up slowly the motor will catch up and run like a champion. I assume that it is a carburetor issue however I'm not familiar with this type of outboard engine as there aren't any jet adjustment screws, I assume that this motor has fixed jets? If you guys can steer me in the right direction it would be greatly appreciated, thank you.
 

jonesg

Admiral
Joined
Feb 22, 2008
Messages
7,198
Re: 1980 70hp seahorse bad idle

How much oil are you running?
Are you using Champion plugs?
What are the plugs gapped at?
Wider gap for extended trolling prevents fouling of plugs.
 

alyakhim

Recruit
Joined
Apr 13, 2009
Messages
4
Re: 1980 70hp seahorse bad idle

50:1
Plugs are champion
I am not sure of the gap, what gap do you recommend for trolling?
 
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