1977 70hp Johnson gas soaking plugs and won't fire?

bigcountry29

Recruit
Joined
Nov 6, 2013
Messages
2
I recently got a 21' Carolina skiff and it has a 1977 70 hp Johnson on it.. I can't get it to start and when I pulled all the plugs and crank it it shoots a milky mixture of gas and oil out (and starting fluid. Maybe that's why it's milky?) I don't think there's water in it cause if I put some on my finger it evaporates right away.. But when I dry the plugs out and crank it the first time it wants to run but the plugs get soaked right away and it won't fire again and when I pull the plugs they're soaked.. Anyone have any ideas??
 

Daviet

Fleet Admiral
Joined
Sep 24, 2008
Messages
8,958
Re: 1977 70hp Johnson gas soaking plugs and won't fire?

Has the engine ever run properly on the plugs in the engine?
Does the engine have the proper plugs installed?
Have you checked the spark, is it bright blue and does it jump a 7/16" air gap?
 
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appleo

Petty Officer 1st Class
Joined
Jul 19, 2012
Messages
388
Re: 1977 70hp Johnson gas soaking plugs and won't fire?

Check the spark when wet
Might be a bad coil if all 3 won't fire
Check your tilt switch, temp switch and all other disablers
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
39,140
Re: 1977 70hp Johnson gas soaking plugs and won't fire?

Check if spark will jump a gap of 3/8" or more--Check flywheel key.
 
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emdsapmgr

Supreme Mariner
Joined
Dec 9, 2005
Messages
11,551
Re: 1977 70hp Johnson gas soaking plugs and won't fire?

A "milky" mixture of fuel could be signs of water. You may need to pull the head to see for sure. You could either have a bad head gasket (check your compression to validate) or the exhaust cover gasket could be leaking water into the exhaust chest. Water in the engine will prevent ignition.
 

boobie

Supreme Mariner
Joined
Nov 5, 2009
Messages
20,826
Re: 1977 70hp Johnson gas soaking plugs and won't fire?

Sounds like a water problem. Those motors had exhaust cover gasket problems.
 
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