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70hp 1985 Johnson dies and won't start back

M

mainliner61

Contributing Member
A friend has a 70HP Johnson,I think it's a 85 model.Today he started it and let it idle for about 5 minutes then it died and would'nt start back. Pulled plugs and they were wet so cleaned with carb cleaner and let dry.Tried again and would'nt even try to fire.Pulled plugs again and was wet again.I think spark has quit.Any ideas? Thanks.
 
Re: 70hp Johnson dies and won't start back

Remove spark plugs. rig a spark tester whereas you can set a 7/16" gap. The gap is important..... do not attempt to check for spark by using the spark plugs as that is a waste of time and effort. No Tester? See below.

(Spark Tester - Home Made)
(J. Reeves)

A spark tester can be made with a piece of 1x4 or 1x6, drive a few finishing nails through it, then bend the pointed ends at a right angle. You can then adjust the gap by simply twisting the nail(s). Solder a spark plug wire to one which you can connect to the spark plug boots, and a ground wire of some kind to the other to connect to the powerhead somewhere. Use small alligator clips on the other end of the wires to connect to ground and to the spark plug connector that exists inside of the rubber plug boot.
Using the above, one could easily build a spark tester whereas they could connect 2, 4, 6, or 8 cylinders all at one time. The ground nail being straight up, the others being bent, aimed at the ground nail. A typical 4 cylinder tester follows:
　
..........X1..........X2
.................X..(grd)
..........X3..........X4

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay store at:

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store

Now, if no spark, disconnect th large RED electrical connector at the engine, crank spark again by jumping the starter solenoid. If you now have spark, replace the ignition switch. If still no spark, suspect the powerpack.
 
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Re: 70hp Johnson dies and won't start back

Makes sence.He just told me earlier that he replaced his old switch cause it was broke and replaced with one out of an old junk boat.I'll let him know what you shared.Thanks for your time.
 
Re: 70hp Johnson dies and won't start back

Hopefully that old switch was the same type and not one that would throw battery voltage to the powerpack.
 
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