ARRGH! 71 Johnson 50hp stumped and more stumped

Orkazim

Cadet
Joined
Apr 20, 2003
Messages
12
Hey all,<br />Have a 71 Johnson 50 hp electric shift, etc, etc. <br />Got the "no spark" syndrome! Replaced the power pack II (because it was bad according to the bench test)and also the coils, oh and the rectifier. Everything else ohms out and tests out correctly as defined in the Johson service manual. However I do not have that fancy neon tester. So is there any way to test the stator and timer base without it? <br /><br />I absolutely cannot find anything else wrong. I get power to the pack and it stays there under cranking, from what I can tell my keyswitch is fine, and...and I don't know where to go next. <br /><br />I have two timer bases, both used, the original and one of an old 72 50 horse that blew the powerhead. Tried the extra and still no spark. My stator is in good condition, not oozing and no cracks. And like I mentioned before they are not grounded and spec out correctly! <br /><br />Could my clearance between sensor and flywheel be off? If so, is that something I can adjust and how do I know when its right??<br />Also, recommend a set of plugs for this motor...!<br /><br />Please help this yankee get his boat running the waters of Georgia!<br /><br />Thanks,<br />No-T<br /> cjs@ezworks.net<br />to the top
 

Orkazim

Cadet
Joined
Apr 20, 2003
Messages
12
Re: ARRGH! 71 Johnson 50hp stumped and more stumped

bump bumpity bump<br />come on i know this is common question but i can't find any good answers in the searches
 

ajp

Petty Officer 1st Class
Joined
Jan 6, 2002
Messages
280
Re: ARRGH! 71 Johnson 50hp stumped and more stumped

Does your motor have an airgap sensor. If so it must be a .028 gap. Any different and you will get intermittant spark. If the sensor is bad, you will get no spark. If the 2 wires are bad or cut you will not get spark.<br /><br />Question?<br /><br />Is your coil firing? If so the pack is fine and the Distributor or rotor is bad.<br /><br />On my 1969 115HP I had the following problems:<br /><br />1st - One of the wires to the sensor was loose causing a loss of signal to the pack. <br /><br />Cracked sensor - Wouldn't maintain correct gap. caused a loss of fire and weak or no spark.
 

The Marine Doctor

Commander
Joined
Jul 25, 2003
Messages
2,177
Re: ARRGH! 71 Johnson 50hp stumped and more stumped

Remove the yellow/black from the powerpack...then spin it over for spark. You will not be able to turn the engine off though once its removed.<br /><br />So choke it out if you must if it starts.<br /><br />Yellow/Black is the kill wire from the Ign switch.<br />TMD
 
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