71 60 hp johnson sometimes fires

[ruaporpoise]

not showing pulse from amplifier blue wire to coil when points lead is lifted from ground. however she has a history of sometimes spark sometimes not.can amplifier sometimes work and sometimes not.set my multimeter to 250 ma setting and needle is slamming off scale when touched to purple amp lead also peggs out on grey tach lead

 

[Joe Reeves]

Re: 71 60 hp johnson sometimes fires

That ignition system is what's called a Battery Capacitance Discharge ignition system. Unfortunately it is possible to have an intermitent problem with that type powerpack. From what you've said about the blue wire, in this instance, that may be the case.

 

[ruaporpoise]

Re: 71 60 hp johnson sometimes fires

so bottom line is no pulse from blue=bad pack. or are there other components to consider ie; temp sensor on same terminal as purple power in.and would it be a bad idea or not to go cheap with retrofit as suggested in other posts I've read, conventional coil,condensor and resistor

 

[The Marine Doctor]

Re: 71 60 hp johnson sometimes fires

There must be a 12volt supply to the Powerpack for it to fire. Make sure the supply is constant..then if spark is still an issue...replace the pack.<br /><br />TMD

 

[Water Hole]

Re: 71 60 hp johnson sometimes fires

I am having this same problem with my motor. I bought this motor from a guy that bought it from a guy, etc... I have been in the process of fixing it up, and it has been running halfway decent which has allowed me to work on the carbs. I never could get it to run exactly right. I just checked the ignition by looking at the plugs (which are new, gapped to .030) I get a real weak spark at all of the plugs. made sure the points are set correctly .010 at all three lobes. I tried the amplifier test in the manual and couldn't get any voltage reading on the output of the amplifier, yet I was still seeing some spark at the plug. I can also hear the amplifier ticking when the ignition is on. I have removed the clipper from the system per advice that I have read here and repaired the bad wiring in the harness (intend on replacing harness completely). I have looked at the distributor components and am suspicious of the "rotor button" as it looks old and the connection points are somewhat corroded. could these parts be bad, causing me to lose voltage before it gets to the plugs? does my amplifier sound like it is bad? I tried using an automotive test light at the blue output wire from the amplifier and get nothing, but when it is connected to the coil (which is new) I get the weak spark at the plugs. what do you think? thanks for all the great info. Waterhole

 

[phipps]

Re: 71 60 hp johnson sometimes fires

....I have removed the clipper from the system per advice that I have read here....

I, too, am working on a 71 60hp. Do you have any links to the threads discussing removal of the clipper circuit? I have a Sierra aftermarket amplifier and Ive seen mention of removing the clipper, but cant seem to find whether mine should have been removed when the Sierra was installed.

I have no spark at all so youre one step ahead of me. I have found that I have no continuity through my points so Im hoping that is my problem.