1975 75hp no spark

[fmalott]

i'm working on a 1975 75 hp johnson no spark at all three coils i tested stator puts out 170 volts while cranking but no power to coils i take it there should be power to the power pack while cranking. when cranking there is no power coming from all three wires at the power pack they are dead.
the issue the motor is having drive for close to 30 minutes then dies will not start again
i thought fuel issue which there was primer ball and line needed new fittings fixed it all up fuel pump excellent went to start it up but no spark
is this year of motor and style of power pack was there an issue with the power pack

 

[ezeke]

Re: 1975 75hp no spark

You can troubleshoot the powerpack as shown here: http://cdielectronics.com/InstallSheet/113-1726.pdf

 

[fmalott]

Re: 1975 75hp no spark

did all the trouble shooting as mentioned in ezeke post. did test with with wires from stator off power pack stayed between 175volts - 225volts that's good according to trouble shooter tested with wires from stator on power pack went to 224 volts trouble shooter says 150volts and above is good, is 224volts to high? none the less there is power from stator going to power pack, tested sensors all good just no power to coils, i even disconected rectifier no difference so i ordered new power pack we will see what happens, other than that can anyone think of something else to test