1975 Johnson 70 H.P. has power to power pack but no power to the coils.

[ltforever]

I am new to this whole diagnosis thing. My boat recently started running on one cylinder, so I replaced the plugs. Now no spark at all on any cylinder. I disconnected cable going to key switch and jumped starter still no spark, reconnected cable and took test light to wires coming from stator to power pack, I have power at all three leads going into power pack. I then touched wires where coils connect to power pack and no power. Does this mean need new power pack? Please help

 

[turtles11756]

Re: 1975 Johnson 70 H.P. has power to power pack but no power to the coils.

check all the ground wires at the coils. i have the same motor and it lost spark from that alone

 

[F_R]

Re: 1975 Johnson 70 H.P. has power to power pack but no power to the coils.

I am new to this whole diagnosis thing. My boat recently started running on one cylinder, so I replaced the plugs. Now no spark at all on any cylinder. I disconnected cable going to key switch and jumped starter still no spark, reconnected cable and took test light to wires coming from stator to power pack, I have power at all three leads going into power pack. I then touched wires where coils connect to power pack and no power. Does this mean need new power pack? Please help

No, it means that your test methods are inadequate. To do it right requires a peak reading voltmeter, usually called a DVA. But before you go that far, disconnect the black with yellow stripe wire from the power pack and see if you then have spark. The wire is the kill wire to shut the motor off.

 

[ltforever]

Re: 1975 Johnson 70 H.P. has power to power pack but no power to the coils.

Ok I disconnected the kill switch wire from power pack and tried it still no spark, as I was hooking wire back up to power pack I got a shock because forgot to shut of switch. So don't know what else to do except by power pack. The ground wires look all good and look like good connections

 

[thunderbird123]

Re: 1975 Johnson 70 H.P. has power to power pack but no power to the coils.

Ok I disconnected the kill switch wire from power pack and tried it still no spark, as I was hooking wire back up to power pack I got a shock because forgot to shut of switch. So don't know what else to do except by power pack. The ground wires look all good and look like good connections

I have the same problem can't wait for the next step of direction

 

[ltforever]

Re: 1975 Johnson 70 H.P. has power to power pack but no power to the coils.

Well cleaned all the grounds, took 150 grit sandpaper to both sides of coils cleaned black paint off them, cleaned mounting surface with sandpaper, sandpapered all ground wires and terminal black connections with sandpaper. Terminal block is thin black that goes horizontal with wires coming off it. Put it all back together and turned it over, didn't even get a half a turn over of the motor and it fired right up. Thanks for the help turtle 11756 so far so good.

 

[thunderbird123]

Re: 1975 Johnson 70 H.P. has power to power pack but no power to the coils.

i tested my engine and found that power was going to the power pack slightly ( to the fifth and only the 6th when the engine is on) and no power to the coils. I'm very lost and would appreciate any further instructions.