1976 Johnson 85hp No Spark

[billgrob]

I can't get spark on any cylinder. I've pulled the black yellow kill wire, disconnected the rectifier, replaced the power pack and now the stator and still can't get any spark. My question is should I have power to both yellow wires going to the stator? Also should the power pack have 12volts at any point before the engine is running? I don't have either.

 

[boobie]

Re: 1976 Johnson 85hp No Spark

Go to CDI Electronics.com. They have a good troubleshooting guide. And no, no 12 volts to the power pack.

 

[emdsapmgr]

Re: 1976 Johnson 85hp No Spark

You can do a preliminary spark test. You could disconnect the wiring harness to the control box. Jump start the starter from a charged battery with automotive jumper cables and check for spark. (be careful, as if you start the engine, you won't be able to shut if off.) If you have spark, then the problem is in the control box wire harness or key switch. If still no spark, then you need to follow the troubleshooting that boobie recommends.

 

[billgrob]

Re: 1976 Johnson 85hp No Spark

I took the boat to a mechanic and he determined the power pack was bad. So I mailed it to CDI to confirm and it was bad but not under warranty. I am getting voltage at the black/yellow kill wire which is what is frying my power packs. Any ideas where the voltage could be leaking from?

 

[boobie]

Re: 1976 Johnson 85hp No Spark

Possibly the igniton switch or in the wireing harness.

 

[billgrob]

Re: 1976 Johnson 85hp No Spark

Still not able to get this motor running. I have bought another new power pack because I blew out the diode on the old new one. I also bought new battery cables and a new wire harness (boat side), new ignition switch, new coils, new stator, new spark plugs, and rebuilt the carbs. I have to have some wires crossed or something. This is crazy that my motor won't run. Any fresh ideas are welcome. I have ran threw all the CDI tests that don't involve testing DVA. Thanks.

 

[boobie]

Re: 1976 Johnson 85hp No Spark

If you don't have a DVA it's pretty hard to troubleshoot an ignition system.

 

[emdsapmgr]

Re: 1976 Johnson 85hp No Spark

Some additional information would be helpful: Does the engine crank? If so, does the engine appear to fire? Do you get any backfiring during cranking? When you crank the engine, are the plugs wet or dry? If you put an inductive timing light on each plugwire during cranking, do you have fire?

 

[billgrob]

Re: 1976 Johnson 85hp No Spark

The engine cranks very fast and plugs are wet. No spark on any cylinder. With a test light I only get power to the red wire on the bus bar. The power doesn't go beyond that. Could a bad rectifier be my problem. Should there be power to the pack?

 

[emdsapmgr]

Re: 1976 Johnson 85hp No Spark

The rectifier uses coils on the stator to recharge the battery and run the tach. There are separate charge coils which will make voltage to operate the ignition system. Once the starter cranks the flywheel at 200 rpm's or more, the charge coils will make power to run the ignition. If you have a weak battery, you may not be cranking fast enough to make sufficient voltage to fire the plugs.

 

[billgrob]

Re: 1976 Johnson 85hp No Spark

Alright my engine is finally running again. I was wrong in my last post; I was getting spark and plugs were dry. Once I check my plugs again I realized the mistake. I started it a couple times with starter fluid and then she came to life and runs normal. Finally... I'm not positive what was causing my power pack blow outs but since everything is new I hope the problem is now squashed. Thanks everyone for their input.