I've got a 1977 85HP Johnson (85EL77S) and I'm not getting spark on cylinder #3. I checked it with a spark tester and all other cylinders are sparking. I found this, but I'm no mechanic and don't quite understand what to do. Can anyone explain what they are saying:

No fire or Intermittent on One Cylinder:
Check the DVA output on the orange wires from the power pack while connected to the ignition coils. You should have a reading of at least 150V or more. If the reading is low on one cylinder, disconnect the orange wire from the ignition coil for that cylinder and reconnect it to a load resistor. Retest. If the reading is now good, the ignition coil is likely bad. A continued low reading indicates a bad power pack.

I used a volt meter to try and check the voltage of the orange wires on each cylinder, but the numbers were fluctuating so fast I couldn't read them. Also, I'm not sure what a load resistor is or what it means when it says to remove one wire and reconnect it to a load resistor. Any help is greatly appreciated. Don't really have the money to take it to the shop right now, but I've got the time to figure this out.

Do like he said, but instead of the load resister,swope the the wire for the coil output next to the one that dose not work, if that coil now has fire its the pack, if the same coil is still not sparking then its the coil. Most likely the pack is bad. They are the problem 95% of the time,,but coils and timer bases go bad also. Cary carysmobilemarine.com

Replaced the powerpack and took it out on the lake and everything ran great. Thanks for your help!

Now if I can just figure out why my carbs are leaking. A mechanic I talked to today told me to fill them up with sea foam and let it sit over night. Maybe that will be my next project.

your carbs are leaking because the float valves aren't seating properly. most likely worn out float valves/seats.

carb rebuild with new kits will fix it.

BTW, a "DVA" is a "direct voltage adapter", you use it with your voltmeter to read "peak AC voltage" -- basically shows you the peak voltage instead of all the fluctuations.

BTW, I have a 1980 model of that same engine..so do yourself a favor...carry a spare coil and spare starter solenoid in the boat at all times. Spare plugs too.

Dont ask me how I know..