I have a Johnson outboard model HD 25 ser# 554695 that belonged to my grandfather. It has not been run in 20 years or more. My father says it has a bad coil as it would run until warm then quit but not seize. The old coil is out but I have it.Where can I find a new coil?Today I pulled out the spark plugs, squirted some penetrating oil in the cylinders and pulled on the starter several times. It got harder and harder to pull intil it wouldn't turn anymore. Did I do something wrong? I've had this motor for several years and when I would occasionaly pull the rope it always felt nice and free with good compression.Are Champion J-6 the correct plug?What kind of lube goes in the gearcase? I drained it and purged out the gunk that was in there with modern gearcase oil and filled it up. I don't intend to run it this way but wanted fresh oil in there just to protect the gears while it is sitting in my garage.Lastly I was wondering if I could narrow down the year of this motor by the serial number.Thanks!