That about does it.....I usually get a long skinny brush and degrease/clean out the tilt tube.
When it's out of the tilt tube try it then....if still hard you will have to purchase a new cable.
Good luck.
I'd say you had a bad switch either internally or on the dash.
The pump should only receive power from one source at a time.
Does the pump have an auto water sensing switch on it or a manual moving switch?
Funny, I have a 77 and the foot is configured like this. I wonder why they used 2 and maybe even 3 during those years. Was a 28 a downsized outboard? Maybe they had lots of gearcase's laying around?
I also wonder if there all interchangeable.
Sometimes kill switches will test correctly with continuity but not work right. Many more volts going through them.
I would unhook them and see if the top cylinder fires.