Need Pro Advice - Ignition Coil

[Can't Cast]

Hey all,

I recently bought a 1978 Japanese Mariner model 15C (15 hp 2 cyl). I got it dirt cheap ($40). Previous owner said it ran several years ago, but won't start now.
I cleaned the carb (properly), and checked fuel pump diaphragms (both OK), but she still won't crank up. Compression is 100 & 101 PSI, and she gets fuel. I checked spark and lower cylinder is very weak orange. Did resistance test on ignition coil, and found secondary winding is 13k (should be 5-6k ohms). Top ignition coil is OK, and nice blue spark.
Now for my questions:

I cannot find a replacement coil, this is an old style points/ condenser magneto system with no CDI switches or any electronic ignition stuff. These ignition coils are no longer available, and I can't find a part # other than the marking on the coil, which are CM61-25 followed by AL810.
There are coils which are made for CDI ignition systems that are identical in appearance, but have different resistance values in both the primary and secondary windings (both are lower). These coils are available, but will they work properly in an old point type magneto system?
Also, one other question. Most outboards have different part #'s for upper and lower cylinder ignition coils. The coils look the same, and resistance is the same. Is there really any true difference in the coils, or is this just a marketing scheme?
Thanks in advance for any answers. Hopefully someone knowledgeable in this area can steer me in the right direction. I'm 99% sure I can get this puppy to run if I can find a coil that will work. I'm pretty handy with smaller outboards, but I'll admit I'm not a pro and sometimes need some "HELP"...

 

[CharlieB]

Re: Need Pro Advice - Ignition Coil

Are you sure that is a 15C?

The Merc parts site shows the 15C to be an electronic ignition.

I didn't find a points ignition til I looked up the International model, and yes, most all ignition parts are NLA.

I've often found NLA parts available at Sea-way Marine in Seattle.

I've also found a phone call to Techs at CDI to be helpful in finding a substitute coil for another model I had in my shop.

 

[Can't Cast]

Re: Need Pro Advice - Ignition Coil

CharlieB,

Yes, it's a 15C...1st year model. Thanks for your reply and I'll try to call those places you listed.
Unfortunately, this is probably the only year they didn't have electronic ignition on the 15C. That's my luck for ya!
I've scoured the net, but cannot even find a parts listing for this year...much less a coil.
Take care my friend, and thanks again.

EDIT: - Had some free time today, so I decided to try and pull the flywheel to check points, condensers, and trigger coil. All those parts are in great shape...however the woodruff key that locks the flywheel to the crankshaft was SHEARED and the flywheel was turned about 90 degrees from where it's supposed to sit. Bet this is also a BIG factor in why this thing wouldn't crank!!!
A woodruff key and a coil...and I know this thing will run!!! I'd bet money on that...er...if I had any.