1968 sportwin 9.5 one cylinder

[aridhol]

I have a 68 9.5 sportwin that is running ok but seems to be only one cylinder. I noticed this when I wen to go WOT and it dogged along at about 10mph.
I got new plugs, roughed up the wire in the plug boots and used some dialectric grease with no real change. I can pull the plug wire off the top cylinder while running and it seems to chug along with no change.

I tried swapping the plug wires and it won't even start. When swapped back it starts 1st or second pull.

Lastly it seems to run a LOT better in neutral than in gear (f or rev) .
I have limited tools with me right now (socket set, wrenches , screwdrivers and some sandpaper).

Any diagnostics or fixes I can try would be much appreciated.

 

[lindy46]

So what happens if you pull the bottom plug wire? If it dies, then you know it's firing only on the bottom cylinder. If this is the case, check for spark to the top plug. If no spark, you'll need to pull the flywheel and check the points and coils. If you have spark on the top plug, next check compression.

 

[aridhol]

If I pull the bottom plug it dies.
The spark is there but seems a little weak. It's very hard to see in the blazing sun. I don't have a place to pull the motor and run it so I'm running it in the lake every day.
It's a mystery for my vacation.

 

[twocyclemania]

Have had this happen a few times. It's usually the coil. Also, check your point setting; a few thousandths off and you'll lose spark. Also, make sure the points are cleaned. (fyi; The two cylinder motors will often run on one cylinder but you won't get high end or idle).

 

[boobie]

Pull the flywheel and have a look under there.

 

[aridhol]

I pulled the flywheel and the point I think goes to the cylinder that isn't firing didn't open at all really. I adjusted it with the adjustment screw and it still wouldn't open (maybe a hair). I then pulled it off and the rub side of it was completely worn away so that the cam could not open it up.
I think this is the problem as everything else looks great .

2 questions:

a) What's the recommended way to verify the coils are good? I have a multimeter somewhere....
b) Any place in Canada that I can get new points for a 68 sportwin online? I tried marineengine.com but they want $27 USD for shipping and the part weighs about 2 ounces.... Of course shipping is free to the lower 48.

 

[F_R]

a. If they aren't cracked, they probably are good. If cracked, junk. You can test the windings with your multimeter. Primary winding should be about an ohm, secondary winding a few k-ohms.

b. There are lots of outboard shops in most parts of Canada. That OMC Universal Magneto was made by the millions. Any marine parts guy knows all about it.