'68 Evinrude sportwin 9.5 running on one cylinder

Aridhol

Active Member
Hey all, I'm up at the lake with limited service and tools and just discovered my kicker is only running on one cylinder (I can pull the top plug wire while running and it keeps chugging along. When giving it full throttle it sometimes revs up which I think is the top cylinder firing.
We've cleaned the contacts on the plug boots and put in new j6c plugs, same issue.

Any simple things I can try to diagnose the issue for sure or fix that can be done with limited tools?
 
if you pull the suspect cylinder plug and put it in the plug boot, and hold or place the plug against the cylinder head or something metallic can you see a good spark for every revolution? can you see the cylinder going up and down from looking inside the plug hole?
 
if you pull the suspect cylinder plug and put it in the plug boot, and hold or place the plug against the cylinder head or something metallic can you see a good spark for every revolution? can you see the cylinder going up and down from looking inside the plug hole?

It appears to spark each Rev and we do see the cylinder move in the hole. After playing with it or seems to only do it in gear. In neutral we can max it out and it seems to run smooth. That being said I can only turn the throttle so much in neutral.

I think I mentioned it but occasionally it seems to spark and Rev up for a few seconds, could it be not enough air getting in or not enough fuel?
 
Switch the coils, see if the misfire stays on the same cylinder.
 
Agree with switching coils to see if the problem follows the switch...those engines also have points under the flywheel...they are likely corroded or worn out and I'm betting that will be the problem. I' ve had many of those engines in years past
 
I can't even get it started with the plug wires switched.
Tested again on the water and I can pull the plug wire off the top cylinder and it keeps running as it was
It sounds way way better in neutral but in forward or reverse it seems to be rougher and vibrates more
When I play with the "low speed" rich/lean screw on the front I see some improvement if I lean it out
 
Switching just the wires will put it totally out of sync and it won't run...if it has coil packs all you are doing is putting the complete bottom coil assembly so it now fires the top cylinder and the top to the bottom....you can't just pull the wires off the plugs and switch...I'm positive that engine won't have individual coils I think that came in the 80's so it makes me sure that you are going to find it is a points problem....with an engine that old...if they have never been done which is possible they will need replacing...they are cheap too... you may need a puller to get the flywheel off to get at them.
 
Switching just the wires will put it totally out of sync and it won't run...if it has coil packs all you are doing is putting the complete bottom coil assembly so it now fires the top cylinder and the top to the bottom....you can't just pull the wires off the plugs and switch...I'm positive that engine won't have individual coils I think that came in the 80's so it makes me sure that you are going to find it is a points problem....with an engine that old...if they have never been done which is possible they will need replacing...they are cheap too... you may need a puller to get the flywheel off to get at them.

I figured I was doing something stupid. I don't have the equipment here to pull the flywheel and never even seen the underside of one so id be out of my depth until a read a bunch more.

Thanks all for the advice.
 
Points are a snap to replace...they are typically on a bracket that is held down in place with a couple of screws...you just need to set them at the specified gap...so you need a set of feeler gauges...same as setting spark plug gap. Taking flywheel off is easy...just need to remove the nut..an impact gun works best because you won't have to worry about preventing the flywheel from spinning as you loosen it....if you use a normal socket the flywheel will need to be secured to prevent it from turning as you loosen the nut. The crankshaft is tapered where the flywheel sits so you need a cheap Can Tire puller to pop it free. Once off it is a job anyone can tackle.
 
Here you go...there are coils under the flywheel and two sets of points...the flywheel in this video has been removed but this shows what you will find under it...the guy has the same symptoms as you describe
https://www.youtube.com/watch?v=H_B_c9mlkj8
 
Pulling a flywheel on OMC 9.9

I figured I was doing something stupid. I don't have the equipment here to pull the flywheel and never even seen the underside of one so id be out of my depth until a read a bunch more.

Thanks all for the advice.
Hey, its not that bad to pull it, loosen the locknut a few turns, leaving it completely on threads, take a piece of wood and tap the nut with the wood between while pulling up on the flywheel. You are going to be trying to lift the wheel while tapping on the shaft. At home I use block of hardwood, take care not to damage threads.
Good Luck.
 
Aridhol: if you don't have one already, go online ASAP and buy the factory manual for your engine and correct year. IMHO third-party books from places like Seloc don't cut it, they cover several model years and engine sizes, information can be too generic to be much use. Try www.outboardbooks.com, looks like they have your engine's service manual:
https://www.outboardbooks.com/manual/9822/
 
I've pulled the flywheel and inspected the points and one seems good (the good cylinder) but the other won't open very far. I used the adjustment screw and I could barely get a 8 thousandths feeler gauge in there.
I pulled it off and it looks like the rubbing surface that gets pushed by the cam to open up is totally worn away.

the coils look pretty good no cracking or anything.
I need a replacement points breaker and I found one on marineengine.com but it's $27 shipping for a $8 part...
Would this be something I could source on the island somewhere or even in Canada? I'm not even sure who I should be calling.
 
How about Parker Marine, they service OMC and claim to have used outboards for parts, I think they could get points in for you.
 
Check the coil out while you have it apart. Just because it doesn't have a crack doesn't guarantee it isn't faulty as well.
 
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