One cylinder not running - no spark

[kayakman12345]

I have a 1969 evinrude 6 hp outboard and when I was out fishing today one cylinder was not firing on the way back (the bottom cylinder).

I am trying to figure out what the problem is? I put in a new spark plug and no spark. Top cylinder has spark bottom one does not. Motor runs on one cylinder.

I tested the coil using a ohm meter and it reads 3.8 and top coil read 3.9 so I don't suspect its the coil. I tested it by putting the positive end of the multi in the spark plug case and the negative to the block.

I dont have a puller yet to pull the flywheel off to look at points and condenser but a suggestion as to what it most likely would be would be helpful to narrow my search.

This motor purrs like a kitten when running.

Thanks

 

[bktheking]

Re: One cylinder not running - no spark

Points and or condensor, just order both and replace. Once you get the flywheel off you'll know more, could just need to be cleaned or adjusted or a wire could be broken.

 

[jdsgrog]

Re: One cylinder not running - no spark

welcome to iboats.

obviously something is wrong with the ignition. i am assuming you are testing the spark with a spark plug tester? you will need to pull the flywheel. be sure the points are clean and gapped at .020. it's got to be something in the ignition-coils, points, condensers, spark plug wires. if there is no spark, it is likely grounding somewhere or may be arcing. i believe the "top secret" thread gives you the checks.

 

[emckelvy]

Re: One cylinder not running - no spark

Most likely it's the points. If they have not been serviced for a long time, either dirty, oily, or gap has closed up.

If they're not in too bad of shape you can clean & degrease them & adjust gap to .020". Of course a new Tune-Up kit (points, condensers, felt lubricator & grease) is less than $20 here at iBoats, and many places and well worth installing.

Be sure to check the suspect coil for cracks in the insulation, or arc marks which would indicate a problem. Coils are relatively inexpensive also if you end up having a bad one. Take a good look at the spark plug wire just in case it's rubbed-thru somewhere.

You can use an automotive harmonic balancer puller to remove the flywheel. By all means, never pull on the outer edges of the flywheel as it can be permanently damaged.

Use Grade 8 or better 1/4-20 bolts of suitable length, be sure they're threaded into the puller holes in the flywheel with plenty of thread engagement, to preclude pulling the threads out of the holes.

Clean any rust off both the crankshaft and flywheel tapers and reinstall dry. Torque the flywheel to specs to avoid stripping-out the key or keyway.

HTH & G'luck.........ed

 

[kayakman12345]

Re: One cylinder not running - no spark

Thanks for the quick responses.

I will look for a puller and take of the flywheel and see if I can get away with out ordering new points and condensers or if upon inspection looks bad I will order a new set and install but then I cant fish until it comes in....lol

I dont have a manual for the motor so I am working on limit knowledge and the seat of my pants...lol....but reading on this site I should re-torque the flywheel at 40-50 ft-lbs.

 

[mikesea]

Re: One cylinder not running - no spark

Be sure to inspect the coils carefully.They do go bad with time.You might want to just change everything ,coils,points,condensers while under there.Im enclosing a pic.of coils that have just simply gone bad with time.for some reason my copy/paste isnt working,but go to the receint posting' "ancient 3 hp johnson"or something like that ,he has a picture of cracked coils on the reply