1962 5.5 Fisherman - no spark on either cylinder

[Sader762]

So there I was enjoying my day on the water when the engine started to give me trouble. I rebuilt this engine about 4 months ago replacing all ignition parts, impeller, head gasket, thermostat, and a carb rebuild kit. This engine had been running great.

While I was underway at WOT the engine lost power for a few seconds then would go back to full power. It did this for several minutes then stopped going back to full power. After several more minutes I could only go about 50% power. After 10 minutes or so it finally just quit on me and would not restart.

First thing I checked was compression and compression is the same - no decrease or loss of pressure in either cylinder.

I then checked spark and I have no spark in wither cylinder. I do have a manual but I don't see anything that would point to both cylinders going out...any ideas?

Thank you for your help, I'd love to get this old girl going again.

 

[F_R]

Re: 1962 5.5 Fisherman - no spark on either cylinder

Well, let's see. You had it apart and it worked for awhile, then quit. The first thing that comes to mind is a sheared flywheel key. If it isn't that, something got loose in there and caused damage. Either case suggests improper assembly, something probably not tightened as it should have been. Doesn't matter, you have to remove the flywheel for a look-see.

Flywheel Key: Flywheel and shaft tapers must be in good conditon, and keyways not battered. Tapers must be clean and dry. Then you MUST use a torque wrench to tighten the nut to 40-45 foot pounds. Maybe you did all that, I have no way of knowing.

 

[Chinewalker]

Re: 1962 5.5 Fisherman - no spark on either cylinder

Could be the point cam wick wasn't oiled, or present? That would make the rocker tip of the points wear fairly quickly and would explain the intermittent nature of the skipping leading up to the failure. I would check the point gap...

 

[Sader762]

Re: 1962 5.5 Fisherman - no spark on either cylinder

Well, let's see. You had it apart and it worked for awhile, then quit. The first thing that comes to mind is a sheared flywheel key. If it isn't that, something got loose in there and caused damage. Either case suggests improper assembly, something probably not tightened as it should have been. Doesn't matter, you have to remove the flywheel for a look-see.

Flywheel Key: Flywheel and shaft tapers must be in good conditon, and keyways not battered. Tapers must be clean and dry. Then you MUST use a torque wrench to tighten the nut to 40-45 foot pounds. Maybe you did all that, I have no way of knowing.

Yep broken flywheel key. Although I don't think it necessarily suggests improper assembly. Could be but I doubt it.

I tightened everything to spec per the Evinrude service manual. This is not my first go around around motors, I think I can handle a little 5.5 horse 2 stroke motor. Something came loose while I was underway or the 50+ year old motor has seen a number of owners over it's lifetime and finally failed.

The question now is what's the fix, I guess I'm off for some reading.

 

[tx1961whaler]

Re: 1962 5.5 Fisherman - no spark on either cylinder

Make sure the taper and bore are smooth and clean and dry, and torque it back down. Also make sure to use a real Evinrude key PN 0120395, not a Home Depot special. If it breaks again, the flywheel is shot because somebody overtightened it.

 

[cajuncook1]

Re: 1962 5.5 Fisherman - no spark on either cylinder

Some people put grease where the flywheel, crank shaft and key meet, so it makes it easier to remove next time. The problem with that, it can cause the flywheel to move around and put pressure on the key and shear it and damage stuff. That connection between the flywheel, crank shaft and key should be dry! The non-lubricated area helps maintain a friction seal to prevent the flywheel from moving around the crankshaft and putting extra pressure on the key and shearing.

Just a thought, but if my description is wrong, someone please correct me.