1976 Evinrude 70hp lost spark?

[Finlander]

Ran great early in the day, idled fine, started fine!

Went out for the evening bite and about half way to my spot the motor slows down a wee bit. Slow down to start trolling and the motor quits running. Tried to restart but no luck.

Let the motor sit for a while figuring to give it time to let it cool down and see what happens. After about 15 minutes later I managed to get it started and could only go 4mph. So I limped back to my cabin and turned the motor off and it never started again. Check the plugs and they looked good. Checked for spark and there was only one that sparked and that was a weak yellow spark. Checked for gas and that looked good.

Does the power pack in these motors go out suddenly or kinda just like I described? Would the coils all go out the same time?

The motor always ran like a top!

[broken_line]

its possible something got in the points... or your plugs fowled out.. the odds of 2 going at the same time are slim but can happen..

[marine_man]

It kind of sounds like a powerpack to me... It could be coils as well, but I'd bet on powerpacks. I'd swap the power packs around (between two of the cylinders) and see if the no spark issue follows that powepack.

marine_man

[boatfixer]

No points on that engine.

Is the battery fully charged? It needs to be if not.

Yes powerpacks can and do fail suddenly. Weak yellow spark on just 1 cyl? It could also be the stator, but sounds more like the powerpack.

To check the charge coil:

Disconnect the battery. Disconnect the brown wire and brown/orange wire from the power pack and connect an ohm meter btween them, you should get about 630 ohms +/- 75.

Also check from both leads to ground, you should have no continuity.

[Finlander]

Yes I charged the battery. How much does a PowerPack cost?

Used or new?

[marine_man]

Somewhere around $50? Did you verify that that's the issue by swapping them around?

marine_man

[Finlander]

The boat is at the cabin and haven't been able to totally check things out yet. I have the motor's manual on a dvd and will look these parts up and see what it takes to git r done!