1978 Evinrude Suddenly Won't Start

Alternator/Generator/voltage regulator bad?

This is where I'd start, sounds like its not charging the battery back up to me.

We had a mercury engine that the battery would always die on, and if you let it sit the battery would slowly drain. The marina's solution was to put a battery cut off switch so we could shut off the battery.

When I got older and wiser I opened the engine cover and quickly found and replaced the rectifier module, which had a blown out diode as noted by the burnt hole on it.

Try mechanical engineering.

It's funny, I don't even know if an outboard motor has an on board charging system...

My old 18hp seahorse outboard just has a pull start.. no battery.

So.... do the new electronic start outboards have a charging system?? (I'm guessing yes... but really don't know) Or do they just drain the battery to run the plugs?

Hmmm... no advice like advise coming from a guy who knows nothing about the subject....

^{should i even post this?}

Yes they do. The charging system is built right in. I have a Johnson outboard but have had the cover off so little that I couldn't point to the thing, but it's there.

Your motor probably has a magneto.

Take care.

My experience is with cars, but it should also apply here.

Check both ends of the cable from battery to starter. If there is a loose connection or corrosion from a leak in the old battery, it may cause the problem you have. A poor connection at the battery may also cause regulation problems for the alternator, and electrical noise that may throw your tachometer off. The battery may actually still be fully charged, but a bad connection will have too much resistance for the starter to run. If the cable is corroded where the wire goes inside the connector, a jumper cable on the connector won't work either.

I learned the hard way to avoid putting too much bending load on battery posts when wrenching on the clamps. Even a little can make microscopic cracks in the seal between the battery case and post that will eventually leak enough acid or sulfur dioxide fumes to corrode the terminal or cable. Now I hold the clamp with one hand and apply a counter-torque to keep the twisting action of the wrench from bending the battery post. Since I made that my practice, I rarely have corrosion problems.

Greetings.

Make sure that all connections are cleaned down to bare metal and put a little marine grease on each connection to keep out air and corrosion. The poor connections will carry the voltage but not the current required to function correctly.

I had a 39 Plymouth coupe that would run the battery down when you drove it. Limited knowledge, high frustration, no long dates. My uncle, a master mechanic, came out to the island to visit and said the battery was hooked up backwards. I put a steel bar across the terminals until it was discharged (bar got red hot) and then charged it up correctly and hooked up the battery correctly. The body perfect car ran great and that was why the car was only $20.00 in 1961. A great deal for a poor 16 year old.

I had a 67 429 Cadillac that had a starter that barely turned over causing quite a drain on the battery. The one bushing was worn and was a in vehicle fairly quick and inexpensive fix.

Wish this kind of forum was available abck in 1961. All of my friends were as befudled as I was. If I could only remember all of the wierd ideas they thought would solve my problem.

Thoughts of 49 years of sparing with motors.

May you glean the answer from all of the CR4 inputs. And let us know what the answer is. Good troubleshooting.

I always have at least 3 batterys wired togeather = 12 volts with a lot of amps and a solar panel to keep them charged. With the engine reving to 7000 I have to ask do you have oil in the gas mix ? If you do not have enough oil the engine over heats and the pistons will not move. Too hot and you lose the block.