6v to 12v?

[evinrude enthusiast 93]

I have 3 antique evinrudes that all have electric start from my understanding they all used to run on 6v batteries.
​the engines I have are a 1956 evinrude big twin a 1956 evinrude fast twin golden jubilee and a 1959 lark black model
is there anything special u have to do to convert them?
I will be rewiring them soon and want to know ahead of time what is different between the 6v and 12v systems any info would be appreciated.

 

[jbcurt00]

Moved to the outboard motor forum

 

[F_R]

The 1959 should already be a 12V system. You can re-wire the others and continue to use the 6V starter on 12V. If you don't want to change the choke solenoid, insert a voltage dropping resistor in series with it.

 

[F_R]

No Title

 

[evinrude enthusiast 93]

thanks for the diagram fr I do have a small library for each of my motors wire systems and I see the selenoids have to be upgraded and obviously the wire gage should be upgraded as well but are there any other requirements for the conversion?

 

[gm280]

Not being familiar with any of those engines, does any of them have a stator and rectifier/regular? If so then they would be outputting a voltage to charge the battery and it will not be high enough for a 12 volt battery charge. But I honestly don't know how they are built. :noidea:

 

[evinrude enthusiast 93]

No Title

as far as I know off hand the two larger motors consist of starter, starter solenoid, choke solenoid, speed limiting mercury switch, and ignition switch/start control. I have attatched a basic diagram I use. as for the golden jubilee I am unsure I can also attatch a diagram for this engine

 

[racerone]

There were no 6 volt charging systems available in the 1950's ------There was a belt driven 12 volt generator available as an option in the late 1950's----Ignition / spark systems do not use 12 volts to make the spark on these motors.

 

[evinrude enthusiast 93]

so I guess I would just run a 6 volt battery and rewire the pre existing components. the battery would have to be recharged every time just like the trolling motor I would assume bc I'm sure the chances of finding on of these generators is slim to none now a days altho I may be able to modify something similar that would take some research but shouldn't be too hard to figure out.

 

[racerone]

The battery is only used for cranking the motor over to start.--------A good / fully charged battery will start a properly tuned engine an amazing number of times.-------No need to charge the battery every week unless you are running a lot of other 12 volt items on the boat.

 

[evinrude enthusiast 93]

just my electric start and lights at night. got rid of mr troll past fall. so running just the bare necessity's. so could I start It with a 12v that I use to run my lights with? or do u need separate batterys?

 

[racerone]

Just one good sized battery is all you would need.--Motor in good state of tune will start in just seconds.----If not then you need the address issues with the motor.-----2 running lights on a boat do not draw amperage like headlights on a vehicle.

 

[evinrude enthusiast 93]

ok thanks for the advice. I was running a 24 volt Nichols aqua last year but sold it with the trolling motor so ill be getting new 12v when I get them running on pull starts. ik the big twin electro start works just needs a carb rebuild still have to test the others electrical systems. ill be updating when I figure out more and dig into the electrcan wires to replace them

 

[F_R]

thanks for the diagram fr I do have a small library for each of my motors wire systems and I see the selenoids have to be upgraded and obviously the wire gage should be upgraded as well but are there any other requirements for the conversion?

The wire gauge does not have to be changed. In fact, 6V systems use heavier wire than 12V systems. That means 6V wires are actually larger than necessary (not a problem).

 

[evinrude enthusiast 93]

I see that my engine has 3 guage I seen 4 guage at the marina for 12v which is smaller in any case I will just be replacing the existing wire with the same guage it currently has except terminal guage ill be switching to 4 ga bc I have a roll in the garage I use for car amp units that will work as well. I see the existing wire is not nickel coated but have seen many "marine" grade is nickel coated copper is this for corrosion prevention aside from the rubber coating or some other reason?

 

[F_R]

The plating helps protect against corrosion.

 

[evinrude enthusiast 93]

I figured so

 

[HighTrim]

If you do convert to 12 volts, just ensure you change the choke solenoid out for a 12 volt one from a later, '57, '58, '59 etc.... 35hp omc. you will fry the 6 volt one on a 12 volt battery. The starter will be fine though.

 

[evinrude enthusiast 93]

can anyone tell me how mutch these motors would be worth in fair running condition? the lark is in good condition others are fair

 

[racerone]

People who know these motors pick them up " as is " for next to nothing.---If you have a good one there are few buyers as most shops will not work on them.----Folks who can not do their own work do not want them because shop labour is the killer.