1969 Evinrude 85hp ignition conversion

[65wgn440]

I am looking for any info on converting these old OMC ignition systems over to a MSD 6A set-up. I believe they were used from like '68 up to '73-4 maybe. I have read about it being a do-able swap, but just wondered if anyone on here would have any good info. Basically I believe I need to cut the output voltage of the MSD in half, in order to not burn out the cap and rotor. One guy said he ran two coils and grounded the coil wire of one of them to achieve it. I thought I could maybe just cut down the input voltage to coil, by adding a resistor, and then I would only have to run one coil ( for packaging purposes mostly). Any thoughts would be appreciated, thanks. BTW, I talked to MSD twice and they were zero help.

 

[Don Frelier]

I had a 1969 55 3 cylinder evinrude and it still had points to trigger the ECU, likely the 85 is the same setup.
To replace the OMC ECU I used a "points saver" for small engines and a volkswagen coil.

Now they sell an upgraded version called the transdenser II

If you get a small enough coil with the correct input resistance you might be able to fit it under the cowling.
http://overnight-solutions.com/Index_Files/Transdenser II Information.html

 

[65wgn440]

Very interesting. Thank you very much for the info. Could it really be that simple and cheap to fix this problem ? So did you have the 55hp for long after you installed that set-up ? Ran fine at all RPM's ?

I had a 1969 55 3 cylinder evinrude and it still had points to trigger the ECU, likely the 85 is the same setup.
To replace the OMC ECU I used a "points saver" for small engines and a volkswagen coil.

Now they sell an upgraded version called the transdenser II

If you get a small enough coil with the correct input resistance you might be able to fit it under the cowling.
http://overnight-solutions.com/Index_Files/Transdenser II Information.html

I had a 1969 55 3 cylinder evinrude and it still had points to trigger the ECU, likely the 85 is the same setup.
To replace the OMC ECU I used a "points saver" for small engines and a volkswagen coil.

Now they sell an upgraded version called the transdenser II

If you get a small enough coil with the correct input resistance you might be able to fit it under the cowling.
http://overnight-solutions.com/Index_Files/Transdenser II Information.html

 

[Don Frelier]

I had it for a couple of years. It has terrific low end torque and would spin up with no ignition limitations.

 

[65wgn440]

I had it for a couple of years. It has terrific low end torque and would spin up with no ignition limitations.

Hey Don, just wanted to thank you again for providing me with that information for ignition set-up. Ordered the Transdenser II unit from Dale at Overnight Solutions and it is installed and working perfectly ! You saved me money and frustration. Doug