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1997 Mercury 20 hp 2 stroke charging system

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bosco659

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Although my newly acquired 20 hp Merc does not have an electric starter, I’d like to have the engine charge the battery that powers lights, pumps etc. Do I just need the stator coil and rectifier or do I need a lot more? Will the existing flywheel need to be replaced? Maybe simpler to sell this motor and buy an electric start engine? Thanks.
 
The charging system on those is only about 5 amps and that is at about 4000 rpm. So unless you want to run around the lake at WOT for a couple hrs to charge the battery. Those charging systems are really not worth it ,I pulled it out of my 25. That way I am not always tied to a battery. If you really want it you will need the charging coils and a rectifier. Then run the positive off of the rectifier to the battery then run a negative from a ground on the motor to the battery. You are better off with a good deep cycle battery and charge it at home. If you want to add electric start to your motor find a parts motor They are easy to install.
 
To add electric start you will need the ring gear for the flywheel,a solenoid, a starter and the tiller switch assembly which is around a $100. The kit # is 87-95810a8 and comes with the neutral safety switch. The ring gear and other bits can be found used.[h=1][/h] [h=1][/h]
 
There’s a local guy selling all of the required bits from a 2003, 25 hp. Would you know if they would fit my ‘97? If I get the model and serial number from him, I can cross reference part numbers, but thought someone my know this off the top of their head.
 
bosco659 said:
There’s a local guy selling all of the required bits from a 2003, 25 hp. Would you know if they would fit my ‘97? If I get the model and serial number from him, I can cross reference part numbers, but thought someone my know this off the top of their head.
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As long as it is a Mercury built motor it will fit.
 
Battery is only for lights, bilge pump and live well, no trolling motor. Just thought normal running of the engine could keep the battery topped up.
 
I found a local guy that sold me everything (90%) that I need to convert my engine to an electric start. Can anyone tell me what gauge wire I need for the starter? The battery is close by do the cables will only be about 5 ft max. Thanks
 
I started to install the pieces I bought to covert my motor to electric start. I was supplied with a flywheel but I noticed that the new (used) flywheel has 4 magnets and the one I took off only has two. I’m thinking to just remove the ring gear from the new one and put it on my old flywheel. I figured the extra magnets were not intended to be used with the existing switch ox and related components.
 
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