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Is there a charging system on a 69 Johnson 25hp...

C

Chad Noben

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I am wondering if there is a charging system that is on or can be used with this motor. Just something that I could hook up to my trolling motor battery. If not, do them solar powered chargers work good?
 
Do not waste time to try to install a 40 HP style generator on the 25 HP.-----------Best to find a newer style 25 / 30 with electric start / battery charging / electronic ignition and a better / stronger gearcase.
 
Your 25 is a fine motor and easy to work on, started out as a 18 HP in 57 and parts are everywhere for it.Stayed in production till about 77.-------Keep water out of the gear oil and it will be fine. Newer 30 cubic inch 25 just had a much stronger gearcase.
 
I found an original Prestolite generator for my 68 33hp Johnson. Had to find an original bracket and belt as well. The hard part was the regulator and I never found an original. I eventually used a Delco replacement regulator for old garden tractor applications, it was rated at around 10 amps. Hooked up the armature wire, field wire and then the pos. wire to the battery. Worked fine just to recharge the cranking battery but wont work to charge trolling motor battery as well. On top of that your not going to get the 10 amps unless your rpms are high so just tooling around the generator really isnt doing but an amp or two.
 
my first new motor was a 69 18hp....same motor as a 25 but i think they just revved up the 25 and rated it at a higher rpm....both weighed 77 pounds i believe....never needed a generator etc.....the only reason to have one is to charge the trolling motor battery and thats a nono anyway to me.....very easy to rope start that little devil...
 
Bottom line... There's no way you can install a generator on that engine and forget about the solar charger. Best bet is to have two good batteries wired together via a good battery 1/2/Off switch, and also have a good battery charger at home to bring them up to par. When boating and trolling, and that first battery goes down.... you know you're half way thru your trolling for the day.
 
That generator HAD to be installed / was standard equipment on the 40 HP electric shift in 1962 , it was no longer an optional item on that motor.
 
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this is an interesting post to me having both a 61' 40hp and 63' elect shift 40hp and previously my father had a 57' 35 johnson ripcord starter, the info and history is coooool.( all on the same 59' boat) taking the gen off my engine for weight and regulator reasons, i will be charging my batt at home. what would be a good batt to use? also charger is getting old any suggestions for a good quality charger?
 
racerone said:
That generator HAD to be installed / was standard equipment on the 40 HP electric shift in 1962 , it was no longer an optional item on that motor.
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Racerone.... I don't know if that was aimed at me or elsewhere. I was speaking of the original 1969 25hp model post.
 
Someone said that the 10 amp generator was " designed for the electric shift "----which is not quite correct , it was available well be fore electric shift came out.
 
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