85hp - Change Rectifier for Regulator?

Mark42

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I was wondering if it is common to replace the retifier with a voltage regulator. I am also wondering how many amps the 1985 85hp magnito is putting out, and if I add a regulator it would be better for running any electronic accessories like VHF radio. Rectifiers can put out high voltage at high RPM, and I don't want to be damaging any accessories.
 

Frank Acampora

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Re: 85hp - Change Rectifier for Regulator?

I have often wondered about that myself and someday will experiment putting on my Force an old Motorola regulator/rectifier From a Chrysler. Problem is I know the frequency of the Chrysler 12 pole alternator, but I don't know how many poles of the 20 pole Force stator are used for the alternator. Therefore I do not know the frequency of the 20 pole a/c current and I do not know if a higher frequency will damage the Motorola unit. However, Chrysler, before they went to Motorola, also used a selenium rectifier with a trip regulator. That regulator consisted mainly of a single transistor and should be immmune to frequency variations.

At any rate, the highest voltage I have seen ny Force engines put out at full throttle is about 17 volts. Might be within the range acceptable to your electronics.

The alternator only delivers about 7-10 amps (at WOT not idle) so you can use many light current accessories like beer cooler, air conditioner, 17 inch subwoofer on a 1,000 watt amplifier----LOL! Figure out what 7 amps will power then only use 1/2 to 3/4 to be on the safe side. I think you will find it won't be much more than a decent radio/disc player.
 

Mark42

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Re: 85hp - Change Rectifier for Regulator?

.... The alternator only delivers about 7-10 amps (at WOT not idle) so you can use many light current accessories like beer cooler, air conditioner, 17 inch subwoofer on a 1,000 watt amplifier----LOL! Figure out what 7 amps will power then only use 1/2 to 3/4 to be on the safe side. I think you will find it won't be much more than a decent radio/disc player.

DOH! I wanted to run a LCD DVD projector powerful enough to throw a movie on a 80 ft high sand dune.... Kind of like drive in movies on the bay... :)

Actually I'm addind some LED floor lighting, some LED dome lights in the cuddy, and some cigarette lighters for charging phones, radio, and (the big one) a roof mounted spot.
 

bertthedefender

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Re: 85hp - Change Rectifier for Regulator?

I replaced the faulty regulator/rectifier with the CDI/Rapair part on my 1991 70hp motor a few weeks ago - opening the throttle in neutral, the voltage at the battery went up to 16.7, but maybe thats normal.
 
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