alternator switch?

[gearhead]

The alternator on my '73 Johnson 115 OB is non-regulated. Would there be any harm in using a switch and relay to allow manual control of charging by opening opening the rectifier output. Is there a way to remove power from the field instead?<br /><br />Thanks

 

[Trent]

Re: alternator switch?

This easy way is just to turn stuff on to load up the system and keep the battery topped off with fluid.<br /><br />Thousands of engines out their working fine this way.

 

[gearhead]

Re: alternator switch?

I have tried that but, the only way I can keep it under control is to work the trim motor. I don't have much in the way of other electric loads.

 

[gearhead]

Re: alternator switch?

^

 

[Trent]

Re: alternator switch?

They make a kit to install a regulator.

 

[oldboat1]

Re: alternator switch?

If you disrupt the rectifier output, you will burn up the rectifier. <br /><br />I think the alternator charges at 6 to 10 amps -- wouldn't think that would be a problem. I'm curious about the problem you are having. When operating the engine at speeds, the battery will probably show a charge on a voltmeter of 13 or 14 volts if it was fully charged to begin with. If you just keep the cells full (distilled water), I can't see there would be a problem.<br /><br />still curious....

 

[Franki]

Re: alternator switch?

Hi people..<br /><br />if its anything like my 100hp 72 johnson, its rated at 9 amps.. thats pretty low and under heavy load you could flatten your battery while running..<br /><br />if you are actually overcharging your battery and are worried about it, then you could add a big coil resistor to it (on a switch).. or even just a spotlight or two.. anything that will "take the edge off" but 9amps really isn't that much, the newer outboards seem to have a minimium of 20-40 amps.. and I was worried the other way, that maybe I will run flat while running at night with nav lights, spotty and fish finder etc.. so I added a solar panel to the roof of the cabin to make sure the battery got fully charged during daylight hours.<br /><br />I was wondering if there was a newer charging system that would fit this one...??? I'd like to get up to 20 amps and have a regulator..<br /><br />any ideas anyone??<br /><br />As for mr Gearhead. what makes you think you have a problem???<br /><br />regards<br /><br />Frank

 

[gearhead]

Re: alternator switch?

Having witnessed the damage that overcharging a battery can cause, I feel that some method of regulating the charge is needed. The only way that I have been able to keep the system voltage below 16 volts is to frequently run the trim up and down, turningon the bow lights and bilge pump has no effect. When out for a pleasure cruise this can be a real pain.

 

[almost retired again]

Re: alternator switch?

Hello Gearhead,<br />If you really want to switch it off put the switch in series on the yellow wire comming from the alternator, this will open the output of the alternator. Actually you could open either of the two wires the yellow or the yellow/grey wire. I've done this on a 60hp racing boat where it was benificial to reduce the drag caused by the alternator during raceing.