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We have a 2003 90 HP Mercury 2 Cycle on a 1973 Cohasset. Last Wednesday, the voltage regulator shorted out, creating a nasty stink, much smoke, and a potentially bad fire under the cowl. The Mercury mechanics/technicians we consulted were not surprised, saying "Yep. This happens. You would have noticed it going bad if you had a tachometer or a voltmeter installed". So, my question for you Mercury guys is, who's had problems with votage regulators, and what do you do about it?

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Pardon the dumb question from someone that doesn't know anything about outboards, but what would would the gauges indicate if this problem existed?

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I don't think you can do much about it.

How much are they?
Do they have a superseded version that has been improved?

There are two things most of us wouldn't be without on our boats.
1. Tachometer
2. Voltmeter

If there isn't a voltmeter onboard, how do we know our charging system is working?

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In many cases a voltage regulator or rectifier that is failing will cause the tachometer to be showing varied readings at constant speed. In many cases owners think there tachometer is broken.

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Joe, is there a standard volt reading that indicates the batteries are charging correctly? For example, I have a 1986 Mercury 90HP, should I be looking for a certain readout with that engine?

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OK, so now I'm more interested. If the voltage regulator goes out and the tach needle moves around at constant speed, then does the voltmeter show zero charge? My 1997 Merc (2 stroke, 75 hp) tach jumps around or shows higher than actual rpms at constant speed but the voltmeter still shows the engine is charging. Sorry if this is off track, I don't mean to "hijack" this thread, but I don't want a short and engine fire if I can avoid it.

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The short answer is that since 1959, in any boat, we've never had a voltmeter or a tach. Not that this is the correct answer - just the truth. We're primitive, I guess. I'll probably add the voltmeter on my next trip north. Cost in northern Ontario where we keep the boat was $ 285.00 plus PST, GST & HST. So it's a little pricey to keep one layiong around as a spare. Thank you all for the sound advice.

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Gmondun,

When it is charging properly, the gauge should show around 14 volts (in the Green) on these gauges I show below which are OMC.
http://www.whalercentral.com/articles...icle_id=43

benhowes,
Ouch. Expensive Voltage Regulator.
Hopefully you could find one online cheaper.

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Thanks Joe. I'm gonna double check my reading next time I'm on the water.

Gordon

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I would not bother with an old fashioned 2" volt meter gauge. Virtually all marine electronics that are had wired to your boat like a fishfinder, depth sounder, GPS, chart plotter all have a volt meter function built into them to help you keep on eye on your charging system.