How to read an am meter

You should get a positive reading. A negative reading would indicate your battery is doing all the work.

Reading the ammeter can be a bit tricky. What you have to remember is that the more amps your alternator is putting out the higher the ammeter will read in the positive direction. This means that if your battery is discharged, it will pull more current from the alternator making the ammeter read higher (in the + direction). Likewise, a fully charged battery will draw little from the alternator and the ammeter will not read much above the neutral position. Volt meters are best for telling a true indication of your overall charging system. They also require a much shorter charger circuit meaning less voltage loss between the alternator and the battery. Converting is very easy and in my opinion very worthwhile.

I was thinking aobut putting a volt meter in my '79. If the conversion is easy, then could someone detail out the steps.

Kevin's '79 wrote: I was thinking aobut putting a volt meter in my '79. If the conversion is easy, then could someone detail out the steps.

Its not so much steps as much as it is a difference in wire configuration. The following pic has the wiring for PCM engines and provides volt meter and ammeter options

http://www.skiboathelp.com/tech/colorcode.html

Wow, I agree with 79!

Anyway, to me, the ammeter is the better of the two gauges just for the reasons 79 mentioned. To me, the voltmeter is only useful in telling me that my battery has 12 or more volts.

The big problem with the ammeter is the heavy electrical current flowing from the alternator through the gauge and back to the battery thus requiring a heavy gauge wire and very good connections. The volt meter only requires a light gauge wire with minimal current.

I view the volt meter as useless because when a real problem is evident by the gauge, you are SOL.

Page 20 of the PCM service manual referenced on this website states a preference for the volt meter as follows:

1. By simply turning on the ignition key for a moment, it is possible to tell the charge condition of your battery.

2. By enabling the alternator output to shunt directly to the battery, rather than all the way to the instrument panel and back, there is virtually no current loss or line drop. In installations requiring an unusually long harness, such as houseboats, this is especially desirable.

3. Any overcharging tendency can be readily detected as an abnormally high voltage reading on the voltmeter, and corrections can be made before battery damage occurs.

I dont know which is better. I guess its simply what your comfortable with

You say say "tomatoes" I say "tomahtoes". Both ammeters and volt meters are valuable. It seems to me that people with an understanding of the electrical system prefer an ammeter - others a volt meter - I guess because the volt meter indicates a level of "good" vs "bad"? My girlfriend prefers an idiot light and for her I do too.

I suggest you keep what ever comes in the boat and learn how to understand what it is indicating.

BTW, for anyone who cares, I prefer an ammeter if I have to choose one over the other. I feel warm and fuzzy when I see my alternator throwing out all kinds of amps when needed. ("All kinds" is as accurate as my ammeter is capabile of indicating). It's easy to throw a volt meter on the battery at any time. It's a little difficult to "throw on" an ammeter.

Is the subject of this thread drifting?

Typically right after starting the engine the ammeter should read to the positive (+) side. After a few minutes and the battery recieves a charge, the needle should come down almost, I say "ALMOST" to zero. Sometimes you have to look really really close to see that the needle is not quite right straight up on zero. It should never point to the left negative (-) while running.

If, right after starting, your ammeter is still on zero or slightly negative you have a problem - don't leave the dock without a paddle. Or, if you have a lot of riders take along a lot of paddles. They'll be impressed that you planned ahead and they'll think that you know what you are doing - even if your boat doesn't run.

Your boat has a lighter?

Man, they just put all kinds of frills on these new boats.

As a follow up, and on a slightly differnet note, I notice that 79, above, has 1197 posts and still has only 3 stars. What does it take to get 4 stars? And, what is the classification above "Senior Member"?

"Should be dead and buried member"?
"Senile Member"?
"Old as ShxT member"? (Notice I circumvented the *)

In case your wondering, I just popped the cork on a new bottle fo cold white wine and it got me to thinking.... being primariy a red wine drinker I may have to reconsider my whole life.

What I do know is right now, it is just too dark to untie the '68. But, I think I may just go sit in the boat, fire it up, and listen to the 40 year old 289 rumble while I consider the ups and downs of piston travel - at least until the wine runs out... nighty nite all.