New voltage regulator

I recently had an issue were the ground wires on all my gauges in the lower station melted so we traced it back to a shorted voltage regulator
We replaced the burnt wires installed another voltage regulator and a tested presto lite alternator
No smoke show but the system at both stations shows charging to be 14 volts low idle and 16.5 bouncing to 16 at higher rpms
This is a twin 5.7 omc Tolly http://www.hightail.com/download/el...pWUThUQw?cid=tx-02002207340200000000&s=191025
Any ideas
I'm afraid to run it with that much charging

I ran into a similar problem last year when the voltage regulator (Balmar MC-614) sense wire was connected to the house bank and the alternator was directly charging the start bank. Since the two banks were combined through an ACR, the ACR would not combine the banks until it saw at least 13.6 volts for a short time on one bank. The voltage regulator sensing from the house bank did not see the charging output to the start bank as the ACR had not combined the two battery banks. Since it didn't see any result of charging it kept ratcheting up the output peaking around 16 volts exceeding the upper voltage limit on the ACR. I shut it down pretty quickly while I thought it through. Since I had done the installation myself, I was pretty sure the sense wire was in the wrong place even though that was how the mechanic said to do it. It took me a couple of minutes to move it and that solved the problem. It only occurred when the house bank had been drawn down below 80%. I never did understand why it happened that way, but moving the sense wire solved it.

Tom

Are those voltage numbers from the gauge w/ fried wiring? I would check w/ a different meter to confirm. If those numbers are accurate the regulator is the the one giving orders, the alternator just follows them.

Good luck,

Rafe

ballast resistor removed,pertronix ign

Can removing a ballast resistor and installing a internal resistor coil cause issues with my charging system
Im getting 16.5 volts at the meter and very concerned but cant find the issue
Prestolite alt with automotive voltage regulator. starting battery charging from this alternator
I read that the ballast can cause charging issues but was toldto remove it and buy another coil with internal resistor so purchased a gm auto coil
Any help would be great

The Pertronix Ignitor system is designed to work with a 40,000V Flamethrower coil which has 1.5 ohms internal resistance. It will also work with conventional/stock coils if the resistance and output is similar. If you have an Ignitor II system, the proper coil is a matching 45,000V Flamethrower II coil with 0.6 ohms internal resistance.

If you have another coil designed for use with an external resistor, it should never be run without the resistor. The coil should only receive full voltage when the starter is engaged. I can't see how a correctly installed ballast resistor on the ignition coil could cause the alternator to charge at those excessive levels.

Here is a Prestolite troubleshooting flowchart that you might find helpful. Charging voltages as high as you are experiencing are not normal with a healthy, charged flooded call battery, and would indicate a failing regulator. Operating at the 16-16.5 V level will damage the batteries and is hard on the rest of your electrical system. Generally, 14.2 volts is thought to be the ideal charging voltage from a healthy alternator into flooded cell batteries. Other battery types might have other ideal charging voltages that might be better accomplished with more sophisticated external regulators.

Good luck.

Not sure I like the sound of a "flamethrower" coil with a gas engine. Just a brand name?

Bruce,

That's funny! Actually, PerTronix make high-quality ignition components and were one of the first to make modules to convert conventional points and condenser ignition to electronic systems. I would guess the "Flamethrower" name came from the higher voltages and I suppose the hotter spark generated by the system. The offroad/marine coils are epoxy filled which prevents internal shorting from vibration, and is non corrosive. Very reliable units.

Somehow, 'Flamethrower" and "Gas Fumes" in the same sentence do make you think twice . . . .

Fix maybe

LarryM said:

Bruce,

That's funny! Actually, PerTronix make high-quality ignition components and were one of the first to make modules to convert conventional points and condenser ignition to electronic systems. I would guess the "Flamethrower" name came from the higher voltages and I suppose the hotter spark generated by the system. The offroad/marine coils are epoxy filled which prevents internal shorting from vibration, and is non corrosive. Very reliable units.

Somehow, 'Flamethrower" and "Gas Fumes" in the same sentence do make you think twice . . . .

Click to expand...

I found a ground wire off the battery isolator and reconnected and had a steady 13 volts
Could this have cause my high charge voltage
Thanks for all the help

The good old RV $17.00 merge relay solves most problems with 1/10 the cost and perhaps 1/100 the complexity of yachty marine >solutions<.

normal charge rate

FF said:

The good old RV $17.00 merge relay solves most problems with 1/10 the cost and perhaps 1/100 the complexity of yachty marine >solutions<.

Click to expand...

Im not sure my problem is solved so another question
Should I be concerned that the charge voltage is around 13.7 idle and peaks at 14.7 cruise
My start batterys are fully charged and the 8 6 volt golf carts are charged via the in house charger so why would the the charge be that high?
It seems my old gauges read about 1 volt above my meter but it is a 1975 boat
Thanks

First off, make sure your measurements are accurate. I am assuming the voltages you reported were measured with an accurate voltmeter, and not the old gauges?

Now, back to basics. The charging output of the alternator is controlled by a voltage regulator, either internal or external. Since the 1980s most voltage regulators are solid-state and use transistors to control charging output.

The actual output voltage produced by the alternator will vary depending on temperature and load, but will typically be about 1.5 to 2 volts higher than battery or battery bank voltage that the regulator 'sees' at its connection to the battery. At idle, most charging systems will produce between 13.8 to 15.3 volts with no loads on the system. This is measured by connecting the positive (+) and negative (-) test leads of a voltmeter to the battery posts while the engine is running.

Most alternators that are charging properly should produce a voltage of about 13.8 to 14.2 volts at idle with no loads on the system. Always refer to the manufacturer's literature to be sure. Some Asian systems have higher charging voltages of up to 15 volts.

When the engine is first started, the charging voltage should rise quickly to about 2 volts above the base battery voltage, then taper off, leveling out at the specified voltage.

The exact charging voltage will vary according to the battery's state of charge, the load on the electrical system and the temperature. The lower the temperature the higher the charging voltage, and the higher the temperature the lower the charging voltage. The 'normal' charging voltage on a typical application might be 13.9 to 15.1 volts at 77 degrees F. But, at 20 degrees below zero the charging voltage might be 14.9 to 15.8 volts. On a hot engine in a hot engine room, the normal charging voltage might drop to 13.5 to 14.3 volts. These numbers are all based upon fully charged batteries in good condition. You can see how important it is to have a reliable, accurate voltmeter to troubleshoot the system.

You really need to get the manufacturer's specifications for your specific alternator, and regulator if it is external. Just do a Google search for the make and model numbers and I'm sure you will quickly find the information you are looking for. The engine owner's manual is another good source of information.

Good luck

LarryM
m/v Boomarang

Yep Back to the basics That's a great post and makes me feel better
I was concerned about the dash gauges reading close to 16 volts but my multi meter is more accurate but I will try another test before I decide
A vert good test on all the old battery's will start this week end
Thanks

IF purchasing a new 3 stage regulator , be sure to include the temperature sensor option.

It should be installed 2/3 up on the side of a batt case.

IF purchasing a new 3 stage regulator , be sure to include the temperature sensor option.

It should be installed 2/3 up on the side of a batt case.

Click to expand...

Yes, on the temperature sensor but different manufacturers have different mounting locations for their temperature sensors.

Ample Power's voltage regulators have the battery temperature sensor mounted on the positive battery terminal. Balmar's mounts on the negative terminal. Blamar also has an optional temperature sensor for the alternator that mounts on the alternator case. We have an Outback inverter/charger and the temperature sensor mounts on the side of the battery as mentioned.