Battery question - 40 amp charging system??

[skeeterboy]

Well finally replaced stator, power packs, and voltage regs and motor is running great, idling great, and turning 6000 rpm no problem.

Question is on my lowrance I have voltage readings and at idle or running speed I am getting 13.3 to 13.5 volts but when I turn on my livewell, bilge, and recirc pumps volts drop to 11.5.

Is this normal or is it possible the battery is getting weak. Also at the lower rpm (around idle) tach is not reading correctly (drops to zero).

Any help or suggestions appreciated...

Thanks,

John

1995 Merc. 200 efi

[j_martin]

Not battery, either charging components or wiring.

Ground is critical on the regulators.

John

[skeeterboy]

I cleaned all the grounds prior to my original post ( pain in the butt) but my cdi regs have no black ground wires.


Any suggestions???

[camrynekai]

Your flywheel magnets may be weak...a good strong flywheel will fight you when installing it and trying to align the keyway...it should want suck down to the stator with vengeance and take some effort to position it. My 15 year old flywheel was so weak compared to a new one and was a breeze to remove and install...the new one was so strong it almost took my finger tips off while I was installing it and I had to use a few muscles to position it on the crank.

[j_martin]

I cleaned all the grounds prior to my original post ( pain in the butt) but my cdi regs have no black ground wires.


Any suggestions???

Star washers under the mounting screws, and be sure the mounting plate is grounded well.

[j_martin]

Wiring

[gfinch]

What does it read at the battery. I've seen the same "low voltage" and at the battery it was fine.
Most Wiring in boats have a lot of voltage drop. Lots of corrosion at terminals and on the wire itself. One has to remember we don't have the body(as in a car)as the other wire. What I have read is the wire size should be figured as twice the length because of this.

[j_martin]

Gary has a point. If everything is pulling off the same relatively light wire, and your dash voltmeter is on that same circuit, it's going to read the voltage at the end of that wire, which may have taken a coupla volt drop.

So troubleshoot, starting at the battery. If it's good there, then find out why it's deficient under the dash. Might just be you have to replace a 16 g feed with a 12g.

Ground return must be heavy also.

hope it helps
John

[skeeterboy]

I pulled some more wires and cleaned them at the terminals. I will do the battery test next time I run the boat.... I cleaned all the grounds prior to installing the stator, packs, and regs and you talk about tedious and time consuming....

Anyone that is reading this know WHAT the actual voltage should be when running????

Thanks,
John

[rprinzo]

had the same "problem"?non problem. went from 9" graphs to 12" graphs and was reading low volts on the front and just a little better at the console. installed new battery, still low. ran new 10awg wiring to both straight from battery and tada!!! reading 13.7 all day

[Stoker boy]

When the tech starts acting weird replace your rectifier.

[Smalltownbassin]

I pulled some more wires and cleaned them at the terminals. I will do the battery test next time I run the boat.... I cleaned all the grounds prior to installing the stator, packs, and regs and you talk about tedious and time consuming....

Anyone that is reading this know WHAT the actual voltage should be when running????

Thanks,
John

14V...ish.

[keefallan]

Y'all realize this thread is over ten years old.

[mrichartz]

Hey better late than never..