Voltage

[RioRat]

My voltage gauge on the dash shows under 13 volts while the boat is started.  The perfect pass confirms the voltage to be 12.8 volts.  The crazy thing is the faster the boat goes the lower the voltage reads on the perfect pass.  It actually dropped down to close to 11 volts.  As far as I know the alternator is still good because my battery never goes dead, however the voltage never reads even close to 13.8 volts.  Any thoughts??   I plan to bring a voltage meter next time out and take a reading at the alternator to see how much it's putting out.

[lilfoo2225]

take a reading at the battery first and see what that gets ya. should be charging over 12 with it idling. 12-14.

[sailtl]

I have had the exact same thing with our 99 Epic 21 although I never got to 11. I have lived with it so far but I may start digging into it this year.

[cyclone]

I posted on this a couple of years ago. You need to add a 10 ga. or 8 ga pair from the perko switch to the dash supply at the DECC switchbox. The factory 10 ga wire is too small and you get voltage drops at the dash. If PP goes below 10vdc it will turn off.

[sailtl]

I added the wiring a couple of years ago but it still does the voltage thing. I have never gone below 11.8 vdc.

[masonlk]

It's an oddity that I have also. 13.8 at idle and 11 or below at 6150 wot. I added the wiring a couple of years ago and it cured the eratic oil readings but seemed to only make a slight difference in the volt gauge so I have just lived with it. As long as I stay below about 4500 rpm I stay above 12 volts. It's never affected the battery and I rarely get into the higher rpm's anyway since the risk of spilling my margarita increases with the rpm's.

Let us know what you find with the meter.

[lilfoo2225]

lol! 

[Johnny B]

My SX does it too.  After I ran the new wires and added a second battery it got much better but at high RPM's it will drop and flash at me.  I just quit worrying about it because it always starts..

[RioRat]

The larger wire from the switch to the DECC at the dash makes sense.  I believe stock it is 12 AWG.  I have added a second battery (Yellow Top) and a battery isolator and I'm still surprised that it does this.  I still haven't used the meter, but I'll be sure to let you all know what I come up with.  I may just change the wires for the heck of it too.  Although, I would think 12 AWG would be plenty of wire for 13.8 Amps of current.

[cyclone]

The gauges have all the same problems that Kaiser Medallion gauges have on other boats of the era. On both my Epics, I ran an 8 gauge pair from the batt to the DECC switchbox posts. This clears up 90% of the voltage fluctuation and prevents the alarm but that reading is coming through the MDDC. I have not had to run bigger wires to the MDDC on either boat. I think that the first thing I would do would be to check and clean the connectors on the MDDC very carefully.

I run most of my accessories off the 8 gauge pair straight from the batt instead of through the factory 12vdc supply. I use the decc to switch relays to turn my amps on.

I did notice that the voltage as shown on my PP is higher than that of the dash gauge. That's what I use as a reference.

[Johnny B]

I added a second deep cycle battery when I did the new wiring and it helped a lot.  ( the wire hanging is a battery charger..)