Cattitude

My new to me Daytona appears to have one battery separately rigged for each engine. I want to redo it with a master switch so I can have both engines see one, the other or both batteries. Does anyone have a schematic- or does it come with the perko type switch when i buy it?

Reed Jensen

The switches come usually come with a schematic. But... most people forget that if you want to be able to switch the power from one battery to the other engine... you MUST have a ground cable that connects both engine blocks together.

Cattitude

good point- taken

Wally

iTrader: (1)

you want to do this with one switch??? I dont think you can do it cause the alternators will be fighting each other when both running.....
Idealy you need two switches...

Reed Jensen

You are correct Wally. To do what he wants to do... he must have two master switches.

bowtie

Two switches, go from #1 lug on each switch to that engines battery. Run a jumper between the #2 lugs on each switch. Keep each switch on #1 unless you want to parallel batteries, then go to all. And of course the ground cable mentioned above.

Cattitude

Thanks- wouldn't have thought that....... but that's why i asked I'm no elcetricity guru. I thought of it as filling a tank(batteries) from two different buckets (alternators).

This is my first twin boat- are they usually rigged with two switches and two batteries? Thing is, If one battery dumps (or the stereo gets played too long) you need to fire both engines to get back.

HiPerf2000

iTrader: (2)

So both switches should be set to #1 when not wanting to run in parallel ??....rather than one being on #1 and one being on #2 ?

If one switch is on #1 and the other on #2, does that mean that the one battery is never getting charged ?

bowtie

No, the port switch uses the port battery as #1 and the stbd switch uses the stbd battery as #1. Port engine charges port battery and the stbd engine charges the stbd battery.

Reed Jensen

My switches were set up with the Port Battery as #1 and the Starboard battery as #2. The switches are fabricated with two terminals for batteries... one terminal for the starter. So under normal conditions to start the engines you would have the Port switch set on #1 and the Strbd switch set on #2... The numbers designate the batteries.... not the engines. During mooring you can turn the port battery switch to "off" and leave the strbd switch to #2. Then if the starboard (#2) battery goes dead from stereo and accessories... you put both switches to #1 and start the engines. But... keep in mind... You have to be very careful about how the boat is wired. If any accessories are cross wired or the batteries are "bridged" somewhere downstream in the wiring... having two switches won't isolate the batteries. When I wired my boat from the stem to the stern... I was very careful about isolating both charging systems. The port battery and alternator fed only the port gauges and trim motors. The starboard battery and alternator fed the right gauges, trim pumps, dash lighting and all accessories for the boat such as stereo and cabin lighting. So when I turned the port battery switch to "off". That battery wasn't feeding anything. I could run the Strbd battery dead and still have one fully charged battery for starting. But... If I had cross wired one accessory or bridged the wiring under the dash, both batteries wouldn't have charged seperately.