Which position for the battery switch?

sk520

Question Rinker fans....we have a 2003 FV250 with a battery switch which has an "on..off..." and then two positions for "emergency start". Alot of posts talk about one or two batteries, whats the proper operation of this switch?

MarkB

The answer is, it depends on how they wired your switch. Really. My guess is that you should keep it on "on", but you need to confirm by checking where power is coming from in each position. The ideal is to keep it where the crank battery runs the engine only, and the deep cycle battery runs the house circuit only.

howardrams

Mark is correct.  Rinker's intent is that the "on" position is normal.  This feeds the engine stuff from the crank battery and the house accessories from the house battery.  Only in an emergency where your starter won't crank should you need to turn to the "combine batteries/emergency" position which adds the house battery to assist the dying crank battery.  This all assumes the factory wired things right, and nobody changed anything for their own purposes.

It is a good system which saved me once out in the middle of Lake Erie.  Enjoying a day of boating I was unaware a loose wire on my alternator meant my engine battery was slowing dying.  Eventually if I hit the trim or trim tab switch, my gauges all stopped working, and engine ran rough.  Back to normal when I stopped hitting those switches.  Pointing the boat back towards my dock an hour away I noticed the voltmeter reducing from over 14 down to 13, 12.5, etc., and the engine eventually died and would not crank.  So I went to "combine batteries/emergency" and she cranked right over and everything was back to normal, but I could tell the voltmeter was only reading battery voltage, so the alternator was not doing its job.  I felt I could make it back to the dock and I did.  I couldn't find the loose wire until I got back.  But the whole way the voltmeter was dropping gradually 13, 12,5, 12.

Once I found and tightened the wire, I was back to 14.5 on the voltmeter, and everything was fine for the rest of the season.

So, don't run all day in combined or emergency or you may not know you have a problem until both batteries have drained too low to crank the engine, or even keep it running. I must say although I am not a fan of the Faria instruments, in this case I was impressed by how accurately that voltmeter kept me aware of what was going on.

 

MarkB

The other reason you don't want to keep it on combined is often the crank and house battery are different types of batteries, and you ruin them by putting them together, even if in parallel.

Cableguy Greg

If you have the Blue Sea switch that states "Off, On, Emergency Start", it is a 2 circuit switch. When it is in the "On" position, it turns on both circuits independently and keeps the house and start battery circuits separate. When you move it to Emergency Start, it combines both circuits to start the engine, in other words, both batteries in parallel. The Guest switch that states "Off, 1, 2, 1+2" could be totally different. I just know about the Blue Sea switch.

Just like what happened to @howardrams, I got stuck on the river my first time out on my boat. The breakers were off, which I didn't know about, but I had enough power to start the boat, run 6 miles down river, then anchor via windless. My wife and I started exploring the boat, turning on lights, listening to the radio, ect. We then try to start the boat and it will barely turn. Had to use the Emergency Start to get her running and the anchor up. I found out really fast that the PO had shut off the breakers. Ugh... Since the Faria gauges aren't super accurate, I added VDC to my Lowerance display. I figured that 2 VDC readings are better than one. I also have made the habit of checking my battery breakers before I leave the dock.

Dan4754

I hope I'm not hijacking this thread but here goes:
The delivery orientation of our 2005 250 FL lasted all of 10 minutes. Almost every question was answered with, "look in the manuals". Needless to say, I did and am doing a lot of learning.
Our battery switch has A, B and emergency start. I do not know which is hotel or engine.
Do I need to choose a battery at the switch?
The only thing that is obvious to me is to NOT choose emergency.
Any and all info (even a link) will be welcome

howardrams

I've not seen that particular labeling, but here's how it worked on my older Rinker Fiesta Vee which was a single engine as it came from the factory.  Their earlier cruisers didn't really have a house or engine battery per se, but the 2 batteries were both starting batteries, not deep cycle type, basically in parallel and either battery could power the whole boat.  It didn't have near the accessories of today's models.  Basically your normal engine stuff, lights, a DC refrig, and water pump for the water to sink or shower stall.  That one, a 1992 model had the selector switch "Off", A, B, or A+B.  If you were anchored for the night away from any shore power, you would choose either your A battery or your B battery so you could drain just one of them with radio, lights, refrig, and anything you could plug into the cigar lighter.  Then in the morning you'd switch to the other, start your engine, and go.  But the owner was deciding which battery he was using as his "house" because the circuits were identical, and you'd want the other one as your reserve.  So you could run all the time in "A", or in "B", or in "A+B" based on your preference or intent.  A+B could certainly be used in an emergency, but they didn't label it that way back then.

So if you have just 2 batteries and neither one is a deep cycle, it could be neither is house, its just and either-or situation.

Dan4754

I'll have to double check the labeling.

I don't remember A+B being an option.

MarkB

Emergency start on a few boats seems to be the combined mode.