My cousin turned me onto this idea, and I found lots of info on it on other forums. All discussed adding the actual yamaha part required to do it, and what has not been stated by anyone much is that doing that is totally unnecessary and a waste of money.
There is an isolated auxilary charging lead under your cowling made to hook up to an “accessories” battery isolated from your “starter” battery.
It is in the front of F150’s that I’ve seen, and it is on the starboard side of my Z200 (HPDI). To my knowledge most larger Yamaha’s have this after about year 2000. Some OX66’s may have it, but I am not sure if it’s an isolated lead. If your fuse box has a fuse for an auxilliary lead that’s separate from the main charging lead, then I would guess you’ve got one that will isolate your circuits.
The cable is red, and has a black connector with yellow plug in it.
Yamaha sells a cable that will plug into it, but it is a bit overpriced IMO. I simply ran some 6 gauge from the motor to the house battery ($12.00) and fused it with a 50 amp fuse assembly ($20.00).
There is an 80 amp fuse in the motor fuse box that’s labeled “isolated charging lead,” but that is well over what a 6 gauge cable can handle- also well over the 45amp rated output of the motor according to the manual. Apparently, the 80 amp fuse in the fuse box is for a reason unbeknownst to me, so I am not going to replace it with a lower rated one. The yamaha wire supplied with the connector and plug appears to be only 8 gauge, and I know from a friend who bought the actual Yamaha auxilliary charging cable that it comes with a mere 50 amp fuse on it. I would just copy this if I were you… except that a 6 gauge cable is actually a bit heavier than what yamaha sells you!
I just cut the connector off and spliced in my 6 gauge that runs to the House battery. The motor charges the starter circuit first, and then t
very true phin
only thing I dont think is accuratte, is that it charges 1 first, then the other. I am pretty sure it splits the charge rate equally
if you only have 1 battery, it charges at say 20 amps per hour
if you use the isolator charge wire, it charges 10 APH to both batteries
could be wrong, but pretty sure thats what they taught us in yammie school
regardless, its definately the way to go for a starting battery and a house battery
very true phin
only thing I dont think is accuratte, is that it charges 1 first, then the other. I am pretty sure it splits the charge rate equally
if you only have 1 battery, it charges at say 20 amps per hour
if you use the isolator charge wire, it charges 10 APH to both batteries
could be wrong, but pretty sure thats what they taught us in yammie school
regardless, its definately the way to go for a starting battery and a house battery
Hmmmmmm.
I can live with that. I would think that when one battery is full, then it will send more amps to the discharged battery than simply half the motor’s output. I hope.
NOpe, I think his yamaha is like my suzuki… It will actually charge Start first then house. Perko is only an on off switch… no charging help need a VSR if your engine doesn’t have the same charging circuit setup…
“The Wet Dream”
20’ Pioneer 197
150hp Suzuki 4-Stroke
no
a perko would allow you to charge whatever battery is selected, but that also means whatever battery is selected is the one being discharged.
with the yamaha built in isolator, your house battery can stay dedicated to house and the starting stays only for starting.
you could completely drain the house battery with say a stereo, and the starting battery would stay fully charged. it does this without your assistance.
Charge It
Your outboard’s charging system can recharge more
than one battery during the course of a typical
boating trip. But how does the engine know which
battery to send the electricity to?
Yamaha offers a Battery Isolator System to help make
sure the cranking battery isn’t depleted by the boat’s
accessories (which could happen if the house battery
was low on juice – the accessories would then rob
energy from the cranking battery.
Here’s how the Yamaha Battery Isolator System
works: after the engine is started, the battery with
the lowest charge receives most of the charging
system’s output. When both batteries have been
brought up to the same charge level, each battery
gets equal amounts of electricity from the outboard’s
charging system.
Very interesting and informative post.
I had no idea my 150 could be configured this way.
However, that said, in my case I plan to stick with my existing setup of two starting batteries-Optimas-and a Perko switch as I have a minimal amount of electronic gear on board and my main concern is insuring the motor will start when I need it.
Now, if I can just figure our a way to remind myself to switch the Perko:dizzy_face:
Oh, wait a second, how about using Phin’s suggestion?
Without automatic battery isolation, you can run all your batteries dead unknowingly as your motor is sitting there running all day and you think you’re charging them. Like Chris said, you have to have the perko switched to a battery if you want it charged. No way to know what battery’s got what charge, and you have to start on a battery and then stay switched away from that one all day to isolate it and be sure you have a hot battery waiting in reserve all day.
Most people do what I used to and switch to ALL whenever the engine’s running. Big mistake. The charging system on your motor may go out like it did on mine, and as soon as you cut the motor off for a second for the first time all day, you won’t be able to crank back. Had my perko switch on “ALL” for the entire day on this trip, and had to wait on sea tow while I sat on anchor 40 miles offshore. http://old.charlestonfishing.com/forum/topic.asp?TOPIC_ID=99709
Isolate a starting battery from your other stuff- I’m telling you it’s the best thing you can do on your boat electrically wise. Very cheaply done if you’ve got a Yamaha like above (or Suzuki it sounds like).
I never have used the “All” selection thanks to the folks at Seel’s who told me the 150’s generator is not strong enough to charge both batteries at once.
Usually use one battery going out and switch to the other coming home.
Sort of half-arsed way to ensure charging; but it has worked well for me.
I never have used the “All” selection thanks to the folks at Seel’s who told me the 150’s generator is not strong enough to charge both batteries at once.
Usually use one battery going out and switch to the other coming home.
Sort of half-arsed way to ensure charging; but it has worked well for me.
Sea Hunt 2002
Yamaha 150
The problem comes in when your motor’s charging system craps the bed. I never expected that to happen either, but it did- and it was at the worst time- on an offshore trip. I have two AGM Deka batteries. High dollar stuff… it doesn’t matter. I had a 600 watt sonar, 800gph livewell pump and everything else killing both batteries all day long as I ran the motor with the switch on ALL thinking they were charging.
Doesn’t matter if you never put it on ALL if you switch in the middle of the day. It has the same effect of either discharging or charging both by the end of the day.
When your motor ever stops charging, what you are doing with your battery selection will discharge both batteries by the end of the day as you’re assuming they’re getting charged up like I used to assume would always happen. If there’s no charge output from the motor, then what you will have done by the end of the day is discharge both your batteries!
A good idea with a Perko may be to always start on one battery… if it turns over strong, then you know that’s a hot battery… switch immediately to the other battery before leaving the ramp/dock to keep that hot battery you just started on isolated in reserve all day long. Never switch back until you need the juice. This way there’s nothing to remember to do past switching after startup.
Of course put a charger on both batteries at home after each trip to make sure they’re full when the
if you use the blue sea systems 5111e switch, it is an on/off/combined switch which isolates 2 batteries into 2 separate circuits. When the switch is ON you can start from one battery and all other electronics run off battery 2 (House) If you use this in conjunction with a VSR or your motors automatic charging circuit then your start battery will always be charged first, leave the battery switch in the on position all you want your start battery will never drain. Also if you need a few extra amps you can switch to combined to get started which parallells the circuit for extra cca. There are 4 terminals on the back of this switch…
“The Wet Dream”
20’ Pioneer 197
150hp Suzuki 4-Stroke
