Author Topic: Boat Batteries  (Read 11071 times)

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Offline tomw

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Re: Boat Batteries
« Reply #15 on: March 26, 2012, 05:00:59 pm »
Chris;

Don't tell me you don't have a way to cut AL to make an access hole? :o

Anyway, if you get at doing it be sure to grease the cable on the end it feeds from. Like other things in a guys  life when it is a tight fit you need some lube to slip it in easier!  8)

Or not.

Good luck with it.

Tom
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Offline ChrisOlson

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Re: Boat Batteries
« Reply #16 on: March 26, 2012, 06:16:03 pm »
Oh, I got the technology and equipment to make all sorts of access holes.  The problem is pluggin' 'em shut after I get done accessing.

I went to the marina today and bought a new switch panel for the boat that has dual bus feed for 24 volt marine systems:



I talked to the service people and it turns out the salesman was full of bungus.  A boat with a 24 volt system is still 12 volt.  The trolling motor plug has three pins for a reason - one is ground, one is 12V to ground, the other is 24V to ground.  You can plug either a 12 or 24 volt trolling motor into the same plug and either one works.

During operation one battery in the bank powers bilge pump, and livewell pump.  The other powers nav, anchor and cabin lighting.  And both power the 24 volt trolling motor.  The bank gets unbalanced during a day of fishing.  But that's why marine battery chargers have two more more channels that charge each battery in a 24 or 36 volt bank separately.

We already got a MinnKota MK210D dual channel charger for 24 volt that I bought and put in the boat a couple years ago:

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So we're all set - all I have to do is rewire the whole boat   ;D
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Offline ChrisOlson

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Re: Boat Batteries
« Reply #17 on: March 27, 2012, 09:02:50 pm »
Well, the boat saga continues.  She's getting all the upgrades - electronics, 24 volt, and new trolling motor.  I had to order a 24 volt trolling motor.

The reason the deep cycles are up front of the main deck is because of a couple reasons.  I altered the port timing a bit when I put the new reed block in it, and then I did some more work on the exhaust ports when I had to replace the exhaust baffle.  Plus I put a stainless prop on it a few years back.  It probably puts out closer to 50 hp at the prop shaft, although I've never dyno'd it.  But it does turn up to 6,800 rpm and it's only supposed to run at 6,000.

The problem is that it's got too much power and it launches the boat right out of the water even with full down trim.  It porpoised really bad and you couldn't even run it at full throttle.

So I moved the deep cycles up front and stow the anchor in the forward storage compartment to add weight to the front of the boat.  With that change she trims out really nice and runs like a banshee.  It will cavitate the prop sometimes if you crank it wide open on a launch out of the hole when the boat jumps out of the water and up on plane.  But if you ease off the throttle a bit to get the prop to hook up again, then go back to wide open throttle you can bump the trim up a tiny bit to get an extra couple mph out of it.  When it starts to go into a porpoise, give it a nudge of down trim and she's right and she runs.

We get a lot of rubber neckers when they see a tiller boat running up the lake at 40 mph throwing a 50 foot rooster tail.  But hey, your equipment has to perform    ;D

I could get a couple more mph out of it if I could get rid of that whale fin on the cavitation plate.  But without that there's not enough lift on the stern even with full down trim, being the boat is stern heavy.  Even with the batteries and anchor up front the boat still goes into a porpoise without it.

All the latest updates:


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Offline ChrisOlson

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Re: Boat Batteries
« Reply #18 on: March 28, 2012, 12:34:22 pm »
This boat wiring doesn't make sense.  The boat was designed to have the batteries in the stern under the splash deck.  Then the power to the trolling motor is fed thru those wires in the conduit under the deck up to the bow.

Since I had to move my batteries to the front of the main deck it makes more sense to me to re-do all this.  I can drill the rivets out of the forward deck and pull the deck up.  Then put another conduit under there from the batteries to the bow for the trolling motor.  That way it's only 6 feet of wire from the batteries to the trolling motor, which is the heaviest electrical load in the boat.

The way it is now, there's two #2 cables that run from the trolling battery bank for 14 feet to the stern to the power bus.  Then another 18 feet of #10 in that conduit to the bow for the motor.  So the power to the motor is running thru 32 feet of wire.

My theory is that I can feed the power the 6 feet to the motor right from the batteries.  Then use the #10's in the conduit under the deck to feed one ground and two 12 volts (off each battery in the bank) from the bow back to the stern, to the power bus, to run the rest of the lighter loads in the boat.  With everything turned on in the boat (besides the trolling motor) the total amp draw is around 10 amps.  #10 is plenty big enough for that.
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Offline ChrisOlson

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Re: Boat Batteries
« Reply #19 on: March 28, 2012, 11:59:50 pm »
If you decide to rewire your boat, you may as well just buy a different boat.  Turns out none of the wire in that boat is copper.  It's some sort of marine grade tinned wire with insulation that meets Coast Guard spec blah, blah, blah.

The only way the marina sells it is on a 100 foot spool - $140 for 10 gauge.  And then you only get one color.  If you want two colors (red and black) then it's $280.

No wonder boats are so damn expensive.
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Chris

Offline rossw

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Re: Boat Batteries
« Reply #20 on: March 29, 2012, 12:04:14 am »
The only way the marina sells it is on a 100 foot spool - $140 for 10 gauge.
....
No wonder boats are so damn expensive.

It's more likely because the people that run marinas think the people that run boats, are loaded.
And the people that supply to the marinas think that the marinas customers are loaded....

Make some calls, find someone else who sells the cable. There will be someone. I'd be surprised if you can't buy 4 spools from someone who doesn't think they have you reaching for your ankles, for the price of 1 from the marina.

Offline rossw

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Re: Boat Batteries
« Reply #21 on: March 29, 2012, 12:10:04 am »
Make some calls, find someone else who sells the cable. There will be someone. I'd be surprised if you can't buy 4 spools from someone who doesn't think they have you reaching for your ankles, for the price of 1 from the marina.

Just did a quick search on ebuy

http://tinyurl.com/7ov4s84

Twin Core Marine Grade Tinned 6mm Wire, one black one red, in a protective outer sheath for about the same price for 30 metres (100') as one spool.  10AWG is 5.2 sq mm, so this 6 sq mm cable is fractionally heavier.

Took me longer to write this than it took to find the listing....

Offline ksouers

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Re: Boat Batteries
« Reply #22 on: March 29, 2012, 05:14:46 am »
Chris,
I agree, boat wire is outragiously expensive. Way over priced for what it is. It is different than "regular" house wire. It's copper that has been tinned throughout its length and double insulated with UV resistant covering.

I just use commonly available wire on my sailboat without (too many) problems. And those problems I have had can almost always be traced to a poorly protected splice or connection. The best practice I've come up with is to solder all connections, seal with 3M 4200 marine adhesive and double heat shrink. Make sure you extend the 4200 well past the joint onto good insulation. Shrink the first layer of heat shrink on the 4200 while it's still wet and hasn't set up.

The insulation on some cheaper wire will leach water through it if its constantly wet. It also hardens and cracks over time. No UV necessary. The best is silicone double insulated but it's also expensive. Use silicone dielectric grease on all exposed terminal connections. It's messy but it works.

Remember, BOAT is an acronym:

Break Out Another Thousand!


Kevin
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Offline ghurd

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Re: Boat Batteries
« Reply #23 on: March 29, 2012, 08:38:46 am »
Some of the marine grade stuff has a coating of some kind of powder on the tinned wire making it a bugger to solder.
Wiping off the powder from all the strands makes it take solder a lot easier.
G-

Offline ChrisOlson

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Re: Boat Batteries
« Reply #24 on: March 29, 2012, 11:24:27 am »
I like to buy stuff locally whenever I can to support our local businesses.  They provide a lot of support and service on stuff when you need it.  The service people at the marina have already been helpful in giving me wiring diagrams on how to wire it up for 24 volts so it meets all the coast guard specs.  So I'll probably just spend the extra buck to get the wire from them.  The wire they got is really nice wire.  It's got a type of insulation that's really flexible, where the automotive primary wire I was going to use before I discovered this is really hard and stiff.  You can tell just by handling it that it's high buck, high quality wire and it says Ancor Marine Grade on it.

I put dielectric grease on all the terminals on the 24 volt switch panel I installed.  And there's a harness connector in there that connects the switch harness to the boat's main harness.  I put dielectric grease on all the pins in that connector too.  The pins in that connector looked like they're silver and they weren't corroded at all after 22 years.

I have to reconfigure the power bus in the stern for 24 volt.  So I'm going to remove the old 12 volt two strip one and replace that with a new three strip 24 volt bus.  The marina has a SeaSense 24 volt bus for $260 and it's a nice one with manual-reset push button breakers on all the circuits so I can get rid of the old glass fuses and stuff in there.  Those automotive style fuses are a problem on marine applications too because they corrode.  I've had to wiggle those sometimes to get lights to come on and stuff.  So it's time to replace all that too.l

Yep - I like Kevin's acronym for BOAT.  The trolling motor was $1,500.  The new Humminbird electronics are $2,000.  By the time I get done with this boat I'll have to Break Out Another Thousand a few times over.   :o

Edit: But, on the other hand, have you priced new boats lately?  A tiller boat is the only thing to have if you're serious about fishing on inland lakes.  Console steer boats, of the same hull length, don't have any deck space.  Alumacraft don't build the Backtroller anymore, but they got one that's similar to it - the Tournament Series, or whatever they call it now.  A boat like this new, with a 40 horse Merc Chink Motor on it, and equipped like I'm equipping this one, is almost $17 Grand.

So when fishing is the favorite thing that you and your wife like to do, you can afford to Break Out Another Thousand to upgrade an older boat.  If the hull don't leak, the transom is good, and she's structurally sound, it's not like it's going rust out, wear out, or the wheels fall off it like an old car.
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Offline ChrisOlson

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Re: Boat Batteries
« Reply #25 on: March 31, 2012, 02:02:52 pm »
Well, got everything wired up and it all tests out good.

I got some 80 VDC rated 90 amp breakers from Tom like this:
[ Guests cannot view attachments ]

I put one on the trolling motor battery bank - replaced the old inline marine fuse with it:
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Having a breaker on there is a lot easier to reset at 11:00 at night when you accidentally short something out on the trolling motor and the whole boat goes dead because the Main Fuse blew.

I also installed a battery selector switch so I can start the outboard from either the starting battery, or the one battery in the trolling bank that has this breaker on it.  The outboard starter draws 150 amps surge and 80 amps continuous during cranking.  That breaker handles starting the outboard off the trolling bank with ease, even with everything else in the boat turned on.

Works awesome - thanks Tom!

Got the Merc running after the new water pump installed.  Wanted to take the boat out on the Yellow River for a run today.  But it's cold - way too cold to take the boat out for a joy ride.  So I ran it with the muffs on it.

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Chris

Offline DBCollen

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Re: Boat Batteries
« Reply #26 on: April 01, 2012, 12:15:58 am »
I thought that breaker looked familliar, I sent some of those to Tom a few years ago. I only have a few hundred left  :)
Dustin.

Offline tomw

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Re: Boat Batteries
« Reply #27 on: April 01, 2012, 07:03:52 am »
I thought that breaker looked familliar, I sent some of those to Tom a few years ago. I only have a few hundred left  :)

I told you they would get used!

Bet you did not know they were Marine Rated[TM] !  :D :o 8)

Tom
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Offline ChrisOlson

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Re: Boat Batteries
« Reply #28 on: April 01, 2012, 04:08:32 pm »
Well, got to take 'er out for a joy ride on the Yellow River.  The boat didn't sink.  The motor didn't quit.  Just have to install my new trolling motor and electronics.  Then wait another month for fishing season to open   :o

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