Battery Location: 175, & Other Questions

[CTsalt12]

Hi All,

I am in the process of mounting a Minn Kota Riptide 70 lb on my 175.  I have a few questions.  You'll see how it's mounted in the picture.  I will be cutting the bow rails in the taped off area and adding a sliding rail sheath like the popular BoatUS article.

I am really on the fence as to where to put the two 60 lb batteries.  My first thought was to put them in the hatch I have the arrow pointing to.  The issue here is that it's not flat in there, and I'll have to build a wedge/brace in that hatch.  It also shifts the weight forward.  The boat still self bails just fine, so I haven't decided if this is a good thing or not.  It's also an area that will be bouncing around a lot in a chop.  Is this bad for my batteries? 

My next options would be to mount them in the stern, below deck, under the storage boxes in the stern corner.  The issue here is more distance between motor and batteries, more weight in the stern which leads to more wet feet.  However, there is no brace needed, and it's a stabile area for the batteries and no loss of storage.    What do you guys think??  The console is not an option for me as I have 2 batteries in there already, and i use the rest of it for precious dry storage.

Additionally, I'm struggling to grapple with the concept of onboard chargers vs portable chargers.  As far as I can tell, the only difference is that onboard chargers stay on your boat, are permanently connected to your batteries.  They both have to be plugged into a power source right?  Any recommendations for good chargers that will recharge 2 12V's overnight??  How much Amperage will I need? 

Appreciate the help as I'm clearly clueless here.

[boatnamesue]

Why do you need a 4th battery?  You've got 2 already, i assume 1 for engine and 1 for accessories.  All you need is a 3rd battery to run your 24v trolling motor.  You take the 2 accessory batteries and connect into a series by bridging a wire from the positive terminal of one to the negative terminal of the other.  Its a good idea to have a 50-60 amp fuse on positive nearest battery. 

All other accessories (nav, bilge, baitwell, etc) can still be powered and grounded from either of these 2 batteries. 

On board charger is easiest because you can charge the 2 accessory batteries at the same time.  Otherwise with the standard 12v charger you'll need to disconnect the series bridge and charge each battery separate.  If you're hoping to charge both batteries overnight using a standard 12v charger you'll need 2 chargers. 

Personally I wouldn't keep a battery, let alone 2 batteries, in a bow compartment because the bow takes a lot of pounding.  Unlikely a battery will explode, but it is an explosive energy source. 

[Capt. Bob]

A couple of thoughts CT.

Having owned a 170, I realize space is at a premium. That stated,

First, while the bow does take a beating, batteries like AGM type are designed for such use. Think about a battery in an off road vehicle. They can get pounded pretty good too. Anyway, does your style boating take you offshore so as to encounter such pounding? Another thought is the cable size and length in relation to the power supply and the motor.

Second, while I don't own a trolling motor I personally would want a dedicated power source for it. While I would guess under the right conditions, you could get home on the trolling motor should your starting battery die

Still, running the trolling motor all you want without fear of possible adverse effect on other electrical systems is a "peace of mind" thing to my way of thinking. Since we have a few members who are running trolling motors, I'd be curious how many are using their "house" battery bank to power it. Hopefully, they will chime in.

Lastly, Pro Mariner makes multi bank battery chargers that would fit your need. I like the idea of an on-board charger that you just plug in and forget it. Depending on the state of discharge of your trolling batteries, they charge very quickly (relatively speaking). Of course the downside is that an on-board can't be used to charge say your wife's/girlfriend's car, motorcycle, riding tractor or any additional device due to it's location. That's why I drag my charger out to the boat but if someone died and made me King, I'd have both.

A lot to think about. Good luck.

[CTsalt12]

Appreciate the thoughts both.  My confusion about onboard chargers is totally cleared up now.

Unfortunately I did not buy AGM Batteries because of the heavy price tag ($220+!). 

I didn't think I could use my accessory battery for the trolling motor.  I don't think they are the right size either, Minn Kota and most resources recommend 2 group 31's with upwards of 100 AH, and that's way bigger than my starting/accessory batteries under the console, so it would be a mismatch with one 31 and one smaller house battery.  It would also mean routing from the console back to the stern through the rigging tube, then back up to the bow.  That's at least 25 feet of wire and I would need heavier gauge and more resistance.  As opposed to the 5 feet I would need if mounted in a wedge on the bow.

While I don't go offshore, we get a pretty good chop here in the Long Island sound.  2 footers in a rapid succession are not uncommon.  How much abuse can standard (Marine grade) deep cycle batteries stand up to?  I have battery boxes for them.  I am also considering using some kind of foam to mount them in and maybe absorb some shock.

Also-how necessary are the battery boxes anyway?  My thought was that they are used to keep out any moisture.  I do get some water in the far bow, mostly in the keel area from bilge drainage.  Because of shape of the boat, water seems to pool up in the keel in the center of the boat, and I pump it out when I have my bow up around 2200 RPMs.

[Capt. Bob]

One thought.
http://classicaquasport.com/smf/index.php?topic=9842.msg129255#msg129255

This is a great compromise but was put in place during the rebuild so....

Still, space is a premium and Group 31's weight about 70+ pounds IIRC.
The deep cycle flooded have larger plates in their construction which may help provide some additional resistance to the pounding. The use of a box(s) could help contain spillage (if it happens). Mounting in the back resolves the pounding and larger conductors reduce the voltage drop but then there's the additional 140 lbs in the stern.

[CTsalt12]

Very interesting Idea Bob..   I thought of that actually after seeing a recent thread about some storage in front of the consoles on 22's where they forgot/decided not to cut the access holes during the build.

https://classicaquasport.com/smf/index.php?topic=3268.0

It occurred to me that there should be space between the stringers in front of the console on a 175, that is being unused. Weight-wise, that would be a fantastic place to put them,and I could easily shoot the wires along the keel up to bow (I think?).  I will take some measurements and try to draw a straight line from where I can see the stringers in the stern to the bow.  The front hatch has notches for the stringers so I can line it up there as well.  While it is daunting to cut new hatches in the boat, and not optimal, fortune favors the bold right? 

[boatnamesue]

I didn't think I could use my accessory battery for the trolling motor.  I don't think they are the right size either, Minn Kota and most resources recommend 2 group 31's with upwards of 100 AH, and that's way bigger than my starting/accessory batteries under the console, so it would be a mismatch with one 31 and one smaller house battery.  It would also mean routing from the console back to the stern through the rigging tube, then back up to the bow.  That's at least 25 feet of wire and I would need heavier gauge and more resistance.  As opposed to the 5 feet I would need if mounted in a wedge on the bow.

I have the same trolling motor, the RT 74 24v. Minn Kota states, "For best results, use a deep cycle, marine battery with at least a 110 ampere hour rating."  Be that as it may, I use 2 interstate marine deep cycle 12v SRM-24 (690 MCA) for trolling motor and all other electronics with zero issues.  I knew minn kota suggests a higher amp hour battery, but I also know the performance of this trolling motor with two 24 class batteries.  I also have a 17' boat, like yours.  Believe me, a 24v trolling motor will make your boat scoot.  So even though I am one of those people who like to follow the manufacturers recommendations, in this case I did not and I'm more than satisfied with the result.  Your call.  But definitely take a look at your house battery to confirm its class.  Remember, you don't need to have the largest class battery, it's only recommended.  Big difference.

Second, while I don't own a trolling motor I personally would want a dedicated power source for it. While I would guess under the right conditions, you could get home on the trolling motor should your starting battery die

Still, running the trolling motor all you want without fear of possible adverse effect on other electrical systems is a "peace of mind" thing to my way of thinking. Since we have a few members who are running trolling motors, I'd be curious how many are using their "house" battery bank to power it. Hopefully, they will chime in.

Depends on how many and what electronics are tied into the two 12v batteries being used for trolling motor.  If you're running electronics that require a moderate amp load, such as stereo's, large screen navigation/gps screen, multiple bilge/baitwell pumps, aesthetic LED lighting....then yeah I would suggest 2 separate batteries for the trolling motor.  Me, in my boat I have a bow light, stern light, LED deck lights (2), and a baitwell pump.  These individually pull very very few amps, and all together they don't pull enough amps to cause concern.  Primarily because rarely are all of these on at the same time. 

And fortunately I have made it back to the boat ramp using trolling motor after engine failure, which was up wind and up tide 1 mile away.  Had the engine failure been due to the cranking battery I could have used either one of my accessory batteries to crank.

[CTsalt12]

Thanks Jason.  I have my bow, stern, courtesy lights, stereo, bilge pump, and a 7 inch GPS/FF. I will reconsider running through the console.  I've had my boat for 6 years now and have only replaced a battery once, so it seems I'm not putting much load on them. 

It sure would be  nice to return one of these pricey batteries, and have all of them tucked neatly into my console.  I will also say that a lot of guys (most?) with our size boats seem to have batteries in the console. 

I guess what scares me about the console idea is just running the wires through my jam packed rigging tube, and then back up through the gunnels.  I have bad memories of doing that when I replaced my steering cable, and replacing fuel lines...

 

[boatnamesue]

Thanks Jason.  I have my bow, stern, courtesy lights, stereo, bilge pump, and a 7 inch GPS/FF. I will reconsider running through the console.  I've had my boat for 6 years now and have only replaced a battery once, so it seems I'm not putting much load on them. 

It sure would be  nice to return one of these pricey batteries, and have all of them tucked neatly into my console.  I will also say that a lot of guys (most?) with our size boats seem to have batteries in the console. 

I guess what scares me about the console idea is just running the wires through my jam packed rigging tube, and then back up through the gunnels.  I have bad memories of doing that when I replaced my steering cable, and replacing fuel lines...

I've got all 3 batteries side by side directly under the seat area of console.  Pictured below, the view of 3rd battery far right is blocked by oil reserve tank.  Depending on the size of your console will obviously determine how many batteries can fit.  The 2nd pic shows you my console.  Just to give you an idea of the total width of the 3 batteries....all 3 side by side fit within the edges of the fuel tank hatch, with about 2" of space to spare on either side.

[CTsalt12]

Thanks Jason.  I have my bow, stern, courtesy lights, stereo, bilge pump, and a 7 inch GPS/FF. I will reconsider running through the console.  I've had my boat for 6 years now and have only replaced a battery once, so it seems I'm not putting much load on them. 

It sure would be  nice to return one of these pricey batteries, and have all of them tucked neatly into my console.  I will also say that a lot of guys (most?) with our size boats seem to have batteries in the console. 

I guess what scares me about the console idea is just running the wires through my jam packed rigging tube, and then back up through the gunnels.  I have bad memories of doing that when I replaced my steering cable, and replacing fuel lines...

I've got all 3 batteries side by side directly under the seat area of console.  Pictured below, the view of 3rd battery far right is blocked by oil reserve tank.  Depending on the size of your console will obviously determine how many batteries can fit.  The 2nd pic shows you my console.  Just to give you an idea of the total width of the 3 batteries....all 3 side by side fit within the edges of the fuel tank hatch, with about 2" of space to spare on either side.

Nice boat and nice organization of the wires under your console.  I don't have quite as much space because my seat forward of console has a livewell / storage hatch. I could still fit a 3rd battery in there no problem though..

[boatnamesue]

Thanks bud.  I just replaced the fuel tank, so whn I had the console out I was able to organize all the wiring.  It was a disaster of wire disorder under there.   I'd prefer having your console though with the baitwell in middle of boat.  My only option was a above deck baitwell, port stern. 

[CTsalt12]

So I went out fishing yesterday with 2 batteries in the front hatch to test how it rides.  We had a nice 1-2 ft chop last night in the long island sound, wind honking around 15 mph.  There's definitely a noticeable difference in the ride.  I was really pleased with the difference when up on plane.  I feel the boat didn't bounce around as much or catch a gust of wind when at the crest of waves, and pushed through the chop a little better.

The downside is that when idling the boat sort of 'plows' through the water and rides lower in front.  Also when drifting in the 2 footers with wind against current, the bow had a tendency to bounce a lot close to the water level than before.  Came really close to having water come onto the bow deck, but it didn't.  I was alone in the boat though.

There's clearly some pros and cons.  Weight distribution-wise, the best position probably is the center of the boat in the console.  Installation-wise, that may be the biggest PITA, and I may not be able to return the 10 gauge wire I bought.  I Have to make up my mind on where I'm going to put these..  May do a ride tonight with batteries jammed in the console to test.  Really I need to get moving on the installation as the best fishing season around here is a week or 2 away.

[boatnamesue]

So I went out fishing yesterday with 2 batteries in the front hatch to test how it rides.  We had a nice 1-2 ft chop last night in the long island sound, wind honking around 15 mph.  There's definitely a noticeable difference in the ride.  I was really pleased with the difference when up on plane.  I feel the boat didn't bounce around as much or catch a gust of wind when at the crest of waves, and pushed through the chop a little better.

The downside is that when idling the boat sort of 'plows' through the water and rides lower in front.  Also when drifting in the 2 footers with wind against current, the bow had a tendency to bounce a lot close to the water level than before.  Came really close to having water come onto the bow deck, but it didn't.  I was alone in the boat though.

There's clearly some pros and cons.  Weight distribution-wise, the best position probably is the center of the boat in the console.  Installation-wise, that may be the biggest PITA, and I may not be able to return the 10 gauge wire I bought.  I Have to make up my mind on where I'm going to put these..  May do a ride tonight with batteries jammed in the console to test.  Really I need to get moving on the installation as the best fishing season around here is a week or 2 away.

Kinda surprised to hear you almost took water over the bow bc of the extra battery weight.  These hulls have a high bow rise from water.  Guessing they both weigh round 80lbs.  If your trolling motor is not mounted then add another 30-40lbs depending on the model.  If you keep an anchor in the bow hatch you could put it in a plastic laundry basket at the stern, that will reduce bow weight. 

Depending on where you bought the 10g wire, good chance they'll allow you to exchange for different size.  Its not like they cant resell the length you already bought.  Definitely won't hurt to ask. 

[CTsalt12]

I was surprised too Jason...  However I was running on a 6 gal remote tank last week because I didn't have time to take it to fill up at the gas dock before 5 o'clock.  With 20 gallons in my below deck tank this weekend it was a different story.  I am also going to stick my anchor in a round rubber basket type thing in the stern like you mentioned.

So, I decided to put them in the bow.  I cut the railing yesterday, and built a little "T" shaped brace for the 2 batteries to sit flat in the bow hatch.  Pic attached for reference.  The picture in the boat was before I built the "T", and I was just sizing up the length of 2x4 needed.  You'll see I added two lips in the picture when I built it.  Then I wired the batteries with heat shrink ring connectors and butt connectors.  I am not using battery boxes or a circuit breaker at this time, just battery terminal covers. Bad idea?  The engine worked like a charm, man this thing is going to be sweet and I'm going to catch a lot of fish with it.  No more cranking the loud 2 smoke to adjust spots or re-drift or hold position.

I think the T Brace will actually be pretty stabile, and the heavy @#*$ batteries and gravity will hold it all in place.  It will also help that I'll have 2 boat covers jammed in the hatch when underway.  I'm most concerned about the batteries and t bar flipping back toward the stern, so I may drill the t bar brace to the wood glassed in between the front hatch and my other bow hatch.  I'll attach pictures to show what I mean when I'm down there again.

[boatnamesue]

I would definitely secure the T bar inside the well.  And secure down the batteries to the T bar with straps.  I also suggest weatherproofing the hatch to seal out water.