Changing Battery Location on my tomcat 255

C

ChapaRRal Cock

New member
I am a Happy new owner of a 2009 tomcat. The Layout and Install of some of the Niceties has me scratching my head. Admittedly this is my first boat of this caliber. My previous being an 86 trophy. I spent this last weekend in Westport salmon and bottom fishing. Was EXTREMELY happy with fuel consumption and handling. Not so happy with my scuppers living underwater and no bait well. This particular boat is outfitted with 2 lifeline GPL 2271 start batteries at 62lbs each and 4 GPL6CT 6 volt house batteries at 90 lbs each :shock: 484lbs of batteries in the back of the boat. My question is this going through albums of different tomcat owners I noticed rogerbum in his album seadna accessed a area under the captains helm.. I am thinking of relocating my batteries to this location.. I would REALLY appreciate any and all thoughts..
 
Well you can save some weight at the loss of redundancy and house capacity just by reducing the number of batteries.

You can rewire so that one start battery handles both motors. Also 4 GC batteries is a bit heavy unless you have heavy loads while the engine insn't running. You can probably do with just two.

That change will drop about 240 lbs. You might want to see about how you could start your motor with the house batteries in a pinch given no start redundancy.

David
 
James;

All the TC255 have this problem. Move the batteries into the house which requires sealed batteries.
Under the helm seat poses the problem of access. The water heater is there and difficult to access when needed. Another issue with mounting at helm seat is weight distribution The freshwater tank is on the starboard side as well as the head. any addition of weight should be port if at all possible. My start batteries are in the refrigerator compartment. Easy to access and closer to battery charger. My house batteries are in the hanging locker also closer to charger and inverter. Some storage space is lost but you can build a box to cover the house batteries just leave room for venting.

Good luck your scuppers are still going to be low but, this helps a little.

Gene
 
I don't recall seeing a Tomcat without a baitwell. All the ones I've seen, including mine, have the baitwell under the bench.

I have two starter batteries and one house battery at the stern and haven't had any issues with the scuppers unless I have four divers with eight scuba tanks at the stern at the same time.
 
I was under the impression that the water tank was under the fridge on the port side? As it is set up right now both batteries feed both motors I pick dependent upon my selector switch. I was thinking about cutting a hole in the floor and putting the batteries in the sponson? I think that is what its called.
once again appreciate all the nautical and practical experience.
 
I don't recall seeing a Tomcat without a baitwell. All the ones I've seen, including mine, have the baitwell under the bench..

Mine was removed and that is where my plethora of batteries reside.
My hot water heater is under the sleeping berth port side and the expansion tank is mounted in the hanging locker.
 
They might have changed the location of the water tank. To be sure, there is access under the sink, open the hatch and shine light forward you will see the tank and lines running to demand pump if not it has changed.
The design of my 2007 model lists starboard when all tanks are full. Much less since I repositioned all batteries to the port side.

My water heater is located in the cabinet under the helm seat with no expansion tank in system. The only expansion tank on my 2007 is the one for the hydronic heating system that I installed.

Gene
 
The water tank can be under either the port or starboard side. I had ordered with two water tanks--and during the build they informed me they would not put it under the port side-(I suspect that they had already put in the dinette furniture and forgot to flag the boat with a special order. I finally got the extra tank--but never installed it. It should still be with the boat...

I put AGM batteries under the port side since my water tank was under Starboard.

But, I would not put the battery down in the hulls.

My boat (2007) was ordered without the bait well option (under the aft bench seat--not sure if the factory still has the molds for that bait well--it they do, you could order it, and drop it in place (with fiberglass). But the 30 gallons of water would weigh 180#...

AGM batteries can be put on their sides or ends--but not upside down. You want to have access to the terminals for maintenance.

I probably would keep two group 24 starting batteries aft, and get rid of the golf carts--(Although you can get AGM golf carts), and go with two group 31 house batteries for the "house". I had a second set of 2 group 31's for the inverter, running microwave--plus I had both a chest freezer / refrigerator in the main cabin (no small front opening refrigerator) and a chest freezer / refrigerator in the cockpit--so had a bit more house demand than the average boat.
 
Honestly, Bob, you were the one I was hoping would chime in. I have gone through your albums and realized you have done some electrical upgrading.
Why would you not put the batteries in the Hulls? I was going to build a platform and epoxy it to the hull to raise the batteries up and to be able to secure them. rogerbum on SEADNA cut an access hatch thru the floor in front of the captains helm that is where I was going to access and it would offset the water weight from my freshwater tank.
 
ChapaRRal Cock":2drr6yth said:
Honestly, Bob, you were the one I was hoping would chime in. I have gone through your albums and realized you have done some electrical upgrading.
Why would you not put the batteries in the Hulls? I was going to build a platform and epoxy it to the hull to raise the batteries up and to be able to secure them. rogerbum on SEADNA cut an access hatch thru the floor in front of the captains helm that is where I was going to access and it would offset the water weight from my freshwater tank.
Click to expand...

My apology, I missinterpreted in the your first post, that you were considering forward under helm foot rest area. I was going on your post:
. I was thinking about cutting a hole in the floor and putting the batteries in the sponson? I think that is what its called.
Click to expand...
If you want to put the Lifeline 300 amp hour AGM batteries, up forward, --say under the helm area--that would be fine, if built up on a platform. The reason I suggested against it, was if they were to be put aft, there is an issue with getting the bilge completely dry with the Tom Cat. Not only water itself, but the high humidity in the hulls, tend to accelerate corrosion. If you are willing to inspect the batteries regularly, that would work. Unfortunately the Tom Cat tends to have a lot of weight in the stern--and that also affects performance. You don't want to get weight too far forward. These four batteries are 360#. How this affects the trim of your boat will depend on where other heavy items are located. In my boat the water tank was on Starboard, and I put the batteries amidships back in the cabinets.

Not sure how you were going to epoxy a platform to the hull, but here is what I did for the Lithium ion batteries I put under the aft end of the port side of V berth.
I cut out the plywood, and epoxied "cleats" around the edge which would not be against the hull or bulkhead. I then coated the entire platform with epoxy. Before putting in the boat--any "legs" going to the hull were cut from cardboard patterns I had made. They were also attached with epoxy to the plywood platform. Any area which would be in contact with the hull, and area where I would be putting 3" fiberglass tape, was cleaned of any amine blush and sanded lightly. I sanded the hull, and any painted wooden bulkhead, to give a good surface to epoxy to. I overlapped the glass tape equally over the platform, and the hull surface. I made a small fillet with thickened epoxy to give some radius and avoid a sharp transition at the joint. of the platform and hull.

Incidentally those Lifeline AGM are not the standard Golf Cart--they are over twice as expensive--and worth keeping. (Again, I didn't look up the specific battery, my error). These are 50% more capacity than the standard (about 205 amp hours) GG. Also weight is about 30# more. 30 gallons of water is going to weight about 180#. So be careful with trim...
 
I appreciate the follow-up. Would you consider dropping to a single start battery? I have the ability to hit a switch and combine house and start batteries to start. Honestly not sure where the batteries are going. I just know I need to move them forward. If I can keep them all one side will keep installing much simpler. The nice thing is I have wiring layout for the complete boat. If you have any other thoughts please don't hesitate to say something. Thanks for the insights and help. James
 
I have always had two start batteries, when I had dual engines--inboards or outboards. On my long distance motor sailors, I had two start batteries, for the single Diesel engine. The reason being, I had by house batteries some distance from the engine--and I always wanted reliable start--alternated use each day running. Although golf carts are not designed as starting batteries--the ones you own should start most outboards in the size used on the Tom. Cat.

I don't know how the boat is wired--or why they put that high a battery capacity aboard--300 amp hours usable, is a lot of power. If you move them forward, you will want to have adequate cable for charging (I don't know if the standard cable to the console has been upgraded or not.

We also don't know what engines you have= what the charging capacity is. Does each engine have a split charging circuit (second circuit), do you have ACR's (Automatic Charge Relay). Also the house battery charger should be matched to the size of the battery bank. A 10/5/5 guest is going to be way under performing for that battery bank. Is there an inverter/charger--if so what size?
 
I have dual honda 150's counter-rotating.

The original owner of the boat was an electrical engineer and specified changes he wanted along with new wiring schematics which I have. Looking at the owners manuals I have a
mastervolt IVO Smart Battery charger 12/50-3
Along with a mastervolt Inverter12/200 with the Mastervolt masterlink inverter charger control. If I move the batteries forward I can actually use the same cable just run forward instead of aft. Yes I have ACR's. I have a spool of 2/0 Marine wire red and black laying around I was going to use if needed. I figure bigger is better. I am not going to overheat wires
 
If you go with a single start battery, you probably will have to do a bit of wiring so that one battery can start both engines. With two starting batteries, they typically start and charge one engine each.

With the switch you describe where your house can start the engines you won't lose much redundancy with a single start battery. As noted above a pair of GCs can start most outboards. Try it.

Then reduce your house batteries to a pair of GCs or G31s. But you need to evaluate how much load you have without the engines running. The PO installed those 4 GCs for a reason, but maybe he wanted the ability to hang out at anchor for several days at a time and you don't need that.

David
 
It is obvious that the PO put in first class gear, and did his research. Are your sure about the model number of the Master Volt inverter? I don't find that listed in the current catalog. My best guess is that is a 12 volt DC, 2000 watt/120 Volts AC--not 200 watt pure sine wave inverter. That makes a lot more sense. Many of these also come with an 80 to 100 amp battery charger as part of the Inverter/charger. (For example I use a Vectron 2000 watt PSW inverter, with an 85 amp 12 volt charger.). It is very possible that he installed just the inverter.

Now consider that at full 2000 watt output the inverter is pulling a little over 200 amps an hour out of your battery bank--and that is why he has the 4 golf carts. Probably your Honda's alternators each put out in the 50 amp 12 volt category, at max output. There is some utilization for the operation of engine, and boat's systems, such as electronics, lights, pumps etc. Figure that max charge is going to be in the 30 to 40 amp range. (I have limited my Honda 150's charging to my Li ion batteries to 30 amps max, thru a "Battery to battery charger"..

The MasterLink Charger / inverter controller, should show you amp hours consumed by the battery and state of charge of the battery bank. It also measures voltage (only) of the start battery (which is all you need).

So the PO had a reason for the big golf cart bank. Is it necessary? No, the two golf charts would be fine. But you have a rather expensive setup and it is logical to make full use of it.

Yes, you can use the existing cable--but we don't know the size--if it is 2/0, that is way overkill (it would be good for 100 amps/12 V DC. For 50 amps, you want 2 gauge wire (figuring 40 foot and 50 amps).

The next question is where does your windlass draw its power from? You want to have the outboard running, and charging that battery. I power mine off the engine start battery--but others use the house battery. So you want to check out that circuit. (Great that the PO provided a circuit diagram--I sure wish I had one, I periodically find unlabeled wires--and don 't know if they are to code or where they originate and terminate.). This why I label wires when I pull new ones, at Origen and termination. For example today, I found two #10 green, with black stripe, and one black wire, in a bundle--orignional factory wiring, which terminates under the hanging locker--with about 10' of wire in a loom. Green with stripe, is trim / tilt; up / down, but I have those functions in another set of wires...

I would keep the two engine start batteries--Are you sure about the model number--I cannot find it in the Lifeline catalog--but I may be missing something--the weight of 62 lbs suggests it is a group 27 battery. (Lifeline group 24's tend to be in the mid to low 50# category. In any case these are high end batteries, and well worth keeping!!!

If you were to go down to one engine start, then I would run the 2/0 cable to the house bank from the engine combine switch.
 
Just to throw in a data marker....this boat was originally "Knoty Lady" and the operator was somewhat active on this site. I recall seeing discussions of the electrics when new. And this boat does, indeed have the fresh water tank on the port side ahead of the refrigerator.

Randall
 
I agree on two start batteries for two engines
(per Honda Rep).

Also minimize distance from start batterys to engines;
bad for weight distribution often but good for engines
and batteries.

Aye.
 
Amazing Info, I love all of the participation. I do plan on keeping and utilizing all existing batteries. I went through and labeled all wires and confirmed via the wiring diagram. I have a new layout started. I will be shortening so many wires! The only wire that I will be adding will be for the motors, and I will go with a large 2/0 ground and positive cable to feed the motors. I am excited to see how this turns out. I will contact the moderator to get permissions so that I can post pictures.
 
Foggy":3chg6b56 said:
...
Also minimize distance from start batterys to engines;
bad for weight distribution often but good for engines
and batteries.
Aye.
Click to expand...
Yes, but... the engines have no knowledge of where the batteries are. They just want to have sufficient voltage and that depends on resistance between batteries and engine, and that is a factor of both distance and wire size. The OP can move his batteries farther away and with big enough wire can actually have less resistance and lower voltage drop than before.
 
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