Rewire

I have a 24' Grady cc with twin Suzuki 140's that I am looking to completely rewire with dual house batteries and dual starter batteries. My questions:

(1) Can I connect the starter batteries (with battery switch, of course) to the breaker box (which is also connected to the house batteries) so that I can charge all 4 batteries when out to sea?

(2) Do I need any breakers (it would have to be high amperage) in series with the starter batteries or are they connected directly from the battery switch to the motor as seen under 'dual battery dual engine' here:
http://continuouswave.com/whaler/ref...alBattery.html

(3) Does anybody know what signals 2004 suzuki 140 4 strokes send? I.e. can I expect to find a temperature and oil pressure sender?

Regards,
TheGradyGuy

Re: Rewire

Your link is not properly formed. Perhaps you intended to point to

Classic Whaler: Boston Whaler: Reference: Dual Engine/Dual Battery

It is a common practice that the engine primary power conductors for engine starting are not protected by over-current devices in outboard engine installations.

It is impossible to describe clearly in a narrative manner how four batteries, two outboard engines, and a variety of loads and switches will be connected. You need to create a diagram of your proposed installation in order to allow others to understand your intentions.

A fantastic source of information about the primary power distribution for instances of multiple engines and multiple batteries is the Evinrude publication RIGGING AND PREDELIVERY E-TEC MANUAL. Although specific to the Evinrude E-TEC, the literature contains many excellent diagrams of battery installations and wiring which may be useful for you in planning your boat's power distribution and control. You can obtain the Evinrude literature online. The details of how to get the rigging guide are given in

Rigging and Installation Manual for new E-TECs - Owners Message Board

You can usually download the latest version from this link:

http://www.operatorsguides.brp.com/...sManuals_EJ/attach/Accessories/5008815 EN.pdf

In the literature linked above, see the section beginning around page 18. It shows many possible configurations.

Re: Rewire

Here is a thread from a few days ago on basically the same thing. Might give you some ideas.

It mostly depends on how much switch changing you want to do, or just turn things on and it takes care of itself and you don't have to worry about running your start batteries down when using house systems.

http://forums.iboats.com/electrical...-about-battery-setup-twin-crusier-601799.html

Re: Rewire

There are thousands of discussions on line in which people give advice on battery installation. It is hard to find the best advice among them all. Over time, I have found that outboard engine manufacturers give good advice. Also premium boat builders, like Grady White, will give good advice. You might consider contacting them for advice.

In the literature I mentioned above, see the diagram on page 19 with the legend "Two outboards, one primary battery each and two isolated accessory batteries. This is a clearly drawn wiring diagram which should give you a good idea of how to approach the wiring.

In the case of wiring, trying to describe it in a narrative is impossible. One good diagram should make things clear.

If you want to add a voltage sensitive relay or an automatic combiner relay, just follow the instructions that the manufacturer of those devices will provide you. The manufacturer will give you a wiring diagram and clear instructions on how to install their device.

Re: Rewire

jhebert said:

If you want to add a voltage sensitive relay or an automatic combiner relay, just follow the instructions that the manufacturer of those devices will provide you. The manufacturer will give you a wiring diagram and clear instructions on how to install their device.

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True, but that is only if one knows if such a thing even exists, what it's called, or where to find them.

The 1-2-Both-Off switches will work, you just need to constantly change them depending on what you are doing.

Re: Rewire

I am not familiar with the outboard engines made by Suzuki, but, if they are like many modern outboard engines, they may provide for dual alternator outputs which can charge two batteries at once and do it independently. This approach is much more versatile than adding all of these gadgets and gillhookies like automatic combiner relays or voltage sensitive relays.

The problem with these gadgets like automatic combiner relays is the extra components that are needed to install them--a mass of fuses, terminal posts, and other wiring devices--end up costing more than the automatic combiner relay.

I'd look closely at the Suzuki engines and accessories for them that might provide an isolated second battery charging output. That is really the best solution for charging two batteries from one outboard engine.

Re: Rewire

jhebert said:

The problem with these gadgets like automatic combiner relays is the extra components that are needed to install them--a mass of fuses, terminal posts, and other wiring devices--end up costing more than the automatic combiner relay.

Click to expand...

Whatever you say

Re: Rewire

Don S said:

Whatever you say

Click to expand...

It's not what I say: it is what the manufacturer says. If you read the instructions for the BLUE SEA SYSTEMS automatic combiner relay, the added components needed to install the device that are not supplied with it will cost more than the device itself. This is not my opinion, but the advice of the manufacturer and the cost of the components they require. You'll buy a $80 combiner relay and $85 of fuses, terminals, cables, and other necessary components to install it properly.

In addition, having an isolated auxiliary charging output from the outboard engine is a better method for maintaining two batteries whose loads you want to keep isolated. These combiner gadgets place all the loads in a common circuit when they combine them. The reason for having a separate house battery is to isolate the house loads from the engine starting loads. By combining them you undo the isolation that was the reason for having two system in the first place.

Isolated auxiliary charging outputs are available on Yamaha and Evinrude engines. If that option is available, it is a better method for charging two batteries whose loads you wish to remain isolated. The reason it is a better method: it costs less, reduces wiring complexity, and maintains battery isolation.

Feel free to roll your eyes some more.

Re: Rewire

I gave the man an option. That's all.

Your way is not the only way.

Re: Rewire

Don S said:

I gave the man an option. That's all.

Your way is not the only way.

Click to expand...

Using an auxiliary battery charging output from an outboard engine to maintain a second battery is not "my way." Using an auxiliary battery charging output is an option offered by outboard engine manufacturers.