battery switch

[nob]

hi all, i'm still in the process of finishing my sr4 and have come to the point where i fit a battery box and isolator, question is what rating isolator do i need for a merc 50 2 stroke and where would the best place to put it be? i was thinking of fixing it to the transom but i'm guessing it'll get wet unless you can get waterproof ones? any ideas?

[ShinyShoe]

You can get waterproof ones, but they aren't that good. Most people put them inside the console, but still use a waterproof one.

But that means the battery will probably be in the console too...

Rating - dunno - but the battery size presumably affects it too...

[pow2gran]

Originally Posted by nob

hi all, i'm still in the process of finishing my sr4 and have come to the point where i fit a battery box and isolator, question is what rating isolator do i need for a merc 50 2 stroke and where would the best place to put it be? i was thinking of fixing it to the transom but i'm guessing it'll get wet unless you can get waterproof ones? any ideas?

I thought about a battery switch but have fitted stainless wing nuts to the battery terminals. I disconnect the battery quite easily and can take the battery out easily. Cost 10p!

[spartacus]

I put mine on the console as I'd forget it if it was fitted inside. Put a bead of Sikaflex around the circumference of the hole prior to fitting. Regards the isolator, then any Blue Sea product should be top of your list. I've been out in some fairly rough weather, jet-wash the boat thoroughly after ever trip and it's been dry inside the console as a bone from day one.

m-Series (Mini) Battery Switches - PN - Blue Sea Systems

[gotchiguy]

Originally Posted by pow2gran

wing nuts to the battery terminals.!

Not good! Specifically states in most engine manuals never to use wing nuts on battery terminals!

[9D280]

As a general rule they are rubbish!

Donlt know how much you have been around dinghies, but mine is fitted in a "hatch bucket" - best way of describing that is if you go to the Laser website, some boats have an access hatch (they come in various sizes) beside the centreboard slot which are waterproof round hatches big enoug hto gey your arm / hand through. Most makes have a "bucket" that can be dropped into the hole (it engages o nthe flange) and then the hatch closed on top of it - keeping it & iot;s contents nice & dry. That should prolong the life of the switch & give easy access to it. (Pics on Laser dinghy websites)

Other thing is make up a short jump lead - that when when (and I do mean when) it dies, you can jump the terminals to carry on & get home. Probably more important for your VHF, if you have one.


Having said that, if you don't have electric stuff (plotter / radio etc) then worst case if the battery or switch dies, you walk to the transom & pull the emergency start rope. A 2- stroke will not need the battery to keep it alive (unless it's one of these new fangled DI types? - I assume yours is an "oldschool" 2- stroke)

[Erin]

Originally Posted by gotchiguy

Not good! Specifically states in most engine manuals never to use wing nuts on battery terminals!

Why's that then? My leisure battery came with wing nuts on the terminals.

[jyasaki]

Couple of reasons: Wing nuts are generally only hand-tightened, which doesn't torque them enough to stay tight. They are also prone to impact loosening.

If you use tools to tighten them, you eliminate half the problem (though you'll also need tools to loosen them again, which sort of defeats their purpose anyway.)

jky

[nob]

i knew it, its all got complicated . if i've got no electrics apart from the outboard starter, do i need an isolator? please dont shout i'm a newbie

[9D280]

Chill. everyone is a noob at some point!

Main isolator. Do you need it? Personally I'd say yes. I also know boats without.

Possible scenarios: ignition switch or solenoid jam "on"... Battery cable gets chaffed through years of use & suddenly shorts... You eventually succumb to electrical toys, and need to "kill the boat" for storage in order not to flatten the battery... Servicing / mid channel repair... You get the idea.

The biggest failing of these switches is usually water ingress. Keep it dry & it should last gfor a reasonable time. Or buy a f***ing expensive one & it will survive longer.

Yes, you could just disconnect the battery, but you can guarantee that you'll need to do it in a lumpy sea, dropping your spanner which wil lget washed down the deck having just filled the console with salt water as another wave breaks over the bow.....

Pessimist? Nah, jsut an advovcate of a law written by Mr Sod!


Would a "high level" look at electrics be useful?

[nob]

cheers 9d280, you've just confirmed the niggling thoughts in the back of me 'ead!, it does make total sense so i'm of to get a bluewater jobbie and a ton of sikaflex!! many thanks all

[nob]

doh not bluewater dumbass! blue sea systems!