Battery size?

[abruzzi]

What size battery normally fits in the battery compartment on a Mac 25 without causing problems? I'm guessing group 24, but I'm wondering what Macgregor originally specced for that area.

Thanks,

Geof

[yukonbob]

I've got two 34's in. A bit of a pain getting in and out, but its only once a year.

[TheJoe]

Probably almost definitely a group 24. You can find measurements online for the batteries. I'd put the largest that fits. If the slot is long you can go with a group 27 or 31.

[robbarnes1965]

I've got two 34's in. A bit of a pain getting in and out, but its only once a year.

I have a Mac M so I can't comment on size but I recommend jamming the biggest batteries you can and add these: http://www.amazon.com/Sunforce-50013-Mo ... B001D6GYLO
Don't pay that price however. There are other brands and on sale you can get them at $10. I used to wrestle with my batteries every fall and spring but now I keep the panels connected and hanging on the cover. You just need to visit the boat every once in a while to knock the snow off the the panels. My batteries stay fully charged and better maintained than if I had then at home.

[seahouse]

True story.

After 2 years, the battery on my high electrical-power-draw car (bought new) died (it has such a high power draw that the two radiator fan motors are hydraulic instead of electric to reduce that total draw).

The dealer installed a new battery under warrantee, and at the same time I installed one of these $10 at Canadian Tire solar panels permanently on the rear window ledge of the car. That battery is just coming up on 10 years now, and even in the present freezing weather it cranks over and starts quickly. (I do keep one of the boat’s batteries as back-up in the trunk over the winter just in case, though).

I noticed that the most recent literature on these panels tells you to not keep the panel connected to the vehicle while it is running. I’m not sure why – my setup has suffered damage to neither vehicle nor panel. Maybe transient voltages will overload and burn out the diodes(?)

The long life might have nothing to do with the presence of the panel, but one thing is for sure – the panel didn’t cause any damage.

- Brian.

[abruzzi]

Right now the boat parks right next to an outdoor outlet in front of my house, so my plan was to add a charger internal to the boat as well as one or two batteries, depending on what fits. I also expect to be re-doing the electrical system from scratch since what's there now is very minimal.

I'm thinking of using a 24v trolling motor for propulsion, so I think I should be able to put two batteries in series to get 24v, but tap off of just one two get 12v. Alternatively, I might do a heavy-duty switch to switch the batteries between parallel and series, rather than having to fit three batteries in there.

Since getting it I've been working on all the other parts of the boat, and since I hope to launch in a month or so, I need to sort out the electrics.

Geof

[robbarnes1965]

True story.

After 2 years, the battery on my high electrical-power-draw car (bought new) died (it has such a high power draw that the two radiator fan motors are hydraulic instead of electric to reduce that total draw).

The dealer installed a new battery under warrantee, and at the same time I installed one of these $10 at Canadian Tire solar panels permanently on the rear window ledge of the car. That battery is just coming up on 10 years now, and even in the present freezing weather it cranks over and starts quickly. (I do keep one of the boat’s batteries as back-up in the trunk over the winter just in case, though).

I noticed that the most recent literature on these panels tells you to not keep the panel connected to the vehicle while it is running. I’m not sure why – my setup has suffered damage to neither vehicle nor panel. Maybe transient voltages will overload and burn out the diodes(?)

The long life might have nothing to do with the presence of the panel, but one thing is for sure – the panel didn’t cause any damage.

- Brian.

Yeah, I got mine at Canadian tire too. They really do work. I went over 2 weeks ago to check out the boat and the engine easily raised and lowered electrically. The batteries are fully charged even in the -25c weather.

[Tomfoolery]

Not to anyone in particular, but one advantage of leaving them in that boat over the winter is that, if they're fully charged, they tend to self-discharge much slower in cold weather, and to not sulfate as much. I leave them in my boat, and trickle charge them once a month for a day. They've always stayed very close to a full charge, based on the charger indicators, and specific gravity. But then, I live where it gets cold in the winter, while the OP is in the south-west, I think.

[Crikey]

While the addition of a cheap, trickle charge solar panel is an eminently workable solution I'm not convinced it's the safest solution in 'the great white north' during winter. If something goes amiss and the battery(s) discharges during a severe freezing condition - it too will freeze, and burst!
Not a cheap fail for a Mac. (a riding lawnmower battery was my personal introduction to this scenario)

Far better to bring them inside.

Ross

[robbarnes1965]

While the addition of a cheap, trickle charge solar panel is an eminently workable solution I'm not convinced it's the safest solution in 'the great white north' during winter. If something goes amiss and the battery(s) discharges during a severe freezing condition - it too will freeze, and burst!
Not a cheap fail for a Mac. (a riding lawnmower battery was my personal introduction to this scenario)

Far better to bring them inside.

Ross

So far it's only happened to me with beer cans luckily

[Freedom77]

IT'S NOT THE SIZE OF THE BATTERY, IT'S HOW YOU USE IT!!

[Russ]

I've got two 34's in. A bit of a pain getting in and out, but its only once a year.

I have a Mac M so I can't comment on size but I recommend jamming the biggest batteries you can and add these: http://www.amazon.com/Sunforce-50013-Mo ... B001D6GYLO
Don't pay that price however. There are other brands and on sale you can get them at $10. I used to wrestle with my batteries every fall and spring but now I keep the panels connected and hanging on the cover. You just need to visit the boat every once in a while to knock the snow off the the panels. My batteries stay fully charged and better maintained than if I had then at home.

We typically get a week of -25F per winter. I've always been fearful of that kind of cold on my batts. Although my truck sits outside in the winter and seems to fair fine.

I may save my back and use one of these solar chargers. Actually I have one, but it's really cheap. Maybe too cheap as I once left it connected to a battery to find it dead after a couple of weeks. I blamed the solar charger and clouds.

[RobertB]

I keep my boat in the driveway with an extension cord to the boat. In the winter I keep the battery charger and a small heater on. Even though, I still add antifreeze to the water system in case of power failure. The heater is good in that the boat is comfortable to go out and work in it on the weekends.

[Knot Tied Down]

I keep my boat in the driveway with an extension cord to the boat. In the winter I keep the battery charger and a small heater on. Even though, I still add antifreeze to the water system in case of power failure. The heater is good in that the boat is comfortable to go out and work in it on the weekends.

Im so jealous! I brought out The propane heater today when worjing on the boat but it didn't help much. I wish I had the access to have a small heater going constantly.

[Crikey]

Robert, the fail in this case is the bursting of your hard-won water system if the particular blending of the choice of anti-freeze brand, that you made, is not sufficient to withstand an extreme overnight disruption of the heating system. For me, the fairly simple act of bringing the batteries inside, to keep charged, saves the worry of this kind of fail as well as the cost of the electricity used to provide the required heat.
Why, otherwise, would you pay to heat the interior of an already frozen boat other than to preserve any battery(ies) (or toilettries, for that matter) - escapes me! Considering many, like me, have the exterior of the hull frozen harder than carbonite during most of the year, why would there be logic in expenditure to save the carpet from freezing? We all know that the colder the electronics work, the better they get! Particularly the plastic parts...
To work, at a time of your choosing, really involves not much more than twenty minutes of pre-heat. Believe me I know - because I've almost never done it!

Coming back to the crux of this article; I'd say the more battery you have - the better.
Ross