Actually I think you can ( i have by accident), but the point is if you leave something on or one alternator goes bad you will have TWO DEAD BATTERIES, and not just one, thus be dead in the water, and defeat the purpose of having two batteries.

Hello, I noticed your conversation and wanted to offer some assistance. We do make Group 27 BlueTops and YellowTops. The “R” in Group battery sizes indicates a reverse post configuration and we do not currently offer Group 27 batteries in that configuration. If your batteries are run in parallel, they need to be identical in size, type and age. If batteries are properly isolated from each other, different sizes and types can be used.

Interstate does not own Optima, Johnson Controls does. We still make all of our own batteries in our own facility. They are the only batteries made there and we never re-brand or re-spec them for any retailers. fountain 47 sc, I have never heard of Optima offering any type of lifetime warranty. Is it possible this was an offer made by a retailer? If you still have the paperwork, I’d love to see a copy of it.

The bottom line for any battery is making sure voltage doesn’t drop below 12.4 volts. If it does drop below that level, it’s important to make sure the battery is recharged as soon as possible. Batteries that are left in a partially-discharged state begin to sulfate, which diminishes performance and longevity. That’s why battery tenders or maintainers are excellent investments, especially if you are running multiple batteries. If you have any other battery-related questions, I’ll do my best to answer them.

Jim McIlvaine
eCare Manager, OPTIMA Batteries, Inc.
www.facebook.com/optimabatteries

I'll take you up on your offer!

Twin engine boat, 525 EFI's, Group 27's now, not into the monster stereo deal, not a lot of electronics, just want cranking amps and use cabin lighting on a limited basis. Last boat I decided to go with a pair of matched dual purpose batteries, worked out well and now thinking I will do the same again.

Sound choice? Is there an Optima that will fit the bill for me?

make sure the batteries are fully charged when you put it into storage.

Are both Optima and Interstate batteries made by Johnson Controls?
The interstate Website has Optima Batteries pictured and they sell them. I thought they had acquired Optima but it makes sense that a giant like Johnson Controls owns/manufactures both. Do you make Interstate Batteries in your facility?

Batteries from Johnson Controls in all of our size ranges come from Mexico as well as others.

East Penn is one of the last companies I can think of that still makes batteries in the U.S. (for our size range gr27 etc..)

Single engine, you should be fine running with the switch on both. Some people claim (no idea if its true or not) that running twin engines with both batteries on "both" can cause cross charging and damage the electronics.

Thanks for the info everyone I appreciate it!

Hi RaggedEdge, the first thing you should do is check the manufacturer’s specifications for your boat’s engines, as you don’t want to select batteries that do not provide the necessary cranking amps for your application. If Group 27s meet that requirement and they have worked well in the past, we do offer BlueTops and YellowTops in that size. If you’d like more cranking power and reserve capacity and have the space for it, you can move up to a larger Group 31 battery, which we also offer in a BlueTop.

mcprodesign’s advice about making sure batteries are fully-charged when put into storage is very good. I’d also suggest a maintenance charger for storage, to keep them at or above 12.4 volts.

fountain 47 sc, Johnson Controls does manufacture batteries for Interstate and JCI is Optima’s parent company. Interstate does distribute and sell Optima batteries, but the only batteries made in our facility are Optimas. You can view a video of our facility here- http://www.optimabatteries.com/contact_us/mexico_video/

If anyone has any other battery-related questions, please don’t hesitate to ask.

Jim McIlvaine
eCare Manager, OPTIMA Batteries, Inc.
www.facebook.com/optimabatteries

I have a simple question I have a set of Interstate NG-27's do you know if the Optima's would be a direct replacement size and post location ect....????