For those of you who have their graphs hardwired to the cranking battery, when your battery isn't charging or the engine isn't running, does the power connection drain the battery while the boat sits? If so, how long before the battery is drained enough to not be able to turn over a HPDI engine? Group 27 interstate battery, fairly new. Thanks!

Mine are hardwired but I'm a little confused. Are you talking about after you pull it off the lake and remove the graphs? I pulled an older group 24 out of my boat, which really wasn't bad just old, and bought a group 27 Interstate cranking battery. My boat has been parked 2 weeks and the battery must have been pretty well drained because it took it much longer to charge than my 2 group 27 deep cycle batteries I bought from Sam's about a year ago. On the lake with and HDS-8 at the console and HDS-7 at the bow the battery drains quicker than my old one. I'm a little disappointed with the Interstate battery. I wouldn't think there wouldn't be a drain from the power cord while it is parked with the graphs removed and the accessory and power switches off.

Wellllllll, alrighty then. Totally not how I had read it so here's an edit.

I always turn my graphs to stand by. Seems to help. Running you livewell pumps on time also helps.

Sorry for the confusion, I meant in your garage, storage facility, etc. Here is my scenario, 5 months ago I bought an interstate 27 cranking battery. I leave my boat in a storage facility, but on a charger. When I fish, I leave my boat at my house overnight the night prior, at most for 12 hours and it's off the charger. I've never had an issue and wouldn't think there would be an issue, but the last two trips when I launch, my graph tells me I'm at 12.7 volts, but when I go to turn the engine over it drops to 8 volts and won't turn the motor over. I've had to jump the battery, but when I do and warm the engine up, it runs all day with graphs on/live-wells running etc. and it always turns over. I called interstate about the issue and they told me to bring the battery in. I charged the battery full, got the boat, hooked it up to ears and tried to turn the engine over and it again dropped to 8 volts. I brought the battery to interstate, they ran a test, and then a load test and said the battery seemed fine. They're doing more testing in the next day with it, and going to tell me the results tomorrow.

When you engage a starter that won't turn over with the attached battery, you've started a downward spiral. A stopped starter motor is essentially like a dead short. That effective dead short is going to drag the voltage down in an instant because the battery doesn't have enough energy to deliver to spin the starter with that compression load on it.

They may say the battery meets spec, but I'd say it's a crappy one.

There are some electronics modules that do draw a small amount of power. I believe that I saw at least one version of the LSS boxes with a spec in the milliamps, but that would not kill your battery overnight.

Sorry but ur first problem is a interstate battery

Please expand on your observation.

Be aware if you have an external GPS networked and that network draws power directly from the boats battery, the GPS receiver will remain on all the time and drawing power. I believe its recommend to install a switch between the battery and NMEA-2000 buss.

I'm hoping it's just a bad battery, and a replacement will fix the issue. I run a HB 1199 and HB 999, so the LSS isn't something I'd deal with. Wish I would have gone with the group 31 agm in the first place, but I was in a tight squeeze and the previous battery that came with the boat was an interstate so I picked the same one up because it was in stock.

I run interstates thru out all the boats I have owned. Only had an issue once with my cranking battery dying at the end of 4 days straight, the last two running everything in the boat, live wells, electronics and lights. At the end of the second tournament day main would barely crank and graphs. 998 and 1199, would not stay on. With this being said took the battery in and had it load tested, it tested good. They then did cell test and I had one bad cell. Make sure and check each cell. Never had another issue with interstate.

Don't know if you have them but if you have power poles you need to get a cutoff switch so the bluetooth isn't searching for signal which over time could run down battery.

That is very true. But, he seems to indicate that while the boat is in storage, the charger is plugged in 24/7. The PP load won't hurt anything while that charger is active. He brings it home Friday evening to fish on Saturday morning. The PP bluetooth should lower it's power consumption after no activity, so I do not think that small drain overnight is a culprit for killing his battery so readily.

A test he has not mentioned is whether the cells have been checked with a good hydrometer (not a cheapie pencil-size tube version). A bad cell will typically show itself via such a test.

Check and clean every connection too. Not that this IS the problem, but it surely could be.

Just curious, plugging it up at the house isn't an option?