Cranking battery problems

[jland6003]

2018 200 Merc

2 HDS LIVE w/ Point 1

Battery- Interstate Group 27 XD

My cranking battery keeps getting killed. Both HDS are wired to the cranking battery. I always take off the HDS and key. Power switch was off. I forgot to turn the breaker off. My boat sat for two weeks, and the battery was dead. I know it was my fault with the breaker. This is the second time in 6 months this has happened. First time my boat sat again for two weeks and killed the battery. The place I take it to, said they couldn’t find a problem. This started happening after they wired the HDS and Point1 . Both times no units were hooked up, key was out and main power switch was off. Any Idea? Ball park of a problem? The battery has 185 reserve. Just looking for answers. I’m not a wizard with mechanics, just hoping to bring an idea to their attention.

thanks

[wmitch2]

If you forgot to turn the switch to the OFF position it will drain the battery because there is some draw even tho the key is off. You can test which one is doing it by disconnecting the NEG wires from the battery, then take one wire and connect the Clip from a Test Light to it, then touch the probe end to the NEG battery post. If it lights, there's a draw in that circuit. To find what is causing the draw, you'll have to go to your fuse box and pull each fuse one by one until the test light goes out. Then see on the diagram what that fuse is for. IF none go out after you check all the fuses in the fuse box, then check all your IN-LINE fuses until you find the one that goes out !! You'll have to do this for EACH wire that connects to that battery. Remember, the BIG wire goes to the MOTOR. So you can eliminate that wire from the test. I turn my switches off as I'm drying the Boat off when I open the Auto Bilge Plug which is in the bilge area, and switch the Live Well selector to EMPTY all as a matter of Routine. I'ts hard to say your Gp27 Battery is too small since the problem seems to be YOU, LOL !! But, when you need a new Battery, I'd recommend going to a Grp 31. As a side note, if your Interstate is a wet cell, make sure the water is always full.

[jland6003]

Even with a 31 I still would kill it when it’s my fault. Didn’t think 2 weeks would kill a brand new battery. Will a 31 make the units look more clear? I pull 11.6v on the trolling motor with the motor off. It’s a tight fit in the champion. I had to buy a smaller oil tank to go from a 24 to a 27.

[fishin couillon]

What is the nmea 2000 network hooked up to? It needs to be on a switch also to shut power off to it.

[jland6003]

I have 3 connection on the terminal with only 2 HDS. I would assume the NMEA is on the battery. I didn’t have this problem until I put the HDS AND POINT 1 on. I put a breaker on it after the first battery problem. I will have them double check when I get my 100hrs service. My boat needs to be re wired. It’s like Charlotte web under the dash and in the battery compartment.

[BoatNoobie]

automatic bilge pump? Is it wired directly to the battery? Been raining?

[CatFan]

If there is a load on the battery, your charger should never indicate the battery is charged.

[jland6003]

It doesn’t have automatic bilge that’s an upgrade in the future. It only sat for 12 days. I didn’t have her plugged up.