2nd battery (frame) cuttoff switch 2001 7.3

[bonedoc]

I was curious if anyone has installed a disconnect switch at the frame rail secondary battery on the 7.3 van configuration. It seems it would be much easier to interrupt the power from a switch rather than dropping the battery box.
Also would like some input re: using a waterproof (marine) switch or boxing (Pelican case?) a switch up to attach to the frame to keep the weather out. Thank you for your input!

[daveb]

I used a covered Blue Sea terminal block mounted on a delrin block. Both starting batteries hit the block as does my separator circuit to the house batteries. The terminal block is mounted high enough to keep out of water, is fairly easy to access, and is rated for 300A IIRC. As far as a breaker, cold weather starts can pull some big amps. I'd think a high amp fuse block and fuse would be better to use than a breaker JMO,

[dhally]

Our aux batteries are connected under the van with a frame mounted circuit breaker. All open to the road environment... No problems so far, except it was dirty when changing batteries.

[daveb]

Sorry I misread your post and thought you were referring to a breaker between the starter and starting batteries. I have a high amp breaker on the side of my battery box on the frame that feeds my extreme air pump. No issues at all with it.

[bonedoc]

Hi Dave.......thanks for the reply. I had hoped to just use a simple disconnect inline on the positive cable. I get tired of dropping the box and dealing with the terminals. I might be simplifying this too much......not sure?

[Lilnuts2]

Bonedoc, I also have a 7.3. I'm strongly considering moving the underhood battery down next to the 2nd frame battery and installing one main disconnect that is accessible from a hatch made in the sidedoor footwell. I would also install remote therminals in there for jumping or charging if needed, but mostly as a theft deterrent and to also centralize the power source.

[bonedoc]

That sounds like a great idea! Let us know how it turns out. Thank you, Steve

[daveb]

Originally Posted by bonedoc

Hi Dave.......thanks for the reply. I had hoped to just use a simple disconnect inline on the positive cable. I get tired of dropping the box and dealing with the terminals. I might be simplifying this too much......not sure?

A few things to think about are the high amps a diesel starter can pull. I'd rather not have a protection device between the two starting batteries and would prefer a rated solid connection, just me. Between the house system and the starting system is another story and that circuit should be sized right and fuse or breaker protected. But if you put a low amp breaker or too small of a fuse between the starting batteries you may never know if it's open. I mean, a properly sized breaker might work fine but if for whatever reason it opened you'd be cranking off one battery. High amps often occur during cold weather and I wouldn't want to be crawling around looking for a problem if the thing had tripped causing the vehicle to struggle when starting. It's why I used a solid terminal block mounted in a fairly easy spot to reach for maintenance. You still have to be careful because after disconnecting the lead because it's still hot. I just used longer leads than stock going from the terminal block so it's easier to drop my 6.0 batteries now. Even with that, I generally just disconnect the battery after dropping the box. YMMV

[bonedoc]

Good info......thanks

[unreng]

install a blue sea switch on the battery ground instead of the battery positive - https://www.sportsmobileforum.com/fo...tml#post300198