Chassis Battery Disconnect

[wracinti]

I need to replace my chassis batteries. I will be doing it myself, looks pretty straight forward but want to make sure I have the chassis battery disconnect right. In my engine compartment to the right of the engine oil fill is a yellow switch that says "Buss MRCB" on top and "150A 48V DC max" on the right side of the switch. Is that it?

[twinboat]

There may not be a main battery switch. Main engine starter motors can draw over 250 amps and breakers or fuses are rarely used.

What your referencing may be the generator circuit breaker.

Make sure the shore power is unplugged and the house batteries are off. You don't need the isolator circuit connected.

For the chassis battery, remove the negative cable first, put it aside, and then the positive. You may want to stick the positive end in a glove, until re-connecting.

When re-installing, positive on first and then negative.

Remember, once the one cable is off, all of the energy is in the battery, not the ends.

[RJOL]

I'd also recommend that you take a photo of the battery layout, before you remove them. That way, you will be able to see how they are positioned and how they were hooked up...