RC Receiver + Hot Battery Pack

[Curdster]

Any ideas on this? I swapped out my Nitro engine on an RC boat for a Brushless Motor + new compatible ESC. At the same time I upgraded my RC receiver, servo (rudder) and a new controller. All worked fine 6 months ago.
Came to test the boat for an outing this weekend and the receiver seems dead. No LED and the 4 X AA battery pack gets very very hot. Switched the battery pack with another and the same thing happens.
Could the ESC have blown the receiver?

[jrb43]

Not a boat expert so don't know if they're normally wired differently but:

Most (all?) electric cars eliminate the additional battery pack with what's called BEC (battery elimination circuit), so the receiver is powered directly from the main battery pack. I don't know how much of the wiring you changed when you went from IC to electric but is it possible your receiver has been getting two sources of power?

[clockworks]

As above, no need for a 6v receiver pack, although it can be done if you snip the red wire going into the receiver from the ESC.

I assume you do actually have a "big" battery pack for the motor? Trying to run a typical brushless from a 4AA pack is a no-no. It will draw try and draw more current than the pack can safely provide, overheating it.