So glad to find this forum!
We have been searching for our boat schematics everywhere... Does anyone have any idea where we could possibly find them?

your not going to find specific compplete boat schematics, but all hope is not lost. you can google search merc wiring and shecmatics xome up pretty easy for the atandard mer harness with includes ignition,m neutral swith and gauge senders. also google marine electrical color codes and that will give you marine specific stuf, pump wiring, blower, lights etc. ancillary stuff, stereo, cabin lights etc is kind of a crap shoot though.

what exactly are you looking for i just sold my 86 after 20years maybe i can help

Thanks phragle! We are actually ok with most everything. Just trying to find out where the hot water heater might be located. We think the previous owner might have eliminated it at some point and wondering if the wiring we found disconnected might be it.

Weldcrane! You had an 86 Excalibur Eagle? LOVE our boat but not much information out there so would love any information you have. Thanks for the reply!

hot water heater was mounted infront of the starboard engine on the platform the genset is on

That is exactly where we found the wiring that was disconnected. We planned on putting power to it this weekend to see if it lit up.
Thank you so much for your help!