Mercruiser 1981 Wellcraft wiring

[mkulin]

Ok so I have someones red haired step child for wiring. On a boat just so I'm clear (Ignoring interior lights and water faucets and such actually all house circuits) what is keyed on a boat and what is constant hot (managed by battery swithes)? Ex. horn constant or keyed? tilt trim constant? gauge lights? anchor lights etc...

 

[GA_Boater]

Gauge power is from the ignition switch. Only need instruments when starting or running motor.
Horn, anchor lights and TnT pump are always hot. Need power at all times, motor running or not.
Nav lights need power when underway Gauge lights may be ignition switched and tied into the nav lights. Instrument and Nav lights are used at the same time - Poor visibility/dark and underway.

 

[mjf55]

To add to GA_Boaters' list, if I may be so bold, is to make at least the automatic portion of the bilge pump always hot. I would argue that both the manual and automatic side should be hot.

 

[GA_Boater]

mjf - You may add.

The bilge pump is too important to leave off.

 

[Grandad]

On my 1972 era Mercruiser MCM120, the trim/tilt buttons work without the ignition on, but there is no trim position indicated until the key is turned on to power the instrument panel. - Grandad

 

[mkulin]

Thank you for the replies. Seems Im going to have to just rewire this thing the way I think it should be starting with the constant hot circuits. Im guessing anchor light and blower are constant as well. Additionally constant hots can be managed with the battery switch I presume. Good that I have restored 8 70's era corvettes not much difference.

 

[Grandad]

No Title

Thank you for the replies. Seems Im going to have to just rewire this thing the way I think it should be starting with the constant hot circuits. Im guessing anchor light and blower are constant as well. Additionally constant hots can be managed with the battery switch I presume. Good that I have restored 8 70's era corvettes not much difference.

Ya, when you've seen one corvette, you've seen 'em all. - Grandad

 

[mkulin]

Works like a champ started right up and everything works!!!

 

[garbageguy]

On my 1998 Wellcraft - nav, anchor lights, blower, are powered after the battery switch. Bilge pump always hot with float switch. Good to hear all your stuff is workin

 

[mkulin]

The only thing that runs straight off battery power is the trim/tilt on mine everything else after the switch. Some of it is operated off the key and some systems stay hot although I can shut off everything at the switch.