Catalina - Capri - 25s International Assocaition Logo(2006)  
Assn Members Area · Join
h.jpg Home.
a.jpg Association Forum
s.jpg Ships Store
c.jpg Cruising
r.jpg Racing
t.jpg Technical Tips
g.jpg Photo Gallery - New
o.jpg Boat Search - Updated
m.jpg Manuals & Brochures
3rdrpt.jpg Swap Meet
l.jpg Links
f.jpg Officer Flag Line & Staff
b.jpg Bylaws & Constitution
 
1.jpg Members Area
1.jpg Join the Association
 
Notice:
The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.
 
Association Forum
Association Forum
Home | Profile | Register | Active Topics | Forum Users | Search | FAQ
Username:
 Password:
Save Password
Forgot your Password?

 All Forums
 Catalina/Capri 25/250 Sailor's Forums
 General Sailing Forum
 Rewiring your boat		  New Topic  Reply to Topic
 Printer Friendly
Author  Topic Next Topic  

Voyager
Master Marine Consultant

Member Avatar

USA
5392 Posts
Initially Posted - 09/13/2025 :  11:44:34  Show Profile  Reply with Quote
Many folks like myself have rewired the 12VDC systems of their boats. With many new owners here, folks try to determine whether and when to upgrade or replace their systems. Your best indicator is when lights start to flicker or fail, outlets go bad, or your VHF and music systems start crapping out, it’s time for a redo.

Catalina did a great job with then current 70s, 80s, and 90s technologies. Crimp connectors, tinned stranded wire, glass fuses (then plastic 2-prong fuses), toggle switches, and shrink tubing. They worked great and lasted for decades.

Because it’s 12V, in order to drive lighting and fan motors with enough wattage, they needed to provide high gauge wiring (10, 12, 14 AWG) to avoid power losses in the cables.
Now with LED lamps that draw around 20% of the power of incandescent lights, current demand is less, so replacement wiring can be made thinner and lighter in most cases.
Four sets of cables can be reduced: deck lights, cabin lighting, navigation lights, and mast lighting.

Wire gauge is calculated by estimating the current requirements given the round trip distance of your circuit. For example, 14AWG wire runs the cabin lights. Starting at the panel, the cable runs along the hull-deck joint on the port side running three to four portside lamps, then it turns around in the Vee berth running along the starboard side hull-deck joint all the way back into the quarterberth under the cockpit.

With LEDs, you can replace this with 16AWG cable with no losses.
The forward red-green navigation lights and the mast lights also run up the port side hull-deck joint, and due to less current, these cables can be made 16AWG.

For radios, VHF, and fans, I would not reduce the wire gauge. For 12VDC outlets, I might consider increasing the wire size (8 or 10AWG) since AC inverters and Bluetooth speakers can pull 10-20A.

New crimp connectors can be purchased with built-in shrink tubing to better waterproof the metal to metal connections. Ratcheting crimp tools make more secure and positive connections between cables and connectors. A friend recommended this self-stick vinyl tape to cover the connectors where shrink tubing didn’t do the complete job.
See : DEI Quick Fix Tape

There are lots of options for replacement of the old plastic cabin lighting including touch switch LED fixtures and LED reading lamps and spots.

New switches with built-in fuses can be purchased for your existing panel, or BlueSea can provide replacement panels.

In my case, I started with the switch panel, the battery, the engine, and solar charger first about ten years ago. I added fuses to all 3 connections to the battery, each on its own circuit. I ran 8 AWG to the outboard, and 10 AWG to the panel. Solar needs 5A so I added a 10A fuse with 14AWG wire.

I completely rewired the panel with new wiring, switches and fuse blocks. Rather than replace the panel, I decided to recondition the components. I added several 12VDC plugs by the panel, and also up near the head.

I can run a 200W inverter for small AC loads when I’m not at the dock.

You can rewire your entire boat over the winter like I did, or you can do one section at a time. It’s a great investment if you plan to keep and use your boat for the next several years, or even decades.
Bruce Ross
Passage ~ SR-FK ~ C25 #5032

Port Captain — Milford, CT
   Topic Next Topic  
 New Topic  Reply to Topic
 Printer Friendly
Jump To:
Association Forum © since 1999 Catalina Capri 25s International Association Go To Top Of Page
Powered By: Snitz Forums 2000 Version 3.4.06
Notice: The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.