Help diagnosing lights mystery

[Art and Barbara Levine]

Hello all.  On our C34MkI (#889), our bow running light, steaming light, and anchor light are all mysteriously out; however, our spreader lights and stern running light work.

We rarely use our lights, so I suspect corrosion or some other non-bulb problem.  What's the best way to diagnose this?  

Thanks,

Art and Barbara Levine
xmodlaw@aol.com

[Stu Jackson]

Art

Not a mystery.

Try the bulbs, try the contacts, try the fuses or breakers.  It's either behind your panel or in the wiring to the lights.

Step by step, inch by inch, row by row.

Basic electrical troubleshooting.

Buy Nigel Calder's Boatowners's Mechancial and Electrical Systems book.

Stu

[morgan4848]

I had a very similar incident with my boat.  The bow light would be on when I turned on the switch for the cabin lights.  It turns out the wiring for the cabin lights and the running lights is tied together by the use of blue plastic connectors better suited for trailer wiring than boats.  The connectors were corroded and shorted between the cabin and running light systems.  The connectors were located aft of the panel in the cabinet above the hanging locker.  I replaced them with butt connectors.  Solved the problem.

[Ted Pounds]

It's likely corrosion.  The connectors for the mast lighting are in the bilge and so are very prone to corrosion.  I had trouble with mine when I first bought "Molly Rose".  When I went to put a new plug for the wires at the mast step I found that all the crimp connectors were so corroded that when I took off the electrical tape they simply fell off the wires.  So I suggest you follow all the wires and replace the connectors, even if they seem OK.  Redo them with crimped and soldered joints and then make sure they are well sealed.  When you replace the joints take a good look at the wire.  On unsealed joints water can wick its way under the insulation and corrode the wire, sometimes to the point where it breaks inside the insulation. If the wire is corroded you'll need to replace it too.  That's what I also had to do with my mast wiring.  Make sure you use marine grade, tinned wire (Catalina didn't ) to preclude the problem from recurring.

Ted

One further note:  voltage at the fixture is not always a good indicater that the wiring is OK.  I helped a friend diagnose a problem with his bow lights.  We found the open circuit (light bulb removed) voltage to be good with the switch on.  But closer inspection revealed corroded connections that had too much resistance to let much current through even though they were connected enough to register on the voltmeter.  So if you want to check the voltage at the light do it with the bulb in the socket (easy to do with the bayonet bulbs on the Catalina).

[Paul Blumenfeld]

I'm planning on pulling the keel stepped mast for the first time.  I'm not finding any connectors for the wires?   Are there connectors under the mast and it has to be lifted to see them, or did the 1987 models have wires running all the way to the panel without any connectors?

Paul

[Footloose]

Paul,

My 87 has a connector that is in the bilge next to the keel step.  I doubt that it is under the mast as the weight of the mast on the wises would cut them.  As has been stated above this connector is prone to corrode and a PO may have taken it out to eliminate one problem.  Now you get to cut the wires to get the mast out.  I suppose if you see your wiring going under the step you could see if there is a connector under there when the yard lifts the mast.

Good luck,

Dave

[Ron Hill]

Paul : As Dave said, there should be NO wires under the mast.  The wires for the anchor, steaming and deck lights come out of the mast about 2 inches above the step and fwd portion of the mast.  They go to a connector that's in the small bilge fwd of the mast.
You may also have a VHF radio antenna, TV/FM antenna and wind machine wire to also disconnect.   

[Stu Jackson]

Art

Sometimes they split the wiring, so that one bunch goes to the black box waterproof connection and some wiring goes directly to the mast.  For instance, our steaming, anchor and deck light wires and the ground are simply butt spliced together at a point underneath the forward removable bilge section floorboard and wrapped in heat shrink tubing.  To disconnect for pulling the mast, the yard simply cut the wires and re-spliced them back together, while inside the black box was simpler to just unscrew wires on the mast side.  There is no "connector" per se, like you'd see on a deck stepped mast or like on the C25s.