Thanks Chuck, I missed this one. But my reply to the others this morning covers the points, I think.
Cheers, Randy Sent from my iPhone > On Aug 11, 2022, at 21:21, CHARLES SCHEAFFER <[email protected]> wrote: > > Hey Randy, > > Strange problem. Something is creating a dead short to blow the fuse. The > lights have a ground and one hot wire each. I'd be curious if the dome has a > metal ring and looking to see if the hot bulb tab is touching the metal ring > or the dome screw. You can insulate it with electrical tape or some liguid > nylon paint made to isolate electrical terminals. > > https://www.walmart.com/ip/Plasti-Dip-Liquid-Electrical-Tape/16888975?wmlspartner=wlpa&selectedSellerId=0&adid=22222222222009616975&wmlspartner=wmtlabs&wl0=e&wl1=s&wl2=c&wl3=10356703939&wl4=pla-1103084903071&wl5=&wl6=&wl7=&wl10=Walmart&wl11=Online&wl12=16888975_0&wl14=liquid+nylon+coating+electrical+tape&veh=sem&msclkid=4568518b85b11293c354337e43110c92&gclsrc=ds > > > Chuck > > >> On 08/11/2022 8:10 PM Randy Stafford via CnC-List <[email protected]> >> wrote: >> >> >> Hello Listers, >> >> I’m in need of your sage advice or at least hypotheses on an electrical >> problem. >> >> Here’s the background. Late last season my starboard running light bulb >> burnt out. It was a simple incandescent bulb, and the fixtures were >> probably original. So I thought hey, why not replace all three running >> lights with LEDs. In the process of doing that, I accidentally dropped the >> port fixture’s dome cover to the bottom of my slip (no chance of recovery; >> zero visibility). So, shit. I buy three new fixtures which have the same >> hole pattern as the old ones but of course take different bulbs so I had to >> buy LED festoon-style bulbs too. What started out as a simple $1.50 bulb >> replacement turned into a $150 project. And of course the new fixtures’ >> bases are thicker than the old, so I had to get longer stainless screws and >> drill and tap deeper holes in the stemhead casting. >> >> Well, after getting everything back together I discovered the running lights >> circuit is blowing its fuse within seconds of switching it on. But only >> when the dome covers are screwed on to forward fixtures (the new stern >> fixture including dome cover screws into the teak taffrail and causes no >> problems). I’ve now isolated the misbehavior to screwing the forward dome >> covers on. If I leave the covers off, the LED bulbs burn all night. I can >> press down on the fixtures and twist the LED bulbs around no problem - none >> of that causes any contact that shorts the circuit. If I put the covers on >> but don’t screw them down, the LED bulbs burn all night. But as soon as I >> screw those forward covers down, blown fuse. >> >> I’ve pulled the fixtures and looked carefully again at all the wiring, >> including in the forepeak under the deck. There is no pinched wire or cut >> insulation. The wiring to the fixtures goes through different (and much >> bigger) holes than any of the screws do. My heat-shrink butt connections >> are tight. As a short-term solution I just bought some nylon screws to hold >> the covers down. I haven’t tested that yet, but hopefully it works. >> >> Meanwhile I’m pretty mystified. Any theories? >> >> Thanks, >> Randy Stafford >> SV Grenadine >> C&C 30 MK I #79 >> Ken Caryl, CO
