12 volt prefocus bulbs

[Phil Waterman]

Hi Harry

Just this afternoon I replaced the 6 volt Halogen bulbs with some of the old prefocus blubs which I had done just what you describe of re-soldering the base and rotating them. Some of the bulbs also have the ring the wrong distance to the base which is corrected the same way.

But back to the 6 volt halogen bulbs, while they are a lot brighter than a standard Prefocus bulb and with a good reflector nearly as bright as a seal beam they have in my experience a short lived. I drive with my headlights on all the time (no mater what I'm driving) and the 6 volt halogens last about half as long as a 6 volt seal beam. Put the halogen in two trucks at the same time and the low beams of both failed this spring.

Photos below are some test that I did when I first installed the Halogen bulbs. 1st picture Halogen Left standard 2331 Prefocus right both LOW beam. 2nd is Halogen Left standard 2331 Prefocus right both HI. Type of mount is the 3rd picture

Halogen is brighter and tighter but shorter lived.

Cheers Phil

PS- All three of my trucks have 6 volt systems which have not given me any reason to change over to 12 volt having said that, all three trucks carry 12volt batteries as well to power radios and accessories . When I put the 261 engine in my C60S I was concerned about starting so I installed a marine battery switch will allow me to shift just the starter over to the 12 volt in an emergency to start. Think I've used the 12 volt for starting maybe twice.