Restoring - General discussions that span across many different groups of years and models > Misc Items
Headlight Change TSB Article
WT8095:
The calculation was purely informational, to show everyone how much more current the higher wattage bulbs will draw.
There are too many factors for me to second-guess Ford's engineering on what size of alternators were installed for each application. But since they used 38 & 42 amp alternators, it suggests they were working in a realm where a couple of amps may indeed make a difference. I would venture to guess issues encountered would tend to be more towards lack of charging, as opposed to say overloading wires or tripping breakers/fuses. Those are my opinions; I don't have any evidence to support them.
Here's one more thought: The higher wattage bulbs on low beam draw the same current as the low wattage bulbs on high beam. So if Ford designed adequate capacity to drive indefinitely with high beams on (original bulbs), there shouldn't be any problems using only low beams with the newer bulbs. Using the newer bulbs on high beam is where you start exceeding the original design capacity. [for two-lamp systems]
67gta289:
--- Quote from: WT8095 on March 09, 2016, 11:42:08 AM ---Here's one more thought: The higher wattage bulbs on low beam draw the same current as the low wattage bulbs on high beam. So if Ford designed adequate capacity to drive indefinitely with high beams on (original bulbs), there shouldn't be any problems using only low beams with the newer bulbs. Using the newer bulbs on high beam is where you start exceeding the original design capacity. [for two-lamp systems]
--- End quote ---
However the high beam feed (switch on floor) bypasses the headlight switch (with built in breaker). The additional draw through the switch might be a contributing factor for cycling switches. It would be interesting to see if the service switches after this date were a different revision and had more capacity.
When I get some time in a few weeks I'll do some testing with a couple different switches, to determine the time-current curves we are talking about.
67gtasanjose:
--- Quote from: 67gta289 on March 09, 2016, 11:52:06 AM ---However the high beam feed (switch on floor) bypasses the headlight switch (with built in breaker). The additional draw through the switch might be a contributing factor for cycling switches. It would be interesting to see if the service switches after this date were a different revision and had more capacity.
When I get some time in a few weeks I'll do some testing with a couple different switches, to determine the time-current curves we are talking about.
--- End quote ---
[/color]
I believe the later headlight switches allow the parking lights to operate in all switch positions, meaning the parking lights will stay on with the headlights too.
My understanding is 69? and older, the park lights shut off when headlights turned on. Maybe 68 & older, I'm not absolute on this.
67gta289:
--- Quote from: 67gtasanjose on March 09, 2016, 12:05:05 PM ---[/color]
I believe the later headlight switches allow the parking lights to operate in all switch positions, meaning the parking lights will stay on with the headlights too.
My understanding is 69? and older, the park lights shut off when headlights turned on. Maybe 68 & older, I'm not absolute on this.
--- End quote ---
Good point - the 67 and older (perhaps 68 as you mentioned) headlight switches also had to handle the tail light load. The front parking lights were off (load not included) when the headlights were on.
My test would be 67 specific in terms of load. But I would test each switch that had been collected over the years.
196667Bob:
Obviously, some Engineer at Ford had the "Bright Idea" that the 1968 bulbs (C8's) and slogan had run their course, and it was time to take illumination to "new brights" - err, I mean heights. Sorry, but just couldn't pass this up. Once in a while, we have to "lighten" things up.
Bob
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version