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I have a question about my "brand new '48 Deluxe Eight". The headlights cycle on and off much like the circuit breaker is opening and closing. I have measured the total current in both high beam and low beam operation, the current flow is in the order of 20 amperes total with the low beam having a slightly lower current. That would be well within the nominal range. There does not appear to be any transients in the reading but since the test was rather short the lights remained on throughout. When I'm out on the road the ammeter occasionally has the heebie-jeebies when the lights are ON and rock steady with them OFF. I suspect the poor regulator is trying (but failing) to keep-up with the potential of an ON/OFF 20 amp transient load. The question I have is how does one remove the chrome outer switch cover to gain access to the nut that secures the switch/circuit breaker assembly to the dash. I'd rather ask before I break something. I would like to remove the assembly and run a few 'under load' bench tests with the current circuit breaker and with a modern unit as a comparison.

To date I've checked the beam selector 'toe-switch',and inspected for chaffing . . . all is well. I've added temporary fuses in the low beam circuits (one for each), the fuses are being used as 'tattletales', but they too are in good shape.

G'day DavidPackard,
to PackardInfo, but sorry I can't help with your query, although I'm sure someone who can will be along soon.

But I do want to invite you to include your "brand new '48 Deluxe Eight" in the Packard Owner's Registry here on PackardInfo!

The switch assy removes from the rear. Chrome stays in place. One special nut is located next to the headlight switch and is sort of hidden between it and the next switch over. The other end nut is between a couple of smaller or less congested switches and more easily seen. You will most likely have to drop the vent control assy for access and to allow the assy to drop down.

The breakers have been known to lose capacity with age but also don't forget the breaker also protects the parking, dash, tail, license, and trunk lights. A short to the body at one of the grommet penetrations in the trunk or fenders is a possibility as is the insulation shrinking back or cracking off where the wire enters the shell at one of the lamp sockets. The loom in the trunk is a known area that has been damaged by things sliding or hitting it. The license light wire goes thru the trunk floor and that grommet is frequently hard, damaged or missing.

Any damage anywhere could allow a short and the breaker will cycle until vibration might move the wire or the breaker fails.

I'll take the liberty of borrowing a couple of photos posted by BDeB showing the nut locations.

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Thank you HH56;

If I understand your explanation correctly all of the switches are mounted to a sub-structure that itself is mounted to the chrome cover with two nuts that have a slotted screw driver slot. Once the switches and sub-structure are released from the chrome cover each switch may be removed by the single attachment nut. I presume that the dash is between what I'm calling the sub-structure and the chrome cover/trim.

I understand your comment about the heater/defroster & air control unit. For such a large car, why is it always a challenge to work under the dash?

To date I have not found a transient path to ground, but I understand that my tests have been static, that is, the car not moving. I will inspect all wiring in the trunk . . period. All of the harnesses have been replaced 14 years ago.

Thanks again . . . oh one more question.

Do you think the head light circuit breaker could be swapped 'in situ' thus limiting the disassembly? It would appear that two hex nuts hold the circuit breaker to the Micarta back panel of the switch.

dp

The dash does surround the chrome piece and may come down as far as the speaker area. The chrome piece is mounted to the dash metal along the top or sides & maybe a couple of screws or bolts at the bottom as well. Nothing directly between the chrome and switch sub structure. Forgot to mention there is a support hook for the radio bottom which hooks somewhere around the switches. It may actually be hooked to the switch sub structure. If so, that will also have to loosen or come off to remove the sub structure.

I've never tried changing the breaker on that type dash so not sure how accessible it will be. The radio case sits very close above the switches so it may cause some access problems. Be careful with pressure on the actual bakelite plate if you try changing in place. Some of those old pieces are fairly brittle or have cracks and will not take much.

for including not just your '48 Deluxe Eight Touring Sedan but also your '54 Cavalier Touring Sedan in the Registry. A fine pair!

The '48 circuit breaker is replaceable without removing the switch. Modern breakers appear to have the same geometry as the historic examples, so availability is not an issue. The breaker does not have a built-in mounting bracket so you might have to shop around. I use DelCity.Com for my automotive electrical materials (switches, wire, shrink tubing, connectors). I did remove the front seat cushion to make it a bit easier to get comfortable on what I was expecting to be a long job . . . it wasn't . . . long that is, but I could never find a good place for the 'string light'.

The modern unit operates at least 30 degrees cooler than the original item (135 F v 165 F), and the modern unit data was recorded at a higher outside air temperature than the original which matters with circuit breakers. Only the wire connections with 'bullet connectors' need to be removed so remember with color wire goes where.

So far so good. I'll re-post if the diagnosis was wrong, or the modern unit isn't up to the job. I measured about 16-20 amps passing thru the breaker (2 headlights, 2 tail lights, 1 license plate bulb) and installed a 30 A modern unit. If the Packard original unit was marked that ink left the station long ago. I've also read that circuit breakers have a finite life if they are asked to open and close. One source indicated about 50 cycles before the arcing at the contacts renders the breaker useless.

dp