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I just got done replacing the entire harness of my '41 110 with wire from Rhode Island Wiring. Can't recommend them highly enough! Very impressive quality product and helpful customer service.

The circuits I have tested thus far all work properly...even the clock, which was not previously working, is ticking away now! Surprisingly, it continues to run with the battery disconnected!

I have some questions:

1. The starter button turns the engine over regardless of whether the ignition key is "on" or "off". I can't remember if this was the case before I rewired. Have I done something wrong or should you be able to crank the engine over by pushing the start button with no key in the ignition?

2. The parking lights are not yet installed (waiting on painting the buckets they mount in). When I pull the lighting switch to the first position (parking lamps), I get 6.2 Volts at both front and rear parking lamp wires. When I pull the switch all the way on for headlights, the lights don't come on and the ammeter begins to swing from full discharge to zero and back about once per second. Is this because all the parking lamp and tail light connections have to be made before the front (sealed beam) headlights will come on, or have I wired something incorrectly?

3. I would like to add in-line fuses to both the windshield wiper motor and heater blower motor in case they fail at some point and put a large draw on the system. Can I use a standard 12Volt fuse harness available from the parts store or do I need something made for 6V. Also, how many amp fuse should I use for each of these circuits?

4. There is a new wire running back to the fuel level sending unit in the tank. Rather than cut and splice it, I'd like to run it all the way to the tank itself, but it looks like this involves removing the tank to gain access to the top. Is this a difficult job? Would appreciate any advice on how to remove the tank and, while its out, what would be a good way to clean/seal/restore it. It hasn't given me any trouble but I figure I should address it while the car is being put back together.

Thanks very much for any and all advice!

On the starter switch, the schematic shows it being powered from the BAT side of ign switch so active all the time. The engine will crank with the key off but only start with key on because the coil is fed off it's own terminal and only active when ign sw is on.

Don't know if that was a Packard exclusive or if other cars of the era also cranked at any time. Packard did change that on 42s when they went with the carb switch. Looking at the schematic, if the wire is long enough it would appear yours could be changed by moving the wire feeding starter switch from the bat side to the switched side of ign switch.

The headlight circuit looks to be the same as later models so front parking lights would have nothing to do with the CB cycling if disconnected unless one of the wires is shorted. The front parking lights should go off when switch is in position headlights are on leaving only the headlights and tail lights. If CB cycles only in that position I would suspect a short or problem in headlight or tail light wiring.

No specs are given on either wiper or heater for 41 but heater amperage was mentioned for later models and those were 20 amp fuses on 6v cars. A 12v fuse is fine. As to the wiper, it has a built in circuit breaker so you would only be protecting a short distance of wire if you added a fuse. If you do add one, I would start with a 20 amp. I have no idea of the current draw if the wipers bogged down so that may not be enough.

Someone else will have to say the difficulties on dropping that tank. I know it is not the most pleasant of chores on later models.

Thanks so much for your quick and helpful reply, Howard!

So my taillights are currently not connected..only bare wires. Just the headlights are connected. Would that explain the cycling on the ammeter and no headlights coming on when I pull the lighting switch all the way out as there is no "loop" to complete between the headlights, tailights, and lighting switch?

Everything else is working properly and there really isn't a lot of room to screw up the harness as it all plugs right in so I can't imagine where a short could be taking place. It all worked fine with the old harness and this new one just plugged in exactly where the old one was.

Where would you start looking for the problem if it isn't related to there being no tail lights currently installed.

I'm going with the assumption your headlight switch is the standard 3 position typically used with sealed beams -- off, parking, and headlight. If not, and it is the older switch with a 4th position there are other things to consider so the rest of the post might not be completely applicable.

If the 3 position, then the first on position feeds the parking lights and tail lights but no headlights. From the tail light terminal is a feed for dash lights and if the car has fog lights, that foglight switch also connects to the tail light terminal on headlight switch to feed the tail lights. I am assuming every thing works OK in the parking light position. The tail lights being disconnected would not affect anything unless the wire was shorted.

For the headlight position, the front parking lamps are disconnected. The tail lights and dash lights are still fed but the terminal feeding the dimmer switch and headlights is now active. If the CB is now cycling, the main thing that changed is the dimmer switch and headlights are added. The dimmer switch is a known source of sudden problems so just disturbing it to change wires could have pushed it over the edge if it was ready to fail.

Assuming it is OK, the dimmer switch gets the feed from headlight switch and then selects either the low or the high beam filaments. Both bulbs are in parallel so if something was mis labeled and got crossed that could cause the issue. I would verify the same terminal on each socket is active. The high beam terminal on dimmer switch also has a wire running up to the indicator light on dash. If that dash socket shorted it could cause an issue if the dimmer is selecting high beam when you turn the headlights on. Sometimes the insulation can be a bit short and the conductor can actually touch the grounded shell when the bulb is inserted and pushes the contact button back. That would be another thing to verify. Mash the dimmer switch once to change beams and see if the CB still cycles.

I am not sure if the 110 has the same switch as the senior cars but if so there is a resistor for the overdrive light on the switch. If your car has OD, that resistor has been known to get bent and short against the headlight terminal. If might be a good idea just to verify if the resistor is there OD or not and make sure nothing is touching.

Thanks again, Howard!

What is causing this "cycling" I am experiencing? I am not aware of any circuit breaker in the headlight circuit.

Packard calls it thermal protection. In modern terms it is a self resetting circuit breaker. If you look at the switch you will see a strip of metal running down the center for about half the length of the switch and between the side wire terminals. One end is connected to the switch fiber board and internal contacts and the other end stops below a small screw. That is a bimetallic strip which heats with current and bends. When a short or excess current causes it to reach the set point controlling the amount of bend, connection breaks and power is cut. When power is cut, strip starts to cool and eventually makes the connection again. That is the cycling part. It will continue cycling until the problem is corrected or the strip and contacts fail.

This is very helpful and I am tempted to cut out of work early and run the tests you described!

Just a quick clarification: With respect to the headlight dimmer switch, when you say "verify the same terminal on each socket is active", what exactly do you mean? What parts of the switch should I check with my multimeter and under what scenario/order?

The way the headlights are wired, there is the 3 pin socket at each bulb. If any of the labels on the two cables between the sockets and the single terminal strip was wrong, the bulbs might not be seeing the same thing. Just as an example one bulb might be getting power at pin 1 for one filament and the other bulb might be getting power at terminal 2 or 3 instead.

Since the parking light switch position apparently causes no problem, we will assume parking, dash and tail light wiring is OK and nothing is shorted. If those are OK I would concentrate on the headlights.

The easiest and first thing I would do is verify wiring at the headlight and dimmer switch visually and that none of the wires or terminals was bent or shorted. Turn on the lights and if no lights and cycling starts mash the dimmer switch to change filaments & see if the problem stops. If it does then check the dash indicator light and socket carefully. If no change then kill the lights and go to the dimmer switch again. Disconnect the wires on dimmer sw going to terminal strip on fender and try again. Cycle the dimmer switch with only the feed wire connected. If still a problem, dimmer sw or wire between headlight sw and dimmer sw is suspect. If no problem connect dimmer sw again and move on to the fender terminal strip. Verify the paper insulation between studs is all good and no shorts.

If you want to use the ohmmeter to verify sockets you will have to remove the headlight bulbs. Disconnect wires to both bulbs so all you have on the terminal strip are the wires from dimmer sw. Sockets are labeled with numbers or names. Pick one of the wires going to the left headlight socket and verify which socket terminal it goes to -- 1 (drive), 2 (pass), or 3 (ground) -- by connecting the ohmmeter to one wire and probe the socket with the other lead for continuity..If you can tell by color that is easier but that won't check that there isn't a short between two of the terminals or wires. Do the same to the right socket and make sure the same socket pin and wire is identified and will be together when placed back on terminal strip. If the existing markings are correct so that both wires will go back to the same place on terminal strip move on to the next wire and socket terminal and identify. When everything is identified or verified correct then connect and try again.

If it still doesn't work, something very strange is going on.

Thank you! This is very clear and helpful.

Looks like I'll be stuck late today at work but will try tomorrow evening and update you on the results.

Many thanks again for taking time to help me through this!

Howard,

I went into the garage late last night and followed your instructions to a "T" and had great success! I didn't find any overdrive resistor on the Lighting Switch, so moved on to testing the dimmer switch, which worked on low beam and shorted out on high beam. I traced it to the fender terminal block and found that while all the wires were connected correctly according to color, I had the green wires connected together on the stud that was grounded to the chassis, which is where all the black wires should have been grounded instead. Once I switched that around, it all works great!

Thank you so much for taking the time to respond to my question, and in such a detailed and accurate way. I am brand new to the old car hobby, this being my first classic car. It's folks like you, who take the time to teach and encourage others, that are keeping this great hobby alive and ensuring that interest in Packards will continue into the next generation.