Just having a small problem with my 67 roadsters front drivers side turn signal, the other day I noticed the left turn signal stopped flashing , figured it was just the bulb, replaced it , no change threw a new flasher in and still nothing. and when you pull the switch to the parking light position, the good front light and the rears come on, then when you pull it all the way to the headlight position, the tail lights stay on but the front marker goes out.

 

Check the banjo on column, or you need a new pull switch...

 

Dave,

I don't have an answer to the blinker issue but the front lamp is supposed to go out when you pull the light switch all the way out for the headlamps to come on. It can be rewired to stay on with the headlamps but that is not the way it came from the factory.

Leif

 

Check the ground on that light.

 

thanks guys, just assumed it stayed on, I will check the ground.

 

If it works in the park position, but not with turn signal it's not the ground. The park light and turn signal use the same ground. You'll have to follow from the bulb back through the connector at the front, through the bulkhead connector and up to the turn signal switch to see where you're losing connection. (assuming that the rear works). The most likely places are in the bulb socket or the connector just beyond. Double check that you put the correct bulb in.

 

I understand what you are saying there, but on dual fiament bulbs, it is possible for the power to feed back through the other filament to some other ground. As soon as you add power to the turn filament the light doesnt work or goes out. Thats why I would always check it first.

 

If you need a new switch, I just stuck one up in the parts section

 

Not really. There is no "some other ground" involved. The case of the bulb grounds to the same ground for both filaments. If the filaments were to short to each other, you would still get a glow when 12v was applied through either source. The fact that it works on park should eliminate the ground part of it. The easy way would be to measure for 12v (with black lead on meter to a good ground) on each of the two contacts in the bulb socket. You should have a flashing 12v with the turn signal activated on the turn signal contact. You can just move back toward the signal switch until you find the missing connection. Most likely in either the socket, the connector near that, or the connector at the firewall. He could also have a broken wire between the turn signal switch and the firewall connector. If the rear works and the park lamp works, you're down to that section of wiring. You have to find where it's missing before you can fix it.

 

OK, I guess we can kick this ball around a little if you want. Yes, there are two filaments with one ground, BUT, one of those filaments has considerably more resistance than the other. For that reason, the tail lamp will light using the other filament as a ground. You may see some glow from the other filament, but what you see with the lens on is light. Now, that current feeds back though the the other filament to what ever ground it finds. If you then apply voltage to the other filament, both of them go out because you have voltage on both filaments with no ground, and the whole thing goes out.

I am not sure this is what he is dealing with, but it is so common a problem, he needs to check it first.

 

Why would you have a ground until you put voltage on a filament then have no ground when you apply voltage. If the ground is bad neither filament will light no matter how much voltage you put on it. One filament (the park light) is working, so it has to have a ground. The other filament uses the same ground (through the base of the bulb). The filament can't find a ground somewhere else, it is either through the base or not at all. The 12v to the turn filament is what is missing.
I just hope the OP posts back what he finds the issue is, either way.

 

OK, The filament grounds through the wire to the other grounds on the line.

Lets say you apply voltage to the turn signal filament and there is no ground on that socket. The current flows though both filaments and then down the park lamp circuit wire to the filament on the other side and then on to its ground. If you then apply voltage to the park lamps, you overcome the voltage on that wire and both lights go out because they have no ground, but the lights on the other side will light normally.

 

Wow!
His park lights and rear turn signals work normally. If the voltage is going to both filaments with no ground they won't light. IF both filaments have voltage, they will both light if they find a ground. I know bad grounds can cause a lot of weird lighting issues, but in this case with what works and what doesn't it won't be a ground unless it's the one inside the bulb to the case on the turn filament. (he replaced the bulb).
I'm not trying to irritate you, and I'm not going to post any more until the OP comes back with what he's checked and what he's found.

 

The OP's post is a little confusing (to me). He said " the good front light and the rears come on, then when you pull it all the way to the headlight position, the tail lights stay on but the front marker goes out."

It sounds as though the park lamp is not lighting, as well as the turn signal not flashing.

 

That's what it's supposed to do. The first detent in the switch turns on the parking lights. They are the turn single lights and the tail lights. The second detent is head lamps and tail lights. NO MARKER lights. If your indicator light stays solid when using the turn singles it means a light bulb is blown on that side.

 

Read my post again, NM. I wasn't referring to the park lights going off when you pull the switch for headlights. He said " front marker" , not front markers. Markers is plural. As in more than one.

 

Haven't had a chance to work on the car, will do later today, to be clear, the front drivers side park/turn signal light, does not work at all. The other side works when you pull the light switch to the first detent, then goes out(as it is apparently supposed to) when you turn the headlights on.
When the drivers side turn signal is activated, the dash light stays on constant, as if there was a burnt bulb.

 

Sounds to me like the 1157 bulb is bad or not making contact or installed backwards.

 

If neither section is working at all that adds some of the possibilities mentioned earlier by wombvette. Just so you're clear, when you say the park/signal lamp doesn't work, that is two lamps in one. The turn signal is a separate circuit and has a separate filament that lights up from the park except for the ground. So if neither front light works, you either have two problems on the voltage side, or a missing ground.
Did you put in the proper replacement bulb, and did you position it correctly in the socket? A couple of other possibilities IF neither of the two filaments in that socket are lighting: check the connector just back from the buckets at the side wall, it may be unplugged or corroded. Measure for voltage there, if it's there go toward the bulb socket. If not, go the other way to the bulkhead connector and see if that's where you're losing it. I'm not sure why so many are afraid to use a voltmeter to check these problems, but if you have to go another way, buy a cheap 12v test light and see where you're losing it. If you have the voltage on the pins in the bulb socket with the negative lead of your meter or test lamp on a good ground, you'll know the ground is missing. You could also run a jumper wire from the bumper to the side of the base of the bulb and see if your lights work, that would also be an indication of a bad ground.

 

I checked the bulb, it does work, also checked for voltage in the socket there is non in either application, just headed out there now to try some more tests, thanks for all your suggestions, I will let you know how I make out.