Hello all,
I have installed turn signals om my 1924 T, using the following diagram supplied by Frank Harris.
It works great when I use a plain wire from the flasher unit to the center pole of the switch. However, when I replace that wire with a warning tell-tale bulb, the bulbs in the taillights barely light up at all. Strangely enough, the smaller the tell-tale bulb, the less light I get at the taillight. I have been careful to wire the signal to the brighter of the two filaments in the taillight bulb.
Does anyone have any idea why this is happening?
Thanks all,
Bob
Your tail lights are in series with the tell tale bulb. That increases the resistance in the circuit. I'm not quite sure how the tell tale bulb should be connected, but it is not to replace the solid wire. Perhaps you need two tell tale bulbs connected from each of the two side poles of the switch to ground. That would put the tell tale bulbs in parallel with the front and back lights on each side and you would also be able to see which side is flashing as in a modern car.
Norm
Norm,
I also tried to wire the warning bulb along with the wire (as shown in the diagram above) and the warning bulb would not light up at all.
There are no signal bulbs in the front, only in the rear.
Could the above diagram be in error?
Bob, you did'nt say if 6 or 12 volt, I used #12 wire to all my lights on the 6 volt system also a dedicated ground to all lights then to frame. They work great. Grounds are a problem on T's a lot of the time. KB
Looks like the bulb should be wired across the flasher. It won't work as is.
Keith,
All 12 volt, 16 gauge wire.
I'm not sure it's a ground problem, as both the running and signal lights are very bright when there is no warning light.
Ralph,
I can try that and get back to you -
Thanks, Bob
Bob,
The way it looks to me is that the push pull switch is for 4-way, and that the Double Pole switch should be the center off type or else one is going to 'blink' all the time.
The tell-tale as its own line throws everything on a branch into series connected, and with all bulbs being rated 6, they now see 3 which means they would barely even glow. You are either going to need no tell-tale, two tell-tales, or a little diode work, or change that flasher out to one with three prongs and use the 'pilot' to get your tell-tale. Or, change to a double pole/double throw center off switch and use the second set to get the tell-tale single lamp circuit. (Power leg to center, jumper both outputs on the second side, go to tell-tale lamp which is then wired to ground.)
Now, I walked the sketch circuit out in my head and not on paper so may have gone too quick, but that is what I think I 'see'.
Ralph,
I tried to put the bulb across the flasher unit - the warning light lights up, but will not flash.
George,
Thanks for your reply. I should have added in my original post that I did not include the push switch for a 4-way flasher.
The three prong flasher unit looks as though it might be the least amount of wiring involved out of all the scenarios. How would that be wired? A leg to the pilot, and the socket to ground?
Bob
I meant to say, a leg from the bulb socket to the pilot terminal, and the bulb base as ground...
Bob,
This circuit works for me. I used relays to keep the lamp amperage off the Model T Headlight Switch. I also thought it might imitate what someone might have done in 1916. The circuit is set up for power feeds in front and rear to keep voltage drop down.
I believe George has the best and simplest solution. Below is a schematic of what he suggested. The switch is a double pole double throw switch commonly refered to as a DPDT switch.
Ratshack used to sell a 10 amp variety for a few dollars.
schuh
Thomas,
Thanks for that diagram-
I have a separate vintage stoplight, so I would like to try to keep the taillights as running and signal only.
I'm thinking I might try switching to a 3 prong flasher unit and see how that goes....
This is the circuit I wired using a 3 terminal flasher. I installed a second lamp socket in my housings so I would have brake and signal in the same unit. Works great for me.
Sam
Bud,
Would a 3 prong flasher also do the trick? I'm trying to cut down on the number of wires back there, and using that flasher might add less wires?
Some years back, I had one of these, Mr. Harris was most gracious to talk to me on the telephone and walk me through a similar problem, is he still around?
I had a three prong flasher unit on my bench already, so I put it in and it solved the problem- everything is now working as it should.
Thank you to everyone for your suggestions and help.
I predict this thread will become very useful to others that want to add signals to their car----
Bob
Bob,
Schuh is pretty darned good at this stuff, I just play around until something works
I could be wrong here, but my thought is that the 'P' terminal on a 3-prong HD 6V flasher is a mechanical internal slave to the other two prongs...meaning, no bleed thru to the tell-tale lamp unless the flasher is actually flashing. I 'could' be totally wrong on this thought. Would also imagine you then need to pay attention to polarity on the other two poles when you wire it to prevent the bleed through. They should be marked B-L-P with 'B' being battery.
Like I mentioned Schuh can just talk this stuff through without sketches...I always have to sketch and test
Bob, lol didn't see your post...I had left it open after reading your question to Bud (Schuh)
Guess you just confirmed my thought.
Indeed-
Yet another forum success - thanks again!
Bob
You can use the two terminal flasher shown in the diagram. Leave the solid wire from the flasher to the switch. Connect the Pilot Lamp from the flasher to a good ground. This puts the pilot in parallel to the other lights.
I prefer a sonic device to the pilot light. Keeps from leaving the T/S on when not in use. I use a Mallory SC628 SONALERT 6-28vdc. I got it from David Riddle Co. 800-544-3746. You wire it in with a couple cheap diodes like Sam (Pops) shows except using the alarm instead of the light. You can wire it so it will be quiet when the brake is on, like at a traffic light, by running the - terminal to the brake light wire instead of ground. Works great. They will send along a diagram with the Sonalert.
Had to think back a bit but I needed to connect the alarm's neg. terminal to the brake switch wire (as described before) because I have bulbs that use the same filament for brake light and T/S. Otherwise putting on the brakes sounded the alarm.
My first thought when I read the topic was "Bursitis in your left elbow?"
But I decided to let the more serious minded solve the problem before giving my smart### answer. Especially since I have never put turn signals on an antique auto. I do use hand signals a lot.
Drive carefully, and enjoy, W2
Arm signal for right turn not real obvious with top up, especially at night.
I've been advised of a correction by our resident electronics guru. The pilot wired to ground in this circuit won't work. Well, it will work but it works all the time.
So, forget that last drawing.
Thanks John.
I think you were on the right track Ken. If one placed a SMALL bulb across the flasher terminals then only a small current would flow through the pilot bulb when the flasher was open which would be when the forward and rear lights were OFF. Thus the pilot light would be OFF when the other lights were ON. The only thing is that the pilot bulb would need to have a much smaller current draw than the other lights or the flasher would not flash because too much current would be diverted around the flasher and it would not heat up and flash. I like the Sonalert "beeper" device better and since those tend to draw really small amounts of current, placing a Sonalert across the flasher probably would work fine but then you would get the beep sound when the lights were off during the blinking cycle but many early 60's cars had blinker pilot lights that in fact worked exactly like that.
Back to the original drawing: if you had moved just the pilot bulb's right hand wire from the switch and put it on the left leg of the flasher, all would be good.
rdr
Ralph,
I tried that and it didn't work. The warning light stays on constantly, and does not flash.
The difference in cost between a 2 prong and 3 prong unit is minimal- why not just scrap the above diagram and correct it, using the proper flasher unit?
Bob
Please pardon the crudeness of my drawing....
Maybe someone else with good computer skills can "clean it up".
PS - this set-up works great for me-
Bob S.
Not disagreeing with the 3 prong approach but to make the light work when it is wired across the 2 prong flasher you need to have a very small current pilot bulb and a large current turn signal bulb(s).