Adding Turn Signal Switch To My '51 Chevy 3100

[Jasper4247]

I am rewiring my 1951 Chevrolet 3100, and retaining the 6 volt system. I am adding turn signals to the truck, and purchased a turn signal switch from United Pacific. The instruction sheet shows that I have to run a wire from the + terminal on the 3 prong flasher to the battery with a 15 amp in-line fuse between. 

Can I just run the wire (with the in-line fuse) to the ammeter instead?

Also, regarding the in-line fuse: This will be 16 AWG wire. I see some in-line fuses advertised as being 12 volt. I did not think that voltage mattered in a fuse, but was the amperage that mattered. Am I wrong? Can an in-line fuse advertised as 12 volt be used in a 6 volt system?

 

 

[Ben Bruce aka First Born]

Jasper, the power [+] wire can come from anywhere power is available.  Either switched or not, your choice.  Fuse does not know volts, only amperage.  The fuse is there to protect the wire and should be as close to the source as practical.  

 

  Ben

[Jasper4247]

Thank You Ben; I appreciate it.

[Stude Light]

My turn signals are hooked up so you have to have the ignition switch or key “on” for the turn signals to work. I did it this way as I won’t be using them when the car isn’t running and no worries about a dead battery if someone bumps the lever when the car is parked. My brake switch is wired to the battery or ammeter since you may want that to work if the car is turned off and it’s a momentary switch so it’s not like you can leave it on.

[Jasper4247]

Good points Stude Light. The instructions do show the brake switch wired to the battery - again, I would probably route it to the ammeter.

Thank You.

[pfloro]

Thank you Jasper for retaining the 6 volt system...! 

[Jasper4247]

Haha. You bet pfloro 🙂

[Jasper4247]

A question regarding ground straps.

 

The battery in the truck is in it's original position under the passenger side floorboard. There is ground strap from the negative post of the battery to the frame. There is another ground strap from the rear of the starter to the frame ( I assume this is for an engine block to frame connection). These are all of the ground straps currently on the truck; should there be an additional ground strap from the frame to the body, or from the engine block to the body?

[rocketraider]

If those ground straps are sized correctly for 6V they should be adequate. 0 or preferably 00 gage wire. These may also be braided steel straps. Not sure what the trucks had in those years.

[Jasper4247]

Thanks rocketraider. They are currently braided steel straps.

[Bloo]

The body should be grounded somehow. I'll bet there is a smaller strap somewhere or a wire. It doesn't need to be as big as the others, because as you mentioned you have starter >> strap >> frame >> strap >> battery. That is the return path for the starter (and the generator) and that is where all the current is. The body ground is just for stuff in the body (lights, gauges, etc). It matters, it just doesn't need to be as huge because of the lower current.

 

Fuses don't care about voltage as you suspected. Current is current. You worry about voltage ratings on fuses when the voltages get much higher, and flashover could occur. In other words, not in 6 or 12 volt cars. A lot of the old glass fuses used in cars were rated for up to 250V. One thing to consider is that a 6 volt bulb would need twice the current if it is the same wattage as a 12 volt bulb, so in some cases higher current fuses might be needed on 6 volt cars for similar duty. It is typical to load a fuse to around 75 or 80 percent, although not super critical. It is mainly there to protect the wire, and to prevent an overheated wire from starting things on fire.

 

Edited May 7, 2023 by Bloo (see edit history)

[Jasper4247]

Thanks Bloo.

 

Actually, the issue of grounding lights, etc. is what I was concerned about.

I will probably just add a frame to body ground connection somewhere just to be sure, before I get this rewire done.

[Jasper4247]

Quick question concerning the ammeter. I spent all day twisted like a pretzel underneath the dash disconnecting all of the old wiring.

I will be making several connections to the positive terminal of the ammeter, and I just want to be sure - as one is looking at the back of the ammeter from under the dash, is the positive terminal the one on the left?

I tried to see if there was any indication for + , but did not see anything.

[Bloo]

Well.. I don't know the answer. If you get it backwards though it's easy to tell. It reads backwards.

 

Accessory loads go to the generator side. I assume that's what they call (+) because it is more positive than the battery. Chevrolet connects the horn to the battery side. I don't know for sure why, other than guessing, but they do.

[dodge28]

You can replace the inline fuse wire with a 14 gauge wire or larger. Use power from the Ameter Battery side.  You have enough ground wires but if it makes you feel comfortable add a 10 g ground. 

[Jasper4247]

Dear fellow AACA forum members, especially those who were kind enough to respond to my question.

Apparently, I have committed an egregious error by posting the same type of question on the H.A.M.B forum with the intent of getting all the input that i could get.

because of this, it was suggested that I did not find you good people believable. Please know that is not the case; AACA has helped me now and before. Sorry if I offended anyone.

 

 

[Bloo]

If that is some kind of an error, it's news to me. I guess I wouldn't know because I am not registered over there.

 

[rocketraider]

1 hour ago, Jasper4247 said:

Dear fellow AACA forum members, especially those who were kind enough to respond to my question.

Apparently, I have committed an egregious error by posting the same type of question on the H.A.M.B forum with the intent of getting all the input that i could get.

because of this, it was suggested that I did not find you good people believable. Please know that is not the case; AACA has helped me now and before. Sorry if I offended anyone.

 

 

I'm also one who likes to get different inputs. NO SINGLE PERSON OR GROUP KNOWS EVERYTHING. No matter what they tell you.

 

The tricky part is figuring out who knows what they're talking about and who doesn't. I know very knowledgeable people on several different forums. I also see plenty of posers and bs artists.

 

One of my powerplant training talking points was that a new Operator should try to learn from all experienced Operations personnel, and then use that knowledge to develop a way of doing it that worked for himself- while staying within accepted guidelines.

 

I think the same applies to us as we learn about and try to fix our old car woes.

[Ben Bruce aka First Born]

I CONFESS!!!😁😁

 

  Jasper, the post I did was meant as " tongue in cheek" .   Trying for a little levity?       

  Having said that, I DO believe the answers will be substantially the same.

 I have found when an an automotive electrical vendor says connect to battery and use the +, they mean any convenient "hot" connection point.  It seems to be most difficult to get our thoughts across on the written page [ forum] as well as in person. The answer to the question is usually not instantaneous as it would be in person.  The answer to your first question is "yes."  Me, I would try finding a circuit on the fuse box, assuming the truck has one, to use. If none available, at least use a + [ hot] post there.

 

  Ben

[Jasper4247]

The truck does not have a fuse box, only the original two glass style fuses on the firewall for the tail light and stop light, hence my question about in-line fuses. I think I am clear now on the hot connection point. You are right, I was confused with the "to battery" designation on the schematic/drawing. 

Thank you Ben.

[EmTee]

On 5/10/2023 at 7:56 PM, Ben Bruce aka First Born said:

I CONFESS!!!😁😁

Troublemaker! 

[Ben Bruce aka First Born]

2 hours ago, EmTee said:

Troublemaker! 

 

  Dirty job. Some one has to do it!🤣

 

  Ben 

Edited May 12, 2023 by Ben Bruce aka First Born (see edit history)