New Fuse Block Configuration

[dcarlg]

I'm seeking advice because I want to get this right the first time. And properly protect my car, a BT7.

Project: replace standard fuse block with a Charlie Hart fuse block with 6 fuses. Can't seem to fit that seventh fuse due to space limits.

Proposed layout:

Fuse #1 to: Headlight relay and electric pusher radiator fan, 25 Amp, from: Brown wire from starter solenoid
Fuse #2: to: Horns, 25 Amp, from: same brown wire as above via short bus or jumper
Fuse #3 to: Fuel gauge/heater and turn signals, 15 Amp, from: switched white wire from ignition/coil
Fuse #4 to: Wiper motor and flasher unit, 15 Amp, from: same white wire via bus
Fuse #5 to: Stop lamp and fuel pump, 15 Amp, from: same bus
Fuse #6 to: Overdrive relay and radio, 15 Amp, from: same bus

Also, I plan to add in-line fuses near the license plate lamp and the overdrive solenoid. 10 Amp.

OK. I'm ready for comments, criticism or suggestions.
Thank you,
Douglas

 

[Deleted member 21878]

Douglass
here is what i did. i do not have an electric fan... yet. i used a set up from CG Hart as a guide.
first of all i wanted to leave the engine bay looking kind of normal. so i pulled a 14g wire from the 35amp side of the fuse block inside. i also pulled all the wires for that side of the fuse inside to my sub panel.

Fuse #1: OD relay 20amp
#2: Fuel Pump 10amp
#3: turn signal / fuel gauge / fan motor 15amp
#4: stop lamp 10amp
#5: flasher 15 amp
#6: wiper motor 15 amp
#7: phone and speaker inverter 5 amp
#8: driving light relay 15 amp

i also added an inline fuse to the headlight circuit per a wiring diagram i had bought.

a few pictures. forgive the wiring... this was still in the organizing stage.



Also, i did not change anything with the horns. they are the only thing on the top side of the original fuse block.

 

[Lin]

Just my opinion, but while I think creating more fused circuits is a good idea, I do not think that fusing headlights is smart. If I correctly understood what you did? Would not want to be driving on the road at night and have a headlight fuse blow.
Lin

 

[Keoke]

Lin:

That problem can be averted by having the head lamps and driving lamps independently fused and activated mine are,which lets me get home one way or the other--LOL

 

[Lin]

Keoke,
Of course, you are correct in the situation you describe. However, not everyone has driving lights. You do, and I do, but I see many more cars without them.
Lin

 

[Deleted member 21878]

Lin
i think i am missing something with your post.... which is not too tough for me.

My thought is that normally if a fuse blows, something has shorted. fuses lessen the chance for fires. i keep an extra fuse or two in the car. key is to make the holders, easy to get to. i think virtually every car since 1970 has fused their headlights including my daily driver. i would fuse them driving lights or not.

however, i do have driving lights that are on a different fuse.

 

[vette]

In the '50s & '60s Chevys had a circuit breaker built into the headlight switch. It was a bimetal type of deal and when the overload was cut off the bimetal would restore the circuit. The theory was that if the head light circuit shorted the bimetal would heat up and open the circuit then with the circuit off the bimetal would close and the lights would come back on until the overload heated the bimetal again and it would open. This effectively would allow you to drive home with blinking lights. There have been many cars since then that did not have any fuse protection on the headlights, this included our beloved LBCs. I can tell you that in the last year I have repaired the wiring harnesses on two cars because the dimmer switch shorted out and there was no fuse protection. One was on a Bugeye Sprite and it melted the harness all the way back to the ignition switch. It almost burnt the car down. Since I have seen this personally now, I will always put a fuse in the headlight circuit of any car that I am involved with building or repairing.

 

[Patrick67BJ8]

I'm seeking advice because I want to get this right the first time. And properly protect my car, a BT7.

Project: replace standard fuse block with a Charlie Hart fuse block with 6 fuses. Can't seem to fit that seventh fuse due to space limits.

Proposed layout:

Fuse #1 to: Headlight relay and electric pusher radiator fan, 25 Amp, from: Brown wire from starter solenoid
Fuse #2: to: Horns, 25 Amp, from: same brown wire as above via short bus or jumper
Fuse #3 to: Fuel gauge/heater and turn signals, 15 Amp, from: switched white wire from ignition/coil
Fuse #4 to: Wiper motor and flasher unit, 15 Amp, from: same white wire via bus
Fuse #5 to: Stop lamp and fuel pump, 15 Amp, from: same bus
Fuse #6 to: Overdrive relay and radio, 15 Amp, from: same bus

Also, I plan to add in-line fuses near the license plate lamp and the overdrive solenoid. 10 Amp.

OK. I'm ready for comments, criticism or suggestions.
Thank you,
Douglas

Do you have a 6 Fuse 7 Fuse Panel from Charlie Hart? There’s a difference. I installed o e of his Fuse Panels on my BJ8. I can post photos, etc.

 

[dcarlg]

Patrick,
It had 7 fuses, but the bottom fuse interferes with the harness/oil pressure line, so I removed that fuse from the block

 

[Patrick67BJ8]

Patrick,
It had 7 fuses, but the bottom fuse interferes with the harness/oil pressure line, so I removed that fuse from the block

BJ8’s getbthe 6 Fuse Panel because of that very reason. The first fuse panel Charlie sent to me was a 7 Fuse Panel and it wouldn’t work unless I recent the oil pressure gauge line plus turning it upside down because the green wires are on the opposite sides when compared to the earlier cars.

 

[dcarlg]

I am now reconsidering this project.
Several wires are too short for reach this fuse block and I can't find my wire stretcher tool.
I want a tidy end result, so maybe I'll look at other options.
Thanks for all the advice so far.
Douglas

 

[Patrick67BJ8]

I am now reconsidering this project.
Several wires are too short for reach this fuse block and I can't find my wire stretcher tool.
I want a tidy end result, so maybe I'll look at other options.
Thanks for all the advice so far.
Douglas

Did the wires fit okay on the old fuse block? Can you post a photo of what Charlie sent to you?

 

[Bob_Spidell]

re: "... I can't find my wire stretcher tool."

I this a thing? The only wire stretcher/puller tool I've seen is used for pulling vineyard wires taut.

 

[CaptRandy]

Vette, those bimetal fuses are used often in boat wiring. They come in various load sizes 15, 25, 40 amp. Might look at that for my headlamp circuit.

 

[dcarlg]

Bob,
It's a mythical tool that is needed when the wire is a little too short.

 

[Bob_Spidell]

Bob,
It's a mythical tool that is needed when the wire is a little too short.

Thought it sounded too good to be true, but I have used a wire puller before (might be overkill for a wiring harness):

https://www.amazon.com/Barbed-Smooth-Wire-Fence-Stretcher/dp/B01N5FU8FN

 

[Michael Oritt]

Getting your circuits fused is more critical than the esthetics of your engine compartment but if wires are too short for you then locate your fuse blocks on the rear side of the firewall.

I have two six position fuse blocks in my car--One for circuits that are bot all the time and the second for circuits that are energized with the ignition switch.

Hot all the time:

1. Headlights (yes, I think they need to be fused)
2. Driving lights
3. Horn
4. Side/dash/license plate lights
5. Auxiliary fan
6. Accessory plug (cigarette lighter)

Switched by ignition:

1. Windshield wipers
2. Turn flashers
3. Fuel pumps (one double-header wired to an on-off-on switch)
4. Heater fan
5. Brake lights
6. Spare

 

[RAC68]

Hi All,

As I see it, fusing critical high load components is a matter of good economics and safety. I appreciate that if a headlight is fuesed and the fuse blows it could leave you, and the headlight, disconnected and in the dark (as to its cause). However, the cause of the burned fuse could likely be found with minimum difficulty and the condition probably rectified with little or no permanent damage. However, the same condition which would cause a sizable headlight fuse to blow has a definite potential to result in a fire and easily burn up your wiring harness. So, would you like to install a fuse or a fire suppression system?

Just my thoughts when reading the responses,

Ray(64BJ8P1)

 

[Michael Oritt]

I agree with Ray and even if no fire results a short in an unfused headlight circuit leaves, at a minimum, a burned wire that must be repaired--probably a length of it will have been cooked and the insulation melted off at the source of the problem.

If the circuit is properly fused the wiring will hopefully have survived in at least good enough condition for it to show you where the short occurred and permit a temporary fix with perhaps nothing more than electrical tape/butt connector plus, of course, a replacement fuse.

 

[vette]

Doug, I agree with many here that it is valuable to fuse things separately and also to install fuses on things that are not fused. I am hoping that I am able to assuage your hesitation to follow thru with the idea. The first thing that I noticed in your original post is that I believe you are planning to use fuses that are rated much higher than necessary. I will give you a list in a moment showing the fuse sizes I have been using for more than five years with no trouble at all. Also in regard to having short wires, I will include a pic of how I extended/spliced out longer wire to reach the new fuse box location. I believe my installation especially at the old fuse holder location is rather neat. I got more green wire, made crimp splices that all lined up along side each other, then wrapped the splices with harness tape, (not to insulate them but just to bind them together) the put a black wire tie around the wrapped splices to keep them tidy. all the green wires then enter the cockpit thru a single hole in the firewall. Another pic shows the new fuse box inside on the air plenlum. These are the circuits that are controlled by the ignition sw so the hole fuse box is turned on by the ignition switch. There is another fuse box on the right side (passengers side) which is powered by the wire that was on the lower original fuse and it is hot all the time. These circuits are for auxilary stuff like driving lights, horn, radio, etc.
Here is the list of the size fuses that I am using for the different circuits:

Wipers --------------------------------------------------- 5 amps
circuit supplying Fuel Gage & Heater motor ------- 5 amps
Brake Lights --------------------------------------------- 3 amps
Fuel pump ------------------------------------------------ 5 amps
Overdrive ------------------------------------------------ 10 amps

I have 2 inline fuses behind dash supplying the dash gauge lights and one for the running lights. I sorry I can't tell you for sure their sizes but I think I have a 3 amp on the gauge lights and a 5 amp on running lights. Which is probably higher than necessary.

Good Luck.