Inline fuse in lieu of fusible link

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I would like to install a fuse in the fusible link what size fuse would you recommend in the amp meter bypass wiring diagram. The way I see it there should be one leading to The Loop through bulkhead and one leading to the alternator. I appreciate your responses.
 
I installed a 40A circuit breaker in the line from my alternator to the battery and a 30A breaker from the battery to the inside of the dash. No fusable links anywhere in my car.
 
DesertRat said:
I installed a 40A circuit breaker in the line from my alternator to the battery and a 30A breaker from the battery to the inside of the dash.
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Thank you very much and I don't know what a circuit breaker for a car looks like guess I'm just stupid and old if you have a pic I would appreciate it and would like to know part number thanks again
 
I bought an inexpensive DC amp gauge, started the engine, turned all my accessories "on" and got a max amperage reading. I bought a slow blow fuse 30 amps over my max and installed in line. Pics later if you want???

treblig
 
Treblig said:
I bought an inexpensive DC amp gauge, started the engine, turned all my accessories "on" and got a max amperage reading. I bought a slow blow fuse 30 amps over my max and installed in line. Pics later if you want???

treblig
Click to expand...
That would be really great thank you very much for your help
 
As long as the fuse does not exceed the ampacity of the wire then the wire becomes the "fuse"
 
scott657 said:
As long as the fuse does not exceed the ampacity of the wire then the wire becomes the "fuse"
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Yes you're right, I looked up the load carrying capacity for my power wire size and bought the correct fuse. I might still have a copy of that printout but you can find it on line pretty easy.

treblig
 
Well the slow blow fuses are not in my '69 Barracuda (background in last pic) but they are in my daughter's '59 Studebaker Silver Hawk. I installed a new 350 Chevy engine and didn't want to overload the old wiring. The Silver Hawk originally had a very rudimentary fuse box (2 glass fuses) so I installed an all new fuse control box and wired the great majority of the power through the new fuse box. I used one slow blow fuse for the alternator to battery connection and another for the main wiring to all car accessories (dash, stereo/radio, amps, lights, horn, AC, ignition, clock, gauges, etc). I used the DC amp meter to determine how many amps go through the alternator/battery wire under full load and to determine the load on the car wiring system under full load. My daughter is 17 and loves driving her car to school everyday!!:steering::thumbsup:.

I know it's not a Mopar but the car she originally wanted was the "Christine" car (she wanted a car with fins). The Christine car was just way to large so I got her the next best thing:

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The DC amp gauge was only $34 and I wish I had bought one 20 years ago. It takes all the guessing out of car wiring issues!!!
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Treblig
 
Treblig said:
Well the slow blow fuses are not in my '69 Barracuda (background in last pic) but they are in my daughter's '59 Studebaker Silver Hawk. I installed a new 350 Chevy engine and didn't want to overload the old wiring. The Silver Hawk originally had a very rudimentary fuse box (2 glass fuses) so I installed an all new fuse control box and wired the great majority of the power through the new fuse box. I used one slow blow fuse for the alternator to battery connection and another for the main wiring to all car accessories (dash, stereo/radio, amps, lights, horn, AC, ignition, clock, gauges, etc). I used the DC amp meter to determine how many amps go through the alternator/battery wire under full load and to determine the load on the car wiring system under full load. My daughter is 17 and loves driving her car to school everyday!!:steering::thumbsup:.

I know it's not a Mopar but the car she originally wanted was the "Christine" car (she wanted a car with fins). The Christine car was just way to large so I got her the next best thing:

View attachment 1715018788 View attachment 1715018790 View attachment 1715018791


The DC amp gauge was only $34 and I wish I had bought one 20 years ago. It takes all the guessing out of car wiring issues!!!
View attachment 1715018795

Treblig
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That is one Beautiful Studebaker!!!!!!!!!!!!!! Thank you for posting picture. I'm 71 and love all those 50's and 60's vintage.
 
I also have self resetting circuit breakers instead of fusable link.
They will shut the power down and then attempt to come back on, and if there is still a short they shut back off again.
I used the 30 amp size for through the bulkhead into the cabin, and it was about 4 bucks at Autozone.

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cudamike13 said:
That is one Beautiful Studebaker!!!!!!!!!!!!!! Thank you for posting picture. I'm 71 and love all those 50's and 60's vintage.
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Thanks for the compliment on the car, I'll be sure and tell my daughter. I bought the (slow blo) fuse holders at Pep Boys and made the brackets myself. I couldn't find my DC amp gauge earlier but finally tracked it down. I've used it many, many times in the last few months. I always wondered the difference in amperage draw (real life) between LED and regular car bulbs, with the DC amp meter it was easy to measure....BIG DIFFERENCE!!!. You get 10 times the light (lumens) for 1/5 the amperage!! When you drive a vintage car you want everyone to be sure and see those STOP lights when you hit the brake!!
I'm in my 60s so I feel the same about the older cars. I built a '46 Chevy Coupe for my son, he's been driving it for 6 years (started in high school) and he loves it very much. I told him that he can sell it and buy a new car if he wishes....he gets very angry every time I tell him to get a new car so I've stopped saying anything.

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Treblig
 
DesertRat said:
I installed a 40A circuit breaker in the line from my alternator to the battery and a 30A breaker from the battery to the inside of the dash. No fusable links anywhere in my car.
Click to expand...

What size alternator do you have? I want to do this exact setup but I have a 100 amp alternator and want to make sure I use the right size circuit breakers.
 
The Studebaker has a hundred amp alternator and so does the '46 Chevy. But without the amp meter there's almost no way to know how many amps your pulling. If you lived next door I'd lend it to you. The amp meter has many other uses for troubleshooting car wiring problems and can also be used for house current.

Treblig
 
kc0r8y said:
What size alternator do you have? I want to do this exact setup but I have a 100 amp alternator and want to make sure I use the right size circuit breakers.
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The output of your alternator is irrelevant to this issue. What matters is the connected load and unless you have a huge load of some sort, you want the breaker from the alternator to the battery to be sized small enough to protect the battery and the breaker from the battery to the interior controls of the car to match connected load. Things that effect connected load would be sound systems, amps, high power ignition systems. Caveat here, all this happens after the MAD wiring conversion!
Mine is basically stock so I opted for 40A from the alternator to the battery and 30A from the battery to the interior. Works well!
 
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DesertRat said:
The output of your alternator is irrelevant to this issue. What matters is the connected load and unless you have a huge load of some sort, you want the breaker from the alternator to the battery to be sized small enough to protect the battery and the breaker from the battery to the interior controls of the car to match connected load. Things that effect connected load would be sound systems, amps, high power ignition systems. Caveat here, all this happens after the MAD wiring conversion!
Mine is basically stock so I opted for 40A from the alternator to the battery and 30A from the battery to the interior. Works well!
Click to expand...

I actually have pretty much nothing that should be pulling a big load except for maybe the battery after a cumbersome cold start. I have line lock, a trans brake, and a couple small aftermarket gauges.

If the battery wears down some after a cumbersome (no choke) start, wont it ask for as much amperage as it can get to recharge?

Thanks for all your help guys.
 
DesertRat said:
The output of your alternator is irrelevant to this issue. What matters is the connected load and unless you have a huge load of some sort, you want the breaker from the alternator to the battery to be sized small enough to protect the battery and the breaker from the battery to the interior controls of the car to match connected load. Things that effect connected load would be sound systems, amps, high power ignition systems. Caveat here, all this happens after the MAD wiring conversion!
Mine is basically stock so I opted for 40A from the alternator to the battery and 30A from the battery to the interior. Works well!
Click to expand...


That's exactly what I have in the Studebaker. I have the battery in the trunk so I have one fuse between the alternator and the battery in case the alternator shorts out or in case the wire shorts out. Then using my amp meter, I determined how many amps the car (engine running with all accessories "on") main harness draws. Once I knew how many amps the engine and accessories draw I was able to determine what size fuse to use.

treblig
 
One caveat on those circuit breakers. They are affected by HEAT, not only current through the wire, but ENGINE heat. Be careful how and where you mount them.
 
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