Previous Thread
Next Thread
Print Thread
Amp gauge bypass.....fusible link or not? #1845734
06/10/15 01:56 PM
06/10/15 01:56 PM
Joined: Oct 2011
Posts: 290
Dayton, WA
wesgtx440 Offline OP
enthusiast
wesgtx440  Offline OP
enthusiast

Joined: Oct 2011
Posts: 290
Dayton, WA
I am in the process of upgrading my 68 charger as per the MAD electric amp gauge bypass diagrams. I am going to install a 100 amp 1 wire alternator and perform the amp gauge bypass as well as run a larger charge wire from the alternator to the starter relay. My question is regarding the use of fusible links or is it better to install actual fuse holders in line? and what amp rating fuse or fusible link should be installed? Dash side wiring will be all stock with no additional draws on the system.


68 Charger R/T 440 auto
Re: Amp gauge bypass.....fusible link or not? [Re: wesgtx440] #1845761
06/10/15 02:44 PM
06/10/15 02:44 PM
Joined: Jun 2012
Posts: 1,386
Philadelphia PA
Pynzo Offline
Drugs are bad
Pynzo  Offline
Drugs are bad

Joined: Jun 2012
Posts: 1,386
Philadelphia PA
IIRC Mad recommend 5" of 14 gauge fusible link added to the end of a 10 gauge wire, from Alternator to starter relay.
Good info and a chart in this link:

http://www.allpar.com/history/mopar/electrical.html

Last edited by Pynzo; 06/10/15 04:31 PM.
Re: Amp gauge bypass.....fusible link or not? [Re: Pynzo] #1846255
06/10/15 10:41 PM
06/10/15 10:41 PM
Joined: Nov 2003
Posts: 36,039
Lincoln Nebraska
R
RapidRobert Offline
Circle Track
RapidRobert  Offline
Circle Track
R

Joined: Nov 2003
Posts: 36,039
Lincoln Nebraska
What Pynzo said, I believe they want 4 numbers (2 sizes) larger (which as you know is smaller gauge) as they only go up or down in even numbers so a 12 GA FL in an 8 GA wire is (2) sizes. I ain't up on electronics but I'd prefer a circuit breaker of the right type. I had a 66 dart that by itself overnight (diode in alt I believe) acted up & the wiring from alt to bulkhead & more/some on bulkhead to batt iirc was severely melted & the FL did not open


live every 24 hour block of time like it's your last day on earth
Re: Amp gauge bypass.....fusible link or not? [Re: RapidRobert] #1846349
06/11/15 12:38 AM
06/11/15 12:38 AM
Joined: Jan 2007
Posts: 7,664
IN
A
ahy Offline
master
ahy  Offline
master
A

Joined: Jan 2007
Posts: 7,664
IN
With a 100A alternator and output stud to fender relay wire, agree 8 gauge wire and a length of 12 gauge fusible link is good.

With a one wire, voltage drop in the charge wire is not compensated by remote sensing that ups alternator voltage to compensate... so the charge wire needs to handle typical current with minimal drop. If you have added non-stock accessories (eg fan, stereo, fuel pump, fans) that increase current draw, bigger wire is better. If electric load is increased, 6 gauge with 10 gauge fusible link would be better. I run this setup and has been trouble free.

AP stores rarely carry fusible link in 12 gauge or larger but "auto electric" stores generally carry at least 10 gauge.

NAPA also carries "maxi fuses" in high amperage ratings. If you use the fuse in place of fusible link, suggest at least a 125 A fuse with 100 A alternator. And get a spare for the glove box.

Re: Amp gauge bypass.....fusible link or not? [Re: ahy] #1847159
06/12/15 02:39 AM
06/12/15 02:39 AM
Joined: Oct 2011
Posts: 290
Dayton, WA
wesgtx440 Offline OP
enthusiast
wesgtx440  Offline OP
enthusiast

Joined: Oct 2011
Posts: 290
Dayton, WA
Thanks all for the helpful information. Looks like I have some wiring to do.


68 Charger R/T 440 auto
Re: Amp gauge bypass.....fusible link or not? [Re: wesgtx440] #1848052
06/13/15 01:32 PM
06/13/15 01:32 PM
Joined: Mar 2007
Posts: 3,274
West Coast, USA
jbc426 Offline
master
jbc426  Offline
master

Joined: Mar 2007
Posts: 3,274
West Coast, USA
You are doing yourself a dis-service by going with the one-wire alternator. Be sure the alternator you do use puts out a lot of amperage at idle. Most don't.


1970 Plymouth 'Cuda #'s 440-6(block in storage)currently 493" 6 pack, Shaker, 5 speed Passon, 4.10's
1968 Plymouth Barracuda Convertible 408 Magnum EFI with 4 speed automatic overdrive, 3800 stall lock-up converter and 4.30's (closest thing to an automatic 5 speed going)
Re: Amp gauge bypass.....fusible link or not? [Re: jbc426] #1848059
06/13/15 01:39 PM
06/13/15 01:39 PM
Joined: Nov 2003
Posts: 36,039
Lincoln Nebraska
R
RapidRobert Offline
Circle Track
RapidRobert  Offline
Circle Track
R

Joined: Nov 2003
Posts: 36,039
Lincoln Nebraska
I agree with JBC


live every 24 hour block of time like it's your last day on earth
Re: Amp gauge bypass.....fusible link or not? [Re: wesgtx440] #1848109
06/13/15 02:55 PM
06/13/15 02:55 PM
Joined: Dec 2003
Posts: 22,695
Bitopia
J
jcc Online content
If you can't dazzle em with diamonds..
jcc  Online Content
If you can't dazzle em with diamonds..
J

Joined: Dec 2003
Posts: 22,695
Bitopia
I am not sure I understand the real need for a fusible link where there was none. It does add a minor amount of resistance, and I thought there are reports of links opening with unpleasant results. There are a lot of cars that don't have this extra "safety" measure. I would think a true battery cutoff switch manual would be less headache and better in any full blown meltdown scenario. twocents


Reality check, that half the population is smarter then 50% of the people and it's a constantly contested fact.
Re: Amp gauge bypass.....fusible link or not? [Re: jcc] #1848114
06/13/15 03:05 PM
06/13/15 03:05 PM
Joined: Nov 2003
Posts: 36,039
Lincoln Nebraska
R
RapidRobert Offline
Circle Track
RapidRobert  Offline
Circle Track
R

Joined: Nov 2003
Posts: 36,039
Lincoln Nebraska
yeah that semi melted insulation on the firewall on my '66 dart was an eye opener for me & left a lasting impression (No mas ever again if I can prevent it). not sure what the solution is but its on my mind


live every 24 hour block of time like it's your last day on earth
Re: Amp gauge bypass.....fusible link or not? [Re: jcc] #1848120
06/13/15 03:13 PM
06/13/15 03:13 PM
Joined: Jun 2012
Posts: 1,386
Philadelphia PA
Pynzo Offline
Drugs are bad
Pynzo  Offline
Drugs are bad

Joined: Jun 2012
Posts: 1,386
Philadelphia PA
Originally Posted By jcc
I am not sure I understand the real need for a fusible link where there was none. It does add a minor amount of resistance, and I thought there are reports of links opening with unpleasant results. There are a lot of cars that don't have this extra "safety" measure. I would think a true battery cutoff switch manual would be less headache and better in any full blown meltdown scenario. twocents


I totally agree. I had bought and was ready to install a Fuse Link into my upgrade engine harness and decided against it. Ma Mopar didn't use it, why bother? You connect the Alternator output directly to the Starter Relay Stud, the Battery Cable hooks up here(unfused), and from here a 16 gauge fuse link feeds power to the dash harness.
Is there really a need to fuse the Alternator also?

Re: Amp gauge bypass.....fusible link or not? [Re: wesgtx440] #1848238
06/13/15 07:10 PM
06/13/15 07:10 PM
Joined: Apr 2015
Posts: 114
Oregon
W
Wagonman1967 Offline
member
Wagonman1967  Offline
member
W

Joined: Apr 2015
Posts: 114
Oregon
I had My 70 Charger fry the harness when the Alternator shorted. The Amp wire melted and shorted to a hot ign wire and the engine would not shut off.Now on My 68 R/R the harness is out for restore and that same ckt is melted. I have a new firewall plug coming and will modify,get rid of the Amp gauge ckt but leave the gauge in. I will use an aftermarket Volt meter.You would think MaMopar would of put a fuse link in there as a safety. Silly engineering if you think about it. Where is Ralph Nader when you need him. HA.


1968 Bronze Metalic Road Runner
!967 Malibu Wagon Original 4sd w/air
2001 Dodge Ram 4wd
1985 GMC K1500 4in lift
1993 Honda Civic W 350k Beater
2003 Honda VTX 1800 Bagger
Re: Amp gauge bypass.....fusible link or not? [Re: jcc] #1848262
06/13/15 08:21 PM
06/13/15 08:21 PM
Joined: Jan 2003
Posts: 25,591
Rio Linda, CA
John_Kunkel Offline
Too Many Posts
John_Kunkel  Offline
Too Many Posts

Joined: Jan 2003
Posts: 25,591
Rio Linda, CA
Originally Posted By jcc
I am not sure I understand the real need for a fusible link where there was none.


I don't understand the need for a fusible link even when there was one. A piece of wire that goes bad and doesn't always visibly show it= DUMB.

A fuse or breaker would be my choice.


The INTERNET, the MISinformation superhighway






Powered by UBB.threads™ PHP Forum Software 7.7.1