NAXJA Forums -::- North American XJ Association  

Go Back   NAXJA Forums -::- North American XJ Association > NAXJA Other Technical Forums > Jeep CJs and Wranglers > Wrangler JK and JL (2007 - Present)
HOME Member FAQ Sponsor Info Rules Bylaws E-Mail

Wrangler JK and JL (2007 - Present) Technical forum for new-generation Jeep Wrangers.

Reply
 
Thread Tools Rate Thread Display Modes
  #16  
Old July 20th, 2017, 06:56
SBpunk SBpunk is offline
NAXJA Forum User
 
Join Date: Jan 2013
Location: Enid, OK
Posts: 339
Re: upgrading alternator wiring

Nevermind looks like photobucket has gone to complete crap.
Reply With Quote
  #17  
Old July 20th, 2017, 08:31
Anak's Avatar
Anak Anak is offline
Stranger
 
Join Date: Sep 2013
Location: In a strange land
Posts: 3,340
Re: upgrading alternator wiring

If you have an HO PDC you can add a fuse at the end of it.

Components, the way I did it:





Assembled:






Somewhere around here is a picture of everything in place, but I can't seem to find it at the moment.

I would ditch the fusible link. Those things just bug me. It is far easier to test a fuse for continuity and far easier to replace it should the need arise.

ETA: Check out this thread for ideas: http://www.naxja.org/forum/showthread.php?t=1114880
__________________
Project "Scope Creep": 1996 4wd 4.0L, AX15
....

Baby it's cold outside.

Last edited by Anak; July 20th, 2017 at 08:35. Reason: Mo' info
Reply With Quote
  #18  
Old July 20th, 2017, 09:59
donthelegend donthelegend is offline
NAXJA Member
 
Join Date: Apr 2010
Location: St. Louis, MO
Posts: 388
Re: upgrading alternator wiring

Quote:
Originally Posted by Jeep Driver View Post
This has nothing to do with draw, has to do with output.

If you have a 160amp alt, it WILL put out 160 amps.

You are protecting the entire electrical system from the alt........again, nothing to do with draw.

No, I would not use, did not use, a breaker.
Quote:
Originally Posted by Jeep Driver View Post
You need to be beyond your amp output...............175 at least, if not 200.
Quote:
Originally Posted by Jeep Driver View Post
If you use a 150amp breaker with a 160amp alt, you will be constantly resetting the breaker
This is pretty much all incorrect.

1.Alternators aren't constantly putting out max current. They aren't putting out any more current than is being drawn by the system they're attached to. It has EVERYTHING to do with draw.

2. A 160 Amp alternator will only put out 160 amps under certain conditions, namely, when turning fast enough to produce that much current, and when there is that much current being drawn by the battery, engine, lights, radio, and whatever else is using power in the system.

3. Because of 2, if you don't ever need more than 150 amps, there's nothing wrong with 150 amp breaker/fuse on a 160 amp alt. The breaker/fuse is there to protect your wiring first.

4. Nothing wrong with the breakers instead of fuses, I run a 125 amp breaker in my daily driver XJ with stock alt. I run a 150 amp ANL fuse in my trail rig with a 160 amp alternator. Have never popped the breaker or fuse. Installed 125 amp breaker in two other XJs with stock alternator output without problems. All with 4 gauge cables I made.


To the OP:
Get rid of the fusible link/stock alternator positive wire entirely. Replace with 4 gauge or larger wire, with either a fuse or breaker sized to protect the wire or to match the output of the alternator, whichever is smaller. (IE: 0 gauge wire will handle more power than a 136 amp alternator will ever produce, so i'd suggest a 150 amp fuse/breaker which is probably the closest to 136 you'll get without being under sized). Alternatively, if you don't ever need the extra power, you'd probably be fine with a 125 amp breaker, but there's no real reason to undersize the breaker since the wire will handle the extra current without a problem.
Reply With Quote
  #19  
Old July 20th, 2017, 10:38
RCP Phx RCP Phx is online now
NAXJA Forum User
 
Join Date: Mar 2003
Location: Phoenix,Az
Posts: 12,890
Re: upgrading alternator wiring

^^^^^^This is correct, I don't know of a better way to explain it! Jeep Driver lives in a world of his own!
Reply With Quote
  #20  
Old July 20th, 2017, 10:47
Kejtar's Avatar
Kejtar Kejtar is offline
PostMaster General
 
Join Date: May 2002
Location: Westminster, SoCal
Posts: 18,513
Re: upgrading alternator wiring

thanks guys! I was starting to doubt myself but what helped me hold onto my sanity is the fact that the stock skinny wire is not burning up and it definitely does not handle 160 amps....

I'll look into getting rid of the stock wire, but I want to make sure that there is not a connection going someplace in the loom between the alternator and the battery that I'm overlooking. That's the main problem - loom is buried - and ..... gasp..... it's not an XJ that we're talking about And I don't have an FSM for this rig...
Reply With Quote
  #21  
Old July 20th, 2017, 11:00
Sean778's Avatar
Sean778 Sean778 is offline
NAXJA Member
 
Join Date: Dec 2006
Location: Edmonton
Posts: 29
Re: upgrading alternator wiring

My experience with using a breaker to replace a fusible link on my XJ left me stranded on more than one occasion. I upgraded my battery cables to 4 gauge welding cable, and installed a higher output alternator at the same time. My alternator was rated at 144 amps, and I used a 140 amp breaker. I had no indication in the cab when it would trip, and the rare time that it did trip it would run fine until I had no juice left in the battery. I have since switched it out for a 150 amp ANL fuse and had no problems.
Reply With Quote
  #22  
Old July 20th, 2017, 11:38
donthelegend donthelegend is offline
NAXJA Member
 
Join Date: Apr 2010
Location: St. Louis, MO
Posts: 388
Re: upgrading alternator wiring

Quote:
Originally Posted by Sean778 View Post
My experience with using a breaker to replace a fusible link on my XJ left me stranded on more than one occasion. I upgraded my battery cables to 4 gauge welding cable, and installed a higher output alternator at the same time. My alternator was rated at 144 amps, and I used a 140 amp breaker. I had no indication in the cab when it would trip, and the rare time that it did trip it would run fine until I had no juice left in the battery. I have since switched it out for a 150 amp ANL fuse and had no problems.
Obviously you actually use the full output your alternator is capable of, I don't think that has anything to do with the fuse vs breaker argument, except that fuses are generally available in smaller increments. Increasing the amperage is what fixed your problem, not going to a fuse. (Slow blow fuses may give a bit more leeway than the same size breaker but ultimately it comes down to sizing everything correctly for whatever components you want to use).

Blowing the fuse isn't going to give you any more indication while driving than the breaker did, but now you better have an extra fuse or you're stranded. The breaker can be reset in less than 30 seconds and assuming there's not an actual short, you're good to go.
Reply With Quote
  #23  
Old July 20th, 2017, 12:00
Kejtar's Avatar
Kejtar Kejtar is offline
PostMaster General
 
Join Date: May 2002
Location: Westminster, SoCal
Posts: 18,513
Re: upgrading alternator wiring

So scratching my head thinking about this - I could wire up an "alarm" indicator of sorts that would trigger if a voltage drops below a certain level. I do have a gauge that gives me current voltage but I don't keep looking at it the whole time as it's off to the right on the center console.
Reply With Quote
  #24  
Old July 20th, 2017, 12:47
ehall's Avatar
ehall ehall is offline
NAXJA Member
 
Join Date: Dec 2007
Location: Southern Maryland
Posts: 9,298
Re: upgrading alternator wiring

Quote:
Originally Posted by XJwonders View Post
I would trust megafuse over anl fuse. Those anl fuseholders Re a joke compared to a mega fuse holders.
The ANL holders are junky but its much easier to visually inspect an ANL fuse and they come in much higher ratings than the Mega fuses
__________________
.
my '91 beater rebuild
Reply With Quote
  #25  
Old July 20th, 2017, 13:15
Green XJ Jeep Green XJ Jeep is offline
NAXJA Member 4950
 
Join Date: Mar 2011
Location: Spanaway Wa
Posts: 560
Re: upgrading alternator wiring

Quote:
Originally Posted by Jeep Driver View Post
You need to be beyond your amp output...............175 at least, if not 200.

Megafuses are $5
If you are going to go that far over the rated output then there is no need for any forn of circuit protection.
Reply With Quote
  #26  
Old July 20th, 2017, 13:50
donthelegend donthelegend is offline
NAXJA Member
 
Join Date: Apr 2010
Location: St. Louis, MO
Posts: 388
Re: upgrading alternator wiring

Quote:
Originally Posted by ehall View Post
The ANL holders are junky but its much easier to visually inspect an ANL fuse and they come in much higher ratings than the Mega fuses
While you're not wrong, mega fuses are available up to 500 amps so they shouldn't exactly be a limiting factor for the charging systems people on this site are using.

They're also a third of the price compared to ANL fuses of the same rating
Reply With Quote
  #27  
Old July 20th, 2017, 18:39
Heavyopp Heavyopp is offline
NAXJA Member
 
Join Date: Jan 2017
Location: Middlesex, NJ
Posts: 826
Re: upgrading alternator wiring

So I get that a 160 amp alternator only puts out 160 if the demand is there -- my question is what fuse would you use as the main?

If your wire is big enough are we really just protecting agains a dead short?

That would mean a 175 mega for a potential 160 amp draw

Am I thinking right?
Reply With Quote
  #28  
Old July 20th, 2017, 19:03
Jeep Driver Jeep Driver is offline
NAXJA Forum User
 
Join Date: Jun 2016
Location: Parrottsville
Posts: 697
Re: upgrading alternator wiring

Quote:
Originally Posted by donthelegend View Post
This is pretty much all incorrect.

1.Alternators aren't constantly putting out max current. They aren't putting out any more current than is being drawn by the system they're attached to. It has EVERYTHING to do with draw.

2. A 160 Amp alternator will only put out 160 amps under certain conditions, namely, when turning fast enough to produce that much current, and when there is that much current being drawn by the battery, engine, lights, radio, and whatever else is using power in the system.

3. Because of 2, if you don't ever need more than 150 amps, there's nothing wrong with 150 amp breaker/fuse on a 160 amp alt. The breaker/fuse is there to protect your wiring first.

4. Nothing wrong with the breakers instead of fuses, I run a 125 amp breaker in my daily driver XJ with stock alt. I run a 150 amp ANL fuse in my trail rig with a 160 amp alternator. Have never popped the breaker or fuse. Installed 125 amp breaker in two other XJs with stock alternator output without problems. All with 4 gauge cables I made.


To the OP:
Get rid of the fusible link/stock alternator positive wire entirely. Replace with 4 gauge or larger wire, with either a fuse or breaker sized to protect the wire or to match the output of the alternator, whichever is smaller. (IE: 0 gauge wire will handle more power than a 136 amp alternator will ever produce, so i'd suggest a 150 amp fuse/breaker which is probably the closest to 136 you'll get without being under sized). Alternatively, if you don't ever need the extra power, you'd probably be fine with a 125 amp breaker, but there's no real reason to undersize the breaker since the wire will handle the extra current without a problem.


There is nothing there that I said that was wrong or incorrect.


He will not be fine with 125 amp breaker.


There is plenty of scenarios in which he will be a full load, or that the alt will sense a full load.

Cruising the back roads at night with AC, aux lights, Efan, head unit with amp......etc.........

Jump starting another vehicle.

Or any thing else that will drain the battery...........like running a wench.

Mine puts out 100amps at idle..........not 5amps here and 30amps there.........100amps.

Reply With Quote
  #29  
Old July 20th, 2017, 19:04
Jeep Driver Jeep Driver is offline
NAXJA Forum User
 
Join Date: Jun 2016
Location: Parrottsville
Posts: 697
Re: upgrading alternator wiring

Quote:
Originally Posted by Heavyopp View Post
So I get that a 160 amp alternator only puts out 160 if the demand is there -- my question is what fuse would you use as the main?

If your wire is big enough are we really just protecting agains a dead short?

That would mean a 175 mega for a potential 160 amp draw

Am I thinking right?
That's correct.
Reply With Quote
  #30  
Old July 20th, 2017, 19:05
Jeep Driver Jeep Driver is offline
NAXJA Forum User
 
Join Date: Jun 2016
Location: Parrottsville
Posts: 697
Re: upgrading alternator wiring

Quote:
Originally Posted by Sean778 View Post
My experience with using a breaker to replace a fusible link on my XJ left me stranded on more than one occasion. I upgraded my battery cables to 4 gauge welding cable, and installed a higher output alternator at the same time. My alternator was rated at 144 amps, and I used a 140 amp breaker. I had no indication in the cab when it would trip, and the rare time that it did trip it would run fine until I had no juice left in the battery. I have since switched it out for a 150 amp ANL fuse and had no problems.
Thank you for making my case.
Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Upgrading the alternator.... Senior_XJ Modified Tech Discussion 3 September 7th, 2008 23:15
Upgrading an alternator? Double Down Modified Tech Discussion 41 March 27th, 2008 18:23
Higher Amp Alternator Upgrading ihscoutlover Modified Tech Discussion 0 January 16th, 2008 19:02
Upgrading Alternator - Which One? Spidey Modified Tech Discussion 6 January 20th, 2005 15:19
Upgrading the Alternator wilson0309 Modified Tech Discussion 18 October 21st, 2003 08:36


All times are GMT -7. The time now is 12:09.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
NAXJA and NAXJA logo's Copyright NAXJA. All content/images Copyright NAXJA 1999-2014