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Alternator Upgrade Question

S

supersuby483

NAXJA Forum User
Location
clarksville
So as usual, I'm in the middle of a project and Murphy comes out. I want to know from anyone who has done an alternator and wiring upgrade, where and how did you connect the Alternator to PDC wire. I have a 95 4.0L AW4, and am trying to hook up a Durango alternator with 2 AWG wire.
http://www.flickr.com/photos/66919121@N05/6093596378/
6093596378

Still need to figure out which black with white strip wire it is.
 
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Approximately 10 years ago I upgraded the battery cables to 2 gauge fine stranded and charging cables to 4 gauge fine stranded.
Fabricated another stud for the PDC power and tied the battery into the original stud and the alternator into the fabricated stud and then installed a 125A 32V marine grade mini bus fuse across the studs to act as the fusible link.

standard.jpg


Several years ago the original alternator went bad (diode stopped functioning) and decided to upgrade to the 136A GC alternator.
At that time I upgraded the mini bus fuse to a 150A and the charging system has worked very well since then....
The installation of the alternator was a plug and play except for massaging the mounting brackets to fit the larger alternator case.
 
So an update to the picture. I can't figure out how to make this work. My thoughts right now are to cut the existing wire and splice it with the 2AWG wire. There will be a 150 amp mini-ANL fuse between the alternator and the PDC.

6093505303

http://www.flickr.com/photos/66919121@N05/6093505303/

If someone has a better idea please let me know. This is driving nuts and I am starting to think that maybe this is some knock off jeep made in eastern europe. :)
 
CharlesS solution is probably the ideal way to set this up but there is not room to do this on the '93 and I assume on the '95 (but don't know that for sure).

The cable from the alternator does not have to go to the PDC, it can go to a fuse mounted at a convenient spot such as the inner fender thence to the battery positive terminal. This setup is electrically equivalent to having the wire run to the PDC. 5-90 has some good info on this setup in his website: http://www.geocities.com/JeepI6Power/price.html
 
supersuby483 said:
So an update to the picture. I can't figure out how to make this work. My thoughts right now are to cut the existing wire and splice it with the 2AWG wire. There will be a 150 amp mini-ANL fuse between the alternator and the PDC.

6093505303

http://www.flickr.com/photos/66919121@N05/6093505303/

If someone has a better idea please let me know. This is driving nuts and I am starting to think that maybe this is some knock off jeep made in eastern europe. :)
Click to expand...

Take a picture from the top of the PDC showing how the battery cable and alternator cable attach to the studs on the PDC.
You should be able to install a fuse similar to the setup that I have pictured above.
If there is not enough room for some reason, then the idea that Pelican posted should work too....
 
6094310104

http://www.flickr.com/photos/66919121@N05/6094310104/

There is no cable that goes from the alternator to the battery. The only positive cables are Alternator to PDC, PDC to battery and Battery to starter.

I'm at a loss because the only input for power is in the bottom of the PDC, Black with white.

I'm really about to just put the old alternator back in and say hell with it.

I don't think there is any way to bypass the input in the bottom of the PDC.
 
I can only speak for my '93, but the A/C low side line leaves the compressor and extends directly across in front of the PDC. I've seen your installation in past threads and spent a lot of time trying to come up with a way to do do the same thing. The '95 may be completely different but thought I would mention the alternative solution just in case.

I'm not sure where I came up with the idea but I suspect it was from reading 5-90's site relating to battery cables. In any event, there is no reason for the OP to start cutting and splicing wires.

Beside the point, but we all may have gotten the idea from Craig Houghtaling's excellent write-up on the subject of replacement battery cables.
 
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I'm thinking about maybe running the alternator cable straight to the battery. Just still trying to figure why the alternator cable would go into the PDC with a 60 amp fuse.
 
I was composing while you posted but will go ahead and send this along.

You are missing the point here. The wire from the alternator does not have to go to the PDC. There is no reason whatsoever why this wire cannot go directly to the battery (through a fuse).

I suspect that the reason that the alternator output wire goes to the PDC is that the battery terminal already has two wires molded in and the third wire would make the terminal ungainly. Also need to have a place to mount the 60 amp fuses.

There are actually two 60 amp fuses for the alternator output: #1 and #9 on the '93.
 
supersuby483 said:
I'm thinking about maybe running the alternator cable straight to the battery. Just still trying to figure why the alternator cable would go into the PDC with a 60 amp fuse.
Click to expand...

Now that I have a picture of what your stock setup is... that explains a lot....
You can attach the new alternator cable to the front of the PDC at the battery connection point and install an inline fuse. Remove the 60A fuse from the PDC and safe off the old PDC alternator wire....
Donot install ONLY a 60A fuse.... The fuse should be roughly 150-175A.


Parts Express sells a variety of water proof fuse holders and fuses for different wire sizes.
Here are examples....

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=263-640
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=071-305
 
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CharlesS said:
Take a picture from the top of the PDC showing how the battery cable and alternator cable attach to the studs on the PDC.
You should be able to install a fuse similar to the setup that I have pictured above.
If there is not enough room for some reason, then the idea that Pelican posted should work too....
Click to expand...

That will work for the OBD-II PDC (M8 stud, 13m/m nut,) but would be difficult for the OBD-I PDC (M6 stud, 10m/m nut.) ANL and MEGA fuses both tend to require 5/16" or M8 studs in the first place - and the location of the studs is different (particularly if you have the double M6 stud.)

Also, the alternator output lead on the OBD-I PDC runs up into the bottom of the thing in the OEM configuration, rather than as a separate lead, and is fused inside the PDC.

If you have the OBD-I PDC, you're better off installing an auxiliary high-amp fuse holder (ANL, ANN, MEGA, even MANL) and running the alternator output lead to that - then running the other side of the fuse to either the stud on the PDC or to the battery + post (since they're constantly connected without switch or fuse between them, they're the same terminal - electrically speaking.)
 
Thank you all, this is very helpful. I already have a mini-ANL holder with 150 amp fuses, and tomorrow I will finish this up. I will let yall know what happens. Regardless of what happens should be something good. Jeep runs or bursts into flames (new Jeep). Only thing that bugs me is that I'm guessing now I just leave the old alternator output wire disconnected. 5-90, I do have the OBD-I system and will run the new alternator output wire to the battery with the mini-ANL 150 amp between them.
 
supersuby483 said:
Thank you all, this is very helpful. I already have a mini-ANL holder with 150 amp fuses, and tomorrow I will finish this up. I will let yall know what happens. Regardless of what happens should be something good. Jeep runs or bursts into flames (new Jeep). Only thing that bugs me is that I'm guessing now I just leave the old alternator output wire disconnected. 5-90, I do have the OBD-I system and will run the new alternator output wire to the battery with the mini-ANL 150 amp between them.
Click to expand...

For the OEM alternator lead, clip it flush with that silly moulded rubber block and coat the cut end with something like Plast-Dip to seal it. (You don't want corrosion to start inside that block. It's only there to "locate" all of the wiring, but it's not good to have corrosion going into something you can't see to inspect.)

At the PDC end, pull the two MAXI50 or MAXI60 fuses labelled "Generator" to isolate the other end of the lead - problem solved!

(You can probably cur the alternator end of that lead - on the other side of the moulded rubber block - and use it for a high-current auxiliary circuit, by replacing one of the MAXI fuses with whatever rating you'd need for the primary feed. I think MAXI fuses can be had 20-80A, in 10A steps.)
 
I did this upgrade to my 1999 XJ, by doing the following:

  • installing a resettable marine circuit breaker on the firewall). They come in various amp ratings - on EBay for $6-12 DELIVERED!
  • re-routed the upgraded #2 cable from the alternator to the breaker
  • installed a #2 from the breaker to the pdc stud
  • I removed the fuse @ the pdc & installed a large copper hex head grounding lug (http://www.elecdirect.com/product/3eda5ed2-a62a-4032-affe-2785a89c7d35.aspx)
I found a rebuilt high-output 180 AMP alternator on EBay for $150 with a 1 year warranty. Been a few months and it's running great. Highest output I measured was at 203 amps. It was being sold as an alternator for a WJ (1999-2004 Grand Cherokee).

All I had to do to get it to work in my 1999 XJ was to change the pully (the WJ pully has 7 grooves), ours only 6. The electrical connections were "plug-n-play."

I increased the size of all of the positive & negative cables to #2's while I was at it - including the starter cable. For an extra measure of security (in addition to crimping the terminals on the cable ends), I sweat soldered them & applied heat shrink tubing.

At the battery I changed the battery terminal connections to the O'Reilly/Kragens "Super Start Battery terminal" PN# 01412 - $6 each. They allow for easy in-field disconnection of a cable if needed, without destroying the fitting.
 
BarFlyFisherman said:
I did this upgrade to my 1999 XJ, by doing the following:

  • installing a resettable marine circuit breaker on the firewall). They come in various amp ratings - on EBay for $6-12 DELIVERED!
  • re-routed the upgraded #2 cable from the alternator to the breaker
  • installed a #2 from the breaker to the pdc stud
  • I removed the fuse @ the pdc & installed a large copper hex head grounding lug (http://www.elecdirect.com/product/3eda5ed2-a62a-4032-affe-2785a89c7d35.aspx)
I found a rebuilt high-output 180 AMP alternator on EBay for $150 with a 1 year warranty. Been a few months and it's running great. Highest output I measured was at 203 amps. It was being sold as an alternator for a WJ (1999-2004 Grand Cherokee).

All I had to do to get it to work in my 1999 XJ was to change the pully (the WJ pully has 7 grooves), ours only 6. The electrical connections were "plug-n-play."

I increased the size of all of the positive & negative cables to #2's while I was at it - including the starter cable. For an extra measure of security (in addition to crimping the terminals on the cable ends), I sweat soldered them & applied heat shrink tubing.

At the battery I changed the battery terminal connections to the O'Reilly/Kragens "Super Start Battery terminal" PN# 01412 - $6 each. They allow for easy in-field disconnection of a cable if needed, without destroying the fitting.
Click to expand...

Nice job - the only "mistake" is see was in swapping the pully. You don't have to - just put the belt on the back six grooves and call it good (leave the seventh - front - groove open and you'll be fine.)
 
5-90 said:
Nice job - the only "mistake" is see was in swapping the pully. You don't have to - just put the belt on the back six grooves and call it good (leave the seventh - front - groove open and you'll be fine.)
Click to expand...

Actually I would recommend swapping the pulley.
I agree that the additional groove for the belt doesnt affect the installation, but the pulley being larger in diameter will....
The XJ pulley is smaller than the ZJ pulley...
I suspect the belt tensioner can be adjusted to accomodate the larger pulley, but using the ZJ pulley will require that the engine spin faster to achieve the same load ratings....
 
CharlesS said:
Actually I would recommend swapping the pulley.
I agree that the additional groove for the belt doesnt affect the installation, but the pulley being larger in diameter will....
The XJ pulley is smaller than the ZJ pulley...
I suspect the belt tensioner can be adjusted to accomodate the larger pulley, but using the ZJ pulley will require that the engine spin faster to achieve the same load ratings....
Click to expand...

Hm. My usual advice is "don't bother" - and no trouble reported yet.

Just how do you swap the pully on an ND - it looks like it's pressed on, not retained with a nut like on the Delcos...
 
5-90 said:
Just how do you swap the pully on an ND - it looks like it's pressed on, not retained with a nut like on the Delcos...
Click to expand...


I used an air impact and just blipped the nut off and the pulley came off and then the reverse for installing....


standard.jpg



Sorry for the poor quality picture, but it is hard to fit a camera in front of the pulley while the alternator is installed.


Charles
 
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