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'99 4.0L Alternator

HokieXJ

NAXJA Forum User
Location
Blacksburg, VA
I seem to be able to find lots of information and parts for 90-98 alternators.

I'm curious if the 99 XJ 4.0 alternator is anything special or if one of the others will fit right in (both mechanically and electrically)?
 
As I recall, it's much the same ND unit that Chrysler used otherwise, although the rear housing may be "clocked" differently.

If you want an upgrade, you can think about a Durango alternator or a later WJ alternator (which should net you ~130A, if it works) or you can order one from Rod - which will be cheaper than Mean Green. Click the link in my sig, go to "San Jose Generator," and see what you think.
 
5-90 said:
As I recall, it's much the same ND unit that Chrysler used otherwise, although the rear housing may be "clocked" differently.

If you want an upgrade, you can think about a Durango alternator or a later WJ alternator (which should net you ~130A, if it works) or you can order one from Rod - which will be cheaper than Mean Green. Click the link in my sig, go to "San Jose Generator," and see what you think.
You'll have to explain to me what clocked means. I have noticed that I have a two wire connector on the back of mine that appears to be absent in other Jeep alternators. This is the regulator connection probably?

San Jose Generator rewinds one to 130A for $125? Is there a core charge as well? Do they go above 130A?

Thanks for the help while I'm figuring this out.
 
99 is the year Jeep upgraded to the 120 amp alternator it would utilize in the 99, 2000, 2001. If you go with a 90-98 you will be buying a 90 amp alternator (downgrading) unless you buy and upgraded unit (mean green or other). Take a look at an online parts store and you will see 99 is the first with the 120 amp alternator.
 
HokieXJ said:
You'll have to explain to me what clocked means. I have noticed that I have a two wire connector on the back of mine that appears to be absent in other Jeep alternators. This is the regulator connection probably?

San Jose Generator rewinds one to 130A for $125? Is there a core charge as well? Do they go above 130A?

Thanks for the help while I'm figuring this out.

"Clocking" is more commonly used when referring to Delco alternators - particularly the old Delco SI units (early internally-regulated units, with the two-wire regulator connection.)

The Delco SI's were available in four "clocks" - three, six, nine, and twelve. This referred to the location of the regulator connection, looking at the back of the unit, with the large mounting bolt lug (the pivot) at the bottom and the adjuster screw tab at the top. There were four case screws, and they were evenly spaced. You'd "re-clock" the alternator in order to make sure that there wouldn't be mechanical interference with the regulator connection (read: you didn't want something metal to hit the MOLEX plug.)

Since most alternators use either three our four evenly-spaced screws to hold the front and rear case halves together, most alternators can be "re-clocked" easily. Mainly, you're just changing the location of the connections on the back/side relative to the mounting screws.

Rod hasn't mentioned a core charge (I've not had to deal with one, but I usually just take the old unit in and pick it back up an hour or so later...) and I've not had to put one on the website. Either way, I'm sure he'd appreciate getting your core back - to keep his stock of cores up. Easiest to address that with him, since you'd need to deal with him directly (I built the pages for him, but I don't "middleman" for him - I'm trying to save everyone a few bucks here...)

As far as increasing the capacity - please be sure to ask him when you call. It took me a bit to talk him into doing mail-order in the first place, but he's done fairly well with it. Doing that was a first step tho - I'd like to see about getting him to offer high-amp units, and having people ask him when they call in orders would be a lot more effective than me pestering him in person (if I do it, it's just me. If you all do it, there are more people involved.) When I talked him into doing this for us, I had two goals in mind:
1) Save a few bucks over most of the mail-order people, while still offering quality parts.
2) Expand him into a "high output" direction, and give the "high-amp" houses a bit of competition. I won't be able to talk him into doing "weldernators" (so please don't ask - there's just too much abuse on units used to power welding directly,) but I'd like to see him do a little more high-amp stuff than he's been doing so far.

But a key advantage in dealing with Rod is that you talk to the guy who runs the shop, does the building, and does the testing. His test bench may look like something out of Frankestein (I swear, a Jacob's Ladder wouldn't be out of place on top of the thing...) but it will wring an alternator, a generator, or a starter right out and tell him just what's wrong with it - be it low current (yes, he tests at full output,) diode ripple, a blown regulator, or whatever. There's a reason I've been dealing with him for 10 years - and that reason is that his parts have been truly "install and forget." The only time I need a new starter/alternator from him is when I buy another rig, or when I'm working on someone else's gear. That's worth a lot to me...

He does keep banker's hours tho - and here on the West Coast. I've been meaning to talk him into an email address to go with the website I've got up for him - that would make it easier for you guys out East to deal with him, since you don't have to be sure to ring him by two...
 
cklaus said:
99 is the year Jeep upgraded to the 120 amp alternator it would utilize in the 99, 2000, 2001. If you go with a 90-98 you will be buying a 90 amp alternator (downgrading) unless you buy and upgraded unit (mean green or other). Take a look at an online parts store and you will see 99 is the first with the 120 amp alternator.

Most parts places have the 90A as std and the 117A as optional listed for the '99. I really am not sure what it is without taking it off. I tried looking for a plate in every direction I could, but I didn't see any identifying marks.
 
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