My Alternator is NOT Charging, I suspect Wiring...

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OK. Brief description of a HUGE Problem with my 1985 Jaguar: It is NOT CHarging the Battery, and failed EVERY Test given to it, with not a even a .01 Variance from Battery Output to what is measured int he Charging Test, Revved up or not.

AT LEAST 6 TIMES: -- Battery: "Good" (This is the one im trying NOT to "Cycle" too much)
-- Drain Test: PASS (.01A)
-- Charging: _NO VOLTAGE_
.. -EVERY TIME- Since i bought the CAR!!!

We Replaced the Alternator, with a Warranted Junkyard XJS Alternator. (It fit.) - Same Result.
Belt was Really REALLY Looose, i could spin Pulley in my Hand.. it is now Nice and Tight, cant move it with Hand at ALL.. Same result.

AC Compressor was removed.. Here is how it looks now http://i635.photobucket.com/albums/uu72/jcorbi82/100_2712.jpg

WHERE DO I GO FROM HERE?

I do NOT see the "Battery" Light on the Dash.. but i discovered this morning that it DOESNT come on when i turn the key.. only Coolant Level Light, Seatbelt Light, and Oil Pressure Light.

Sooo.. i suspect Wiring, SOMEWHERE.. Possible AC Compressor (Removed because it was Seized and originally had NO Belt on Alternator) connections to Alt, or other Wiring WRONG?

Im tempted to pay the $60 for "Electrical Diagnosis," as the one shop said i MAY just need $40 of "New Wires".. as the Alternator MAY be Fine!

I do not Trust Advance, all they can say is "The Charging test shows its not charging, so you need an Alternator." Did that already..

Advice? Thoughts? Should i take it for the Electrical Diagnostic, they said theyd credit the cost of Diagnosis to the repair IF it was Alternator, if its wires that may solve my Problem too?
 
Does this use an internal or external voltage regulator?
A very easy check to see if the alternator is producing current is to touch be rear bearing cap with a screwdriver when its running,it should pull it to it with magnetic force.Not very scientific and will not tell how much is being produced but it works enough to tell if the thing is functional and the field and armature are not shorted.
 
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you can take the alternator off and have it tested at a parts store. That would for sure give you a go/no go for the alt. If it is good, then your down to tracing wires and/or testing wire continuity.
 
Originally Posted By: Trav
Does this use an internal or external voltage regulator?


Didn't even think about the possibility of it using a external voltage regulator. If the regulator is toast that could cause your problems.

maybe someone could chime in if there is a way to test it with a multimeter? Or maybe you can take it off (assuming it has one) and have a parts store test it.
 
Depending on the alternator it looks like it could have an external.These are electronic and non repairable,good old Lucas electrics.

If you feel magnetic pull on the rear bearing the regulator is probably working if not you need to jump the regulator wires with a test cable and clips and retest.If it has magnetic pull now the regulator is bad if not then you can bet on the alternator.

This is real backyard stuff but it works well enough to isolate the component.Google may help but chances are you wont find much for this one though.I have a feeling this is an expensive regulator new so a used one is possibly the way to go if needed.
 
Originally Posted By: Bluestream
I recommend you post your question here:

http://forums.jag-lovers.org/index.php3

Go right to the veterans..


.. Did already! I am jcorbi82 on there... Some nice people there even sent me a Haynes Manual and Owners Guide!! .. amd i STILL cant figure it out!

frown.gif


Addyguy:
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lol
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Well.. let me see if i left anything out... Oh yes: Does anyone know where the Regulator would BE on my car? Its a 1985 XJ6 4.2 ...

This is my Third post, and i gave my word, so ill look at the Replies until Tomorrow. Thanks!

About to drive Downtown on battery Only.. Again..
frown.gif


P.S.: HOW do i make the DASHBOARD light that shows the Battery come on at IGNITION!? That may be my whoel problem...

Notice that in that mess of Wires, the Battery Ligth on the dash doesnt come on AT ALL.. i checked thsi morning, so it was suggested the Alternator will never "Start" Charghing. is there a way to Remedy this? - Wire or Fuse? .. Involved, or Not Involved?

100_2712.jpg
JAG2.jpg
 
There is always a way to bypass or rewire the thing so that it will charge. But w/o a wiring diagram and a good understanding of how Lucas thinks and builds stuff your just spinning your wheels.
 
The regulator maybe on the firewall or fenderwell.Unless your good with wiring Lucas electrics are not what i would call a good place to get a little OJT.They have some nasty habits like catching fire and so on,take it to an automotive electrician.

Lucas: Inventor of the three position switch. But what are the three positions?

•Dim, Dimmer, Off (Lucas Headlight Switch)

•Slow, Slower, Stopped just in your field of view (Lucas Wiper Switch)

•Smoke, Smoulder, Burn (Lucas General Purpose Switch)
 
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Advice? Thoughts? Should i take it for the Electrical Diagnostic, they said theyd credit the cost of Diagnosis to the repair IF it was Alternator, if its wires that may solve my Problem too?


I've had a lot of Jaguars, and still have two, and I've never seen one with a bad alternator, even out to the 250K range. I've also never seen "bad" wiring. I've seen connectors and grounds gunked up and oxidized that need a good cleaning, but that's about it.

The only charging issues I ever had or heard of were physical wear on the brushes. All of mine were Xj40 series or later, but the brushes are easily replacable, can be obtained at any decent hardware store, and reside in a carrier that can be removed from the alternator with one screw.

Early Xj40's also had what is called a load dump module, that would enable the charging system. I don't know if Series III cars have that "feature" but if it does, make sure it is connected up and well grounded.

Jaguars are durable and very easy to work on cars, unless a hack or an idiot "mechanic" got there before you. People unfamiliar with the British way in general, and Jaguar way in particular, can inflict a lot of expensive damage, and fast. Any place that does not have experience with British cars will probably further damage your car in the process of attempting to repair it. And then they will try to charge you for it.

There should be a user developed service manual for the Series III on Jag Lovers. There are for the later models.

Congrats on the Series III; I have always wanted one of those and an XKE, but I'm out of room for cars right now - I would need to build another shop building or expand the one I have.
 
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Originally Posted By: Trav

Lucas: Inventor of the three position switch. But what are the three positions?

•Dim, Dimmer, Off (Lucas Headlight Switch)

•Slow, Slower, Stopped just in your field of view (Lucas Wiper Switch)

•Smoke, Smoulder, Burn (Lucas General Purpose Switch)


Trav,

You have evoked the name Lucas; aka "the prince of darkness"
 
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Have the alternator tested off of the car. This should be free or a nominal charge.
This is your first step.
But for a quick test, there are wires, fuses, and fusible links [wires that are fuses and melt internally] that can be checked.
 
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