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XJ6C charging issue, where to start on Diagnosis

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bmurphy7369

bmurphy7369

Jedi Trainee
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Hello All,
I have sold the XJ6C to a gentleman in California, I put a new battery in it and had the ignition wiring re-done and the auto-choke carbs set, very cold starting though and wondering a few things, mainly did the repair shop really set the choke properly? If not, how would anyone here recommend making cold starts less "pedal to the metal" revving for a 2 minute period until it warms up a bit. It runs perfectly when warmed up by the way.

Also, the battery is discharging pretty rapidly, it is reading on the low-end of the good range about 10-11 or so on the voltmeter on the dash, then if the headlights are turned on, it rapidly begins dropping to 9-8-7... within minutes. I am guessing that while it was in storage the alternator just gave out, but wondered if anyone could share the diagnostic trackdown for this issue...

Thanks for any advice on the two problems I'm having, I am transporting the car and it must be in good running shape/hassle-free for the transport company to even mess with the drop-off to us and save a grand rather than door to door which is at least a thousand more, and all they do is send a wrecker to pick it up and wench it up on the transport at the same place I could drive it too.... Go figure.
Best Regards to All, as Always,
Brian :cheers: :thirsty:
 
Battery voltage is 12.6V nominal on lead-acids, if I recall.

Your charging system is not functioning.
Newer alternators have the regulator built in.

If you have wires connected, and have power at the main wire (test light), pull the alternator and have it tested.

Belt is tight?
Not slipping?

When the car starts and you have to "rev it", are you getting black smoke out the tailpipe? (rich)
 
Alternator light on dash working? With key on, and engine not running does it light up? If NOT, replace that bulb with one of the others in the cluster and see if it charges. Daggone little lightbulb is a hard to find fuse.... Guess how I know this.
 
hmm.

My Lucas alternator has that little light.
Was (and is) charging fine, but for the first two months I had the car that light was burned out!
 
Brian, be sure you are getting battery voltage at the alternator with the engine NOT running and the ignition ON. This voltage at the alternator will be whatever the battery reads when tested at the battery. This way you insure your alternator field is actually getting the jump it needs to make electricity. ((You said ignition wiring, I assume ignition switch)) The alternator field gets it's power through the switch. No initial field voltage, no charge.
It's time to get out the VOM and start poking around. If you take your alternator to be tested, watch the idiot at autozone very carefully. They can fry a good alternator faster than you can shake a stick at it.

Since when is ANY jaguar ever started with pedal to the floor? Your choke isn't set up right.

good luck!
 
Thanks to all....

1) I did adjust the carbs myself, running better now, cold and warm, and I'm scared to touch the chokes at this point and the shop has really ticked me off.

2) The alternator light (I think my car has one, anyway) is not lighting up. The voltmeter starts out at around 10V, stays there until a good 1/2 hour or so of driving (lights on about 5-7 minutes!) then begins to drop out the "GOOD" zone. I thought yesterday it actually pushed up to 11V or better, but didn't last long.

3) The wiring work was actually the re-attachment of a slip of the hand, my poor work. It was all at the coil terminal wiring and ballast jumper, and it turned out that I was wiring it correctly after all, but the coil was dead, although it bench-tested perfectly for me and for the shop initially. They got that right, except.... I have a Crane XR-700 setup, ballasted, and the tach wire requires some modification if I understand correctly. I now have no tach, so maybe they didn't get it all right after all. If anyone knows what I am talking about with the aftermarket amp and the tachometer wiring, please chime in on this... it would be helpful for a better setting on the carbs.

4) The alternator could be on its way out, obviously, but the poor storage conditions this past winter (outdoors, wrapped on gravel at a shop that never got around to the car, due to illness, understandably in this case anyway), could have led to the old corrosion of terminals and wiring that I don't even know exist.

I will try all of the above, hopefully a bad ground wire to the battery??? Please say it's possible at least, I need a break here!

Thank you again to all, I'll test out the input you all have given, check myself in to the stress unit for a few days, and be back with a report!

Brian
:thirsty:
 
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