Not sure whats going on but my battery light on the dash wont go away. Just had the alternator and volt regulator replaced. The battery is only about a year or 2 old and driving performance doesn't seem affected. Could it just be a terminal to the battery? The volts on the meter always read the right readings. Sometimes in the morning though I notice it will be about 14-15 volts. Later in the day it goes back down and stays around 13

 

Those voltages seem OK. I'm not an expert of the Lucas charging system, but on these older cars, it pays to clean all the connections as corrosion can cause voltage drops and fools the system into showing a warning light.

Is your battery earth cable connection nice and clean where it bolts to the bodyshell ?

 

you need to trace the problem to the newly rebuilt alternator / voltage regulator.
perhaps the connections?

who did the work?

 

Ok i will check and get a wire brush, i had a shop do the job. Battery was overcharging and in the red zone every time i accelerated.

 

A charging voltage across the battery terminals while the engine is running between 13.5 and 14.5 volts is normal and expected. Anything outside this range would need investigating.

 

at this point I would get a new alternator, the car is worth it, if you can bite the bullet.

get the Bosch for the XJ-12, more juice, it mounts the same way.

Doug knows the part number and where to get it.

 

Another option is to get the alternator mount kit from John's car and put in a run-of-the-mill delco alternator. Mine lasted over 100k miles even though it was soaked in oil (engine is out currently for a rebuilt). Replace it once and you are done!

 

I did John's Cars Gmalt conversion in my car and I was dissapointed, first time I hear of someone else doing it. I even purchased the NEW alternator from John's Cars.

but the Delco alternator seemed weak compared to the original Lucas, and the gauge became very slow to rise to 13V. Also when the a/c is on, and the parking lights are on, engine running, the voltage shown at the gauge goes down to around 9V, when the Lucas kept a steady 13V at the gauge.

I have purchased other mods from Jon's Cars which are excellent improvements, but the GMalt I did not like one bit.

 

Jose:


Could it be:


1. The Jaguar voltage "indicators" are only that and a tad slow to react anyway.
2. John's kit is fine, but the GM alternator is bad or the wrong choice.


If the AC keeps going, the lights stay on and the car will start up, what is wrong?


I made a patch cored for my HF VOM. I can connect it via the cigar outlet. Now, I can read when I so choose, volts under various loads and RPM's in real time.


Not to demean "good" Lucas or Bosche alternator. Poorly rebuilt units come in all specie.


The best thing as to the Delco's is that any decent parts house, anywhere will have one. Not so much witht he Lucas or bosch???


And, some new Asian replacements seem to be lacking as well.


I have a new starter for my LT1. Made in Malasyia. I hope for the best. On the
bench now, old one as well. Can't tell if the old one is GM or also a replacement of some kind. They are almost, but not quite alike.


Carl

 

Carl,
I think either Number 2 or that's the way GM alternators are. With so many GM parts in these Series 3 XJ, I also wonder why Jaguar went with the Lucas instead of the GM.

As soon as I replaced the Lucas (original) alternator, the problem went away, the Lucas is what I have installed, so far so good, but I want to try the Bosch for the XJ-12.

 

I've no stock in GM. wish I did!!


There are a lot of Delcos of various configurations and outputs. Not to mention pulley size. The matchup is what I was referring to. Capacity vs load and at what RPM.


The other is that the Delco was flawed. a poor rebuild?


Delco alternators made their appearance in about 1964. My 63 Corvair had a generator, probably by Delco, but the 65 Corvair had an alternator by Delco. a tad different to accommodate the engine'sCCW rotation!!


So, how many millions have found their way out to the road, and functioned well???


My LT1 has a a really big 140 amp Delco. Mounted topside. but, I hope I don't need to replace it.


Our 71 AMC Hornet aka Rambler ohv six had a Motorola. it did just fine, albeit the car was minimaly equipped with electricity eating gadgets. AC, windows, door locks, etc.


My 94 Jeep Grand Cherokee has a descendant of that really good engine.


Carl

 

the pulley matched the pulley in my Lucas, so that was not an issue. The alternator was purchased new, unless John stung me with a reman, but I doubt it, I can tell a reman from new. I've never had it checked, I just removed it and re-installed the Lucas.

note that I did not replace the Lucas because it was bad, only because I thought the GM had more juice for the osterizer, fax machine, garbage disposer, hair dryer, George Foreman Sandwich maker, and other neccessities, but that did not work out.

tell you what, replacing alternators in the XJ-6 is a job I don't look forward to, but no matter how painful it is, I prefer to do it myself because I do it right.

 

Somewhere I saw a chart for outputs at various RPM's by various Delco units.


But, why was it not Ok, no matter what the "indicator" read f all functioned??


You need a trailer with a generator to power all those gizmos.


But, now you have either kit for sale or a back up if the Lucas packs in.


But, all is well that ends well.


My DIY days are shrinking. If I ever get that starter in, I'll not look forward to an under the car job. Once upon a time, no big deal....


Carl

 

Some Jaguars had Ducellier alternators.

Just throwing that in.

 

I've heard of that brand, never seen one.

 

French outfit?


I seen mention of ignition coils by them for Jaguars.


Pronunciation???


That language thing.


Carl

 

Jaguar like many other makers outsourced so much.

 

Italian I think

 

No, it was a French company, it was purchased by Valeo, a French brake and clutch company, in 1984.

 

I checked all the connections and everything looked good. I went to oreillys for a alternator test and the results came back good. But I had a battery test and it was saying bad battery. I took it to a buddy of mine and his load test came out good on the battery. Must just be the dummy light. After driving lately I do notice while going the volts stay around 13 instead of 14 where they should be. Battery is a interstate and is about a year and a half old