Thanks. I don’t believe the indicator light ever came on since I’ve had it for three weeks.
The indicator light is the least important part of the system, and it’s only remotely related to the condition of the charging system. We’ll get to that last.
Thanks Mike- I’ll do that tomorrow - you’re a Godsend for your help. It’s a great car- this is the only thing wrong really.
I never liked that on my '68 the gauge is only telling the battery voltage rather than the system voltage. I routinely keep the battery on a trickle charger. I feel much more informed about what the alternator is doing when driving around since I got one of these to plug into the cigar lighter. Just a thought since they are so inexpensive. There are lots to choose from.
https://www.ebay.com/itm/193746834883?hash=item2d1c3615c3:g:ncAAAOSwOzld4NdY
David
68 E-type FHC
Not sure what you mean. The gauge shows the system voltage. If it reads something different than your plug-in, it’s just a calibration problem.
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No 12 v when car running at what I assume are the F1 n F2. The two terminals to right of red battery terminal. Zero. 12-14 at battery terminal.
It wouldn’t surprise me it’s the relay- it’s a mess:
I’m going to look at yr schematic on the relay n check for a short or on wrong terminal.
Here is what my '68 owners manual says about the gauge. I interpret this to mean that sometimes the battery gauge and plug in could read differently for a time without there being a calibration problem…
David
68 E-type FHC
Just curios do you know the color name of you’re car? Is it original? I am still trying to find the color name of my car, the closest I got was “Sand”,
which I think was a special order color.
The color is beautiful!
The wiring is terrible
Save yourself a fire and get a 1 wire
ALL of that goes away
Ps Mike if the dash bulb is burned out does that short the circuit on a 68?
Just asking….
Ascot fawn- you can get the info from Jaguar. Online paint Touchup wouldn’t even have it listed as a color. Hard to match-bring like I did the gas cap cover lid to computer generated match paint shop- make sure lid matches your color n shade of car.when I got my build sheet info it showed car had black interior- prior owner switched to the tan.
I couldn’t see color of wires to relay to match up to wiring diagram. Ones a ground. I did jump the relay alone n it did click. So maybe it was wired wrong?
Is there a GM 1 wire that’s a plug in? What model? Thx
I’d save my twin v belt pulley to put on. At this point I’m bringing it to the shop n get their input - I’d like to keep car as original as possible obviously but I want it to drive n not catch on fire more.
I don’t want to go above 70 amps- no ac or amplifiers
Chris these alts have been around for 40 years.
If your dealing with a shop, they can supply it.
You have to use your old pulley.
I thought moss motors started remaking the alt with the pulley.
If not ask sng or welsh, I think dave at welsh still has some around.
They are no more than 70 amp at max, I thought 65.
They bolt exact to the cradle, Run a 8 gage wire from the single post to the positive post and your done.
ALLLLLLL that other stuff just peel back till you find a nuclear physisist to fix 
Having fun with you, but its that easy.
Your mechanic should be able to do it
I just looked up their new version WOSP , internal regulator , 300 dollars new, Bolts right in…
Has options for dummy lights but in your case , one thing at a time…
Good luck.
pep boys 80 dollars
Having gone thru a couple alternators and voltage regulators in maybe 3 years, I switched to a modern alternator. 16 years ago.
Problem is that a failing alternator could damage the regulator so troubleshooting is a pita.
Line 3 is a good poetic hook
Lot’s of noise here. What you should do is first identify the wires on your relay, it’s very likely they’re just on the wrong terminals.
With the key off, test all four wires for 12v+. Put that one on terminal 30 on the relay.
With the key on, there should now be another wire powered. This can go to 85.
Key off now.
Next, set your meter to measure resistance (ohms). Disconnect both F wires at the alternator. Put one probe on the F+ terminal. Then put the probe on one of the remaining two relay wires. If the meter moves, then that wire goes to terminal 87.
The remaining terminal is a ground, and goes to 86.
To answer some of the above questions:
The light can’t make the alternator fail with a stock 11AC system. Period. Nor does the 3AW cause the alternator to fail (although the reverse is possible.) These are ancient myths.
A one wire GM alternator is perfect for your street rod. Don’t forget your Chevy crate motor while you’re at it.
Pascal, no fair, you have a V12 with a Butec (Leece-Nevile) system.
I think the problem here is that the relay wiring is confused. It’s likely that the only problem with it was the last mechanic. No need to reach for a wallet solution just yet.
Your owner’s manual is simply wrong. It’s a good thing that Lucas designed the electrical systems, and not Jaguar. The voltmeter senses power off fuse 7, which connects through the ignition switch to the positive distribution terminal behind the battery. The distribution terminal is the source of all system power, and ties the alternator and battery B+ terminals. It will reflect alternator voltage when the car is running, battery voltage when the engine is off and the key on. The lighter is powered from the same distribution post, through fuse 8. The “normal” band on your gauge goes from about 11.5V to about 14.5V. The needle is “central” on 13V, which actually isn’t normal for either the battery or the alternator. Go figure.
Um… why is it “silly?”
Many cars have had it for many years…?
Hi,
You could easily fry the wiring.
And with original components it’s ok, but with high output alternators always charge the battery before running the car. Allowing the alternator to charge a fully empty battery is asking for trouble. (Many folks have fried their alternators by doing that on a relatively modern Ferrari or Maserati.)
The original is pretty simple, could be a problem with a brush or a connection or the charging controller. Better check all of that first. On all my Jaguars the only one that needed to have an alternator replaced was the 3.2L MY1998 XJ8 after 15 years and 300.000+ kms (ca. 200.000 miles)
For rhe E-types or XJ6C it’s been either new brushes, fixing a connection of some wire (slip ring) or replacing a bearing, nothing else. YMMV.
Cheers!
I’m so good I didn’t even know I made a Funny!
“Save yourself a fire , Get a 1 Wire”!
That should be in the Lucas handbooks!
