Hello everyone,

The alternator on my XJR gave out (the pulley will not spin anymore and the alternator belt gave out because of that). Instead of buying a used or rebuilt one, I would like to rebuild it myself.

Does anyone know where to purchase alternator repair kits? And what should I look for when purchasing a repair kit? I can't even tell who the alternator manufacturer was from looking at it...

And what are the specifications for this alternator? i.e. voltage and current requirements etc

All help is appreciated

It is a Denso alternator, but I dont know the denso part number. From memory, it is on a label on the alternator, which can be seen without removing the alternator. Denso do sell refurb kits, and there are even some you tube videos showing you how to do it.
Removing the alternator from the car is a lot of fun, and there is a how to guide on here somewhere, which you would be well advised to read!

You were right, there is a tag on the alternator except on mine it is damaged and I can't look up the Denso part number.

Anyone know what that would be?

Here is a link to the Denso site fora reman altenator for an XJ6 they don't list one for the XJR not sure if they are the same but I would think so. Didn't notice anthing about rebuild kits but you could probably call them.

Find My Part | DENSO Auto Parts

Google is definitely your friend here. Try googling denso rebuild
Kits, and go from there. I'm sure they list model applicability.

I think I got the relevant part numbers from this eBay listing:

New Alternator Fits 1994 1997 European Model Jaguar XJR 1012117191 LNA1800BA | eBay

Jaguar's heritage site says that the XJ6 has a different part number than the XJR but this listing claims that they are interchangeable...

I would take a chance on them being interchangeable, as the XJRs virtues didn't run to the electrical!!

I think that is a valid enough reason for me to give it a go

1996 JAGUAR XJR 4.0L L6 Supercharged Alternator / Generator | RockAuto

Interestingly, it's cheaper to buy a new alternator than a voltage regulator! Obviously it's a Chinese knock off.

Just so everyone knows, I got this email response from Jaguar via their heritage website:

"The alternators for XJ6 and XJR are different and are not interchangeable."

That's interesting. I still can't think of any electrical difference between the XJR and the XJ, but I am wondering whether the pulley alignment is different to accommodate the extra supercharger drive belt. I would still be tempted to take a punt on the refurbishment kit covering both, unless it is hideously expensive.

I can't either. They probably are electrically identical and likely different in their outer configurations.

I went through this even though the OP sounds like it is a bearing issue if it is locked up.

Mine was bad when I bought the car,bought a used one at the junk yard and still had the same problem.

Bought a brush and VR kit from Ebay $30.

The issue with both alternators was the diodes were fried,so I spent about a week trying to locate replacement diodes with no luck.

I ended up buying a rebuilt from eBay for $90 and when I received it the voltage regulator was a 3 wire plug in,does the XJR have a 2 wire or 3 wire plug?

I contacted the seller and they mailed me a replacement 2 wire plug,the down side is they had knurled the slip rings instead of replacing them so I will be lucky to get 6 month's out of the brushes.

Back to the diodes (rectifier),nobody but nobody lists them for the Jaguar,I called a supplier that has been in business of alternator and generator same family from the 1930s,they could also find no listing.

So anyways with car companies what they are I found it hard to believe that Denso built an alternator just for Jaguar special.

The X300 uses a 120 amp alternator Denso,1993 to 1997 dodge caravan uses the same 120 amp alternator in which the diodes are available.

I took the diode pack (rectifier) out of a used caravan and installed it into the Jag housing.

It does the same thing in converting the 12 volts into 120 amp with the voltage regulating against overcharging.

Why is it you can buy a rectifier for every car known to mankind unless it is for a X300 lol

So with
New slip rings,If needed
Bearings
Rectifier
Brush kit
Voltage regulator

$90 and you know what you have verses a rebuilt one that maybe just some parts were changed.

Denso rectifiers are easily repaired.

The rebuilder I like to use does not stock rectifiers.

They rebuilt a Denso for me a few years back.

Desoldered the diodes, installed uprated diodes
in a few minutes and charged a buck a diode.

Rebuilding the brush holder assembly was $5
for new brushes soldered into the existing
holder.

The reason that the interchange market lists
few parts for the Jaguar alternators is that the
original engineering drawings are proprietary
and marked that way by Denso.

Without the details in those drawings it is difficult
to say with certainty which parts are the correct
interchange.

Yup. The bearing is bad for sure.

The XJR has a 3 pin plug.

Thanks for sharing your experience and good luck with your alternator. I hope to have mine fixed as soon as I come across some free time...