I still have OEM Lucas starters on both my XJ-Ss. The one on the '89 convertible is original, still works well. On the '79 coupe I rebuilt the starter when I also rebuilt a 2nd hand HE engine for it. Nothing really wrong with it, just needed cleaning up and the brushes were still good.
I never punish the starters, give them a 3 or 4 second burst when engine cold. Wait 5 seconds and another 3 or 4 seconds burst will usually fire up the engine. Stops the starter from overheating.
The Lucas starter is built like a battleship, no skimping on the design. Most likely fail is the solenoid main copper contact which just gets pitted. An easy fix.
Because it is direct drive it runs at lower RPM and draws more current than a geared starter and is electrically less efficient. The geared type runs at higher RPM and less current.
My preference is just to overhaul the Lucas starter, but if you do not want to spend 2 or 3 hours doing a thorough job buy a geared type.
I don’t believe Nippon Denso is part of Toyota, but they are the cream of the automotive electricals world, so used by all Japanese car manufacturers.
Gear reduction starters are pretty universal now as they draw less current for a given torque output at the bendix.
I don’t know if Jaguar has a rubber cap over the wire post…but when I had a motorcycle with a very exposed battery connection… I put one on that are used on riding lawnmowers… never had to worry about dropping something in there which would have been disastrous.
Yes 100% sure.
So i did have a rubber cap, but it was not a tight fit. I will try some other caps this time.
I would certainly trust ND products.
These replacement GR starters have been around for a long, long time. Not that I’ve researched it but I’m pretty sure that a lot of them were (and perhaps are still) “Brand-X” and not of the highest quality.
The two that I had…many years ago…came from one of the “usual Jaguar vendors” but carried no manufacturer identification. They probably were not the highest quality and that’s probably why my experience wasn’t all that great.
Parts quality has been a problem for a long time and is not getting better. And sometimes even the better vendors are selling not-so-good products…perhaps not knowingly in some cases.
When doing mods and upgrades we must take parts quality into consideration… along with all the other factors…when deciding if the juice will be worth the squeeze.
Cheers
DD
I think when I did my research way back when which I gleaned off a Land Rover forum they were starters made by Nippondenso starter and redone by Guftenson Machine.
They supply to a lot of vendors that we have used and British Starter offers the life time warranty.
I have no issues with mine touch wood, in fact I kind of like the quick over of the V-12 for starting.
I looked at my burned out starter, and except for a sticker on solenoid of rebuilder, i can’t find any markings of original manufacturer. I scraped away sticker, nothing underneath. Not sure what a genuine Denso starter is marked with. If it was just a sticker, that’s long gone. Or it could be a no name starter.
I will look at the replacement i just ordered when i get it next week. It was rebuilt in Germany, I’m guessing.
My burned out starter came from British Starters, who use Guftenson Machine in MA. They say they use genuine Denso starters.
Lifetime warranty, eh? Do you think I’ll be able to send mine back? Lol
AFAIK, Denso is not Nippon Denso though it appears they were owned by Toyota who still have a major shareholding, so…
Denso is partly the remnants of Lucas…
A national car parts supplier sold me a set of Denso glowplugs for one of my cars…which burned the relay unit to a crisp.
The retailer was good enough to provide four Beru plugs and cover the cost of a new Mercedes glow plug relay.
Looks like old habits die hard…
Denso was the new global name switch in 1996 for Nippondenso. So i use the names interchangeably. Denso remnants of Lucas? What!?
I am and will be quite happy with my rebuilt Denso, Nippondenso, or whatever you want to call it. Don’t care what happened with your plugs.
And my gawd, your contrarian and condescending posts are so annoying. Why?!
Nippon Denso became simply Denso 25-30 years ago. What changes accompanied the name change? I don’t know.
I’m not aware of any Lucas connection…but I’m not saying one doesn’t exist. Lucas sold its automotive division…and right to use the brand name “Lucas”… in 1996 or so. I think it has been resold a couple times since then.
Global manufacturing and distribution, combined with seemingly endless selling-off and splitting of brands, is one reason it’s difficult to know what you’re really buying. A lot of the brands I used to trust have lost a lot of their gloss in my experience.
“Label Engineering” has become the norm, it seems.
Cheers
DD
Ever heard of Lucas Epic diesel system, which is now Denso Epic.
Lucas diesel was absorbed into Denso.
Wow! You are so smart!!!
Oh please calm down, if you don’t like Mr. Dieselman I understand, and if you just ignore him he might one day buy an XJS to get your attention back. Or not. Or block him for a few months and you don’t have to see any of his posts, and peace is restored.
I have some knowledge and experience and just do a bit of research if I have queries. 
Nippon Denso was part of Toyota, but was sold off and the new company is Denso, which is made up of a number of acquisitions, such as Lucas, when they went bust.
Toyota have a 25% stake and less than 50% of Denso production is involved with Toyota.
Denso operate globally, but not in the aftermarket car parts business, mainly in automation and Hvac.
They have a parts picker for aftermarket, unfortunately, no starter motor for Jaguar Xjs.
About company | DENSO (denso-am.eu)
The good news is, it appears you only shorted out the solenoid and starter feed cable, not the armature, so repairs should be cheap.
To add, my glow plugs failure was the second set of Denso plugs the retailer had supplied, the first ones failing in short order but they would only replace with another set of Denso.
Two days later one plug went dead short and burned out the CAN controlled glow plug module.
Quite an expensive exercise for the retailer.