XJ12 locked fuel caps

I have a 1974 XJ12. my keys were recently stolen, so I need to rekey the entire car, minus the ignition. my fuel filler caps are currently locked. is there a way to open the lids to remove the screws?

A locksmith can probably “pick them”…

Or brute force. Drill the tumblers…

Replace. with good used or NOS stock.

If in USA, David Boger at everydayxj.


Obviously you need to change the locks, David - for security reasons…

But to do so you really need the ‘original’ keys; take the glove compartment lid to a locksmith - to make a copy from that lock.

But honestly; why didn’t you make spare keys - losing keys, one way or another, is not uncommon…

xj6 85 Sov Europe (UK/NZ)

Shit happens. I would get someone to pick them and then change the lid. Maybe you can drift the hinge of the flap out instead and get them open that way? I’ll look at it tomorrow- New locks with keys can be found, or just never lock them again.

On the rear of the fuel cap (opposite side of the key) you will see a little peg, where the cap rotates to open. Hammer it out and you will be able to release it.

excellent. I’ll try that. thanx

There are companies out there that can cut a new key from an existing lock.
But beware!
Jaguar supplied two sets of three keys with an XJ:

  • Master key that unlocks everything, including the ignition
  • Valet key that unlocks only the ignition
  • duplicate key that unlocks everything except the ignition

The best way to go when you want to keep using the original locks, is to dismantle the ignition lock and have a key cut from that one.
The door locks and the glovebox lock can be adjusted to a new key, so the safe way to go would be buying an new original ingnition lock with the keyset and have the other locks modified to the new keys.

Beware: the peg only comes out to one side. Examine closely which…

I looked at it briefly and unless I missed something I think the flap comes off when said hinge / roll pin is out.

I haven’t looked at it yet, but from my research, I find that the '74 models have the fuel caps flush with the body, so not sure if I’ll be able to access the pins if they’re recessed. I’ll be looking at it tomorrow.

Negative, Patrick; the ‘owners’ key unlocks everything except the ignition - which has a separate key with an entirely different blank. The ‘valet’ operates all locks - except the glove compartment and boot…

And as an aside; central locking locks the boot, but does not unlock it. With lost keys; do not use the central locking…:slight_smile:

xj6 85 Sov Europe (UK/NZ)

Frank you’re right, I stand corrected.
I saw a quick fix for the boot lock somewhere a long time ago.
With this fix, central locking would lock and unlock the boot.
Anyone here know of this trick?

so, I removed the pin, still not able to remove the lid. I did some more research, looked at some pictures. I believe that the locking finger is preventing me from removing the lid. I’m looking at my last option, before I’m forced to drop the fuel tanks, is to attempt to reach up and remove the retainer clip at the bottom of the tumbler assembly. if I can do that, I can remove the assembly, turn the locking finger, then I’ll be able to open the lid. hopefully I won’t lose any parts in the process.

You can drift out the pin but you know that now. Have I been stupid? Or maybe my lock is different, anyways, have someone pick the locks then. You can buy decent fuel flaps or parts if you need to replace them so all is not lost if something gives.

I’ve ordered a new (used) set of complete units with keys. I’m still going to try to remove the old tumblers, more for the challenge than anything else. once I receive my replacement sets, then yes, I won’t feel bad if I destroy the old ones…

1 Like

I do love a good challenge. I’m learning my Jag the hard way, in certain areas, but I always look at options…I’ve always found that there’s more than one way to do things or get things done.

1 Like

David Jauch, what year is your car? if yours is newer than mine, chances are your caps sit higher than mine. my car is a '74, so mine are recessed into the body (flush with the body), so I can’t move the lids forward once I remove the pin. plus, from the research I’ve done, the locking finger, in the locked position, is preventing me from lifting the cap off, hence my last option. as much as I hate destroying perfectly good parts, my thought is: if I can remove the old tumblers without destroying them, I can have them keyed and sell them on ebay to retrieve some of my cost of the new/used keyed set I’ve ordered, plus save another soul that may be looking for them. I’m sure someone else will need them.

no such luck Aristides. the locking finger below the barrel the tumblers sit in, prevents me from lifting the cap off. I’m looking at the option of reaching up underneath and removing the clip holding the tumblers in place. I can then remove the tumblers, then I should be able to open the lid after turning the locking finger to open the cap.

The raised caps came with the unleaded requirement, they somehow couldn’t fit the new filler neck (narrower and what else?) so they raised it. European XJ6 didn’t have them so I have the flush ones on both. But I think I got something terribly wrong and will look again tomorrow. Removing the clip isn’t such a bad idea either… you will get there one way or another.

Maybe even you can pick the locks with some cheap equipment. Beats removing the tank or destroying the cap or lock! I think the lock isn’t the hardest to pick but I only ever picked one such lock and it was more luck than talent. Not impossible.

Honestly, David B; you need one barrel, the glove compartment one, to copy keys that will operate all locks - including the filler lids. Rendering the ordered set superfluous - which you can then sell back on the ebuy. And save yourself a lot of bother…:slight_smile:

Admittedly a security risk with stolen keys, but still. But you can at least then unlock the filler lids (with no problem) - which is likely required for changing their barrels…

xj6 85 Sov Europe (UK/NZ)

1 Like