Fuel filler cap - How to Change the Lock Barrel..

One problem with the F/TFs is that the fuel filler cap tends to fade and corrode over time. There are several options including painting them etc, but I just bought a good second hand one. The problem with this is that the replacement fuel cap will have the wrong key which means 2 keys on your key ring.  You can however swap your lock barrel onto the new fuel filler cap. If you remove the cap and look on the inside you will see a blue plastic shroud. 



You need to remove this as it holds the key barrel in place.  If you look at the end of the blue shroud you will see that there are 4 quadrants which clip under a raised section on the end of the lock barrel. 

 

You need to bend these quadrants back far enough that they release their hold on the barrel. 



And then pull the shroud away from the filler cap. 



You will then see a rubber o-ring which needs to be removed. 

 

Once the o-ring has been removed, hold the cap and push on the cream coloured part of the lock barrel so that you push the barrel through the cap and out towards the key end.  The o-ring is still in place in the picture but should be removed. 



 

And the barrel is removed. Now remove your barrel in the same way and push it back though the new filler cap. Don’t forget to fit the o-ring back onto the end of the barrel.



Reform the quadrants on the blue plastic shroud so that they are roughly the same shape and position before you levered them and then push the shroud onto the end of the barrel until it clicks into place.  You can only fit it on in one of 2 ways, make sure that you have it in the right position before pushing it home.  You can test this by turning the key and making sure it operates properly. 



You have now changed the lock and can fit the new filler cap to your car.  ​​​​​​​ 




 

Many thanks for this, just changed my barrel over into replacement cap following this. Quick reminder for all the novices, leave the key in when you remove the barrel or you will be chasing bits forever! I learnt the hard way!!!

Did this today when you pull the blue thing I couldn't do it due to my puny office / IT Geek hands so put a flat blade underneath and popped it off




Think I'll polish up the old one and see how it looks

Thanks for a great "how to", just swapped lock barrel to a new s/h one.

Made it so easy, with great pics.

Yep, another thanks from me.
Did this changeover this afternoon, 15 minutes well spent.

+1 well described procedure that is straightforward to follow and doesnt need the missing pictures.
The dismantling process is equally good for fixing a glitchy lock barrel where the key has started to get difficult to turn as most of the time it just needs a good clean

Notanumber wrote:

+1 well described procedure that is straightforward to follow and doesnt need the missing pictures.
The dismantling process is equally good for fixing a glitchy lock barrel where the key has started to get difficult to turn as most of the time it just needs a good clean

I saved pictures here if you need them:  https://www.mg-rover.org/threads/how-to-change-the-lock-barrel-on-your-fuel-filler-cap.370993/?post_id=3908259#post-3908259

I did it following the How to about one year ago. There were pictures then, I seem to remember.

Thanks so much, CJJ

Psymon has restored the photos!🫡