Yup to remove them you need a special key - it's like an Allen key but 5-sided. If you don't have one then it could be tricky... if you're near York then you're welcome to borrow mine...
Shove it into the hole above 'Citroen'' and rotate anticlockwise... one side will probably be enough to release. The screw simply pulls the plastic end bits inward, which pulls hooks under the tabs on the roof.
Once you've got it off, you can replace the bolts with that weird 5-sided head for normal M6 Allen bolts - preferably stainless. Unfortunately if yours has been on a while it may well have corroded fairly solid... I broke one of the original bolts when trying to disassemble mine, which is how I know about replacing them!
Will shortly take delivery of some heavier duty AIKO bars as per this thread:
As the original Citroen ones aren't all that great IMO.
Thanks a lot! That's brilliant; just what I needed to know. I reckoned the hole above the Citroen mark was the key – but a no screwdriver I have worked. Now I know why!
Unfortunately, I'm in central Portugal, so York is a bit far off. And I've gotta get the bars off before taking a ferry in a week or two's time (otherwise I get into a different height band for pricing)! But I'll work it out. And the trick of replacing the screws is a good one. Very helpful!
Thanks again. Great forum for a new (secondhand!) Berlingo owner.
If all else fails just saw the bars in half :-)
Ha ha! I'll try a Citroen dealer first. If that's no good, I'll grind down a hex key to fit
So it turns out the bars were pretty rusty. Managed to get one of the bolts undone with a ground-down hex key; the others were totally seized up. But some wiggling around and wrenching at the bars loosened the clamps. So all is now good – except that the bars are essentially useless.
I sourced a new pair on E-bay for £90 + postage. Citroen originals. They come with the appropriate 5-face key for installation...
Thanks for the help – gave me the confidence to attack the problem head-on!