Seized screws under roof flaps

After weeks of searching, I finally tracked down some Porsche roof bars for my 996. £240 for the bars and two Porsche cycle holders, so rather happy. Only problem is - when I came to fit the rack today, the small screws which are housed under the flaps on the roof wouldn't budge. My car is a 1998 and I doubt it has seen a roof rack before - so not really surprising that the screws have seized up. Has anyone else encountered this problem? My initial thoughts were to spray them with a bit of WD40 and leave overnight, then have another go. Although I read on a Pistonheads forum that once the screws seize, there's no option other than drilling them out (which will involve dropping the roof lining). Any ideas?

wd40 overnight can work wonders!then its down to you :grin: to tease the sods out.

I had the same problem and ended up having to replace the anchor plates in the roof. Apparently it is a common problem on early 996's, which used metal screws rather than the plastic screws found in later cars. I wrote up a post on the problem and solution on renntech, which you will fine here... www.renntech.org/forums/index.php/topic/16221-roof-rack-anchor-plates-part-number/ Greg

Thanks Greg. Have called around today (Porsche Apart, various breakers) and nobody has or can get hold of the replacement plates! My current plan is to drill out the screws and rethread with a 6mm tap (as per a Renntech post linked to your own posting).

before resorting to drilling out the screws, try a week of plusgas then get an impact driver with a very snug fitting bit. Then for the tricky bit, give it a bash with a club hammer. If it was me, i'd put some blankets over the roof just incase the driver slipped. There are three ways to undo seied screws. 1) Heat the surrounding area quickly so the metal expands. Not an option here 2) Impact driver & anti seize lube, lots of it 3) Get the drill out. Good luck

Well nothing would shift mine and the screw heads were pitifully weak. Drilling them out was no major issue though, just take your time.

Thanks both. The screws are now bathed in Plusgas, and I am then going to have a crack with an impact driver on Friday. However, as Magic Man points out, the screw heads are useless - even after using a snug-fitting bit and applying mild pressure to turn the screws manually with a standard screwdriver, the metal is starting to distort, meaning that the groove is starting to look a little worse for wear. I doubt that the Plusgas plus impact driver route will change that - if anything it will just completely destroy the screws, but am willing to give it a go anyway. Magic Man - drilling out the screws is my plan B. Once you had drilled out the screws, what is the next step? Did you re-tap the hole to match the screw for the roof rack bracket (I think it's a 6mm thread)? Or did you then pull out the roof anchor plate and insert new ones? I have managed to track some down from Porsch Apart (to be shipped in from Germany), but before ordering I want to see where I can get to just by drilling out the screws. Cheers

You might not need to re thread (tap) them, if you start off with a small dia drill bit and then move up through gradual sizes - the bolt will weaken as it's core is being drilled out and start to turn with the drill motion. My dad (back in the days of BA threads!) had a tapered, reverse threaded tool that would grip into drilled-bolts and extract them as it tightened up. Perhaps I'm being a bit optimistic but that's what I'd try first.

Did you manage to get the screws out OK or did you have to go down the bracket replacement route? I'm looking at what to do and am keen to see if anyone managed to get them out.

So was looking at mine as I have a set of roof bars to fit and found my bolts seized as well. I need to drill out but does anyone know how long the original bolts are?

My 996.2 doesnt have anything in threaded holes so presumably the nylon bolts were never fitted or its had a roof rack on at some point. Its difficult to measure but there seems to be about 12-14mm of thread in the captive nut. Using a calliper gauge the hole 22mm deep before it hits something inside the roof. Hope that helps. Ian

Perfect, so basically 14mm from top of where the thread sits then another 10mm until it hit something? That's good to hear that it doesn't bottom out.

Measurements were from bottom of channel rather than roofline. I'll try and do some accurate measurements later. Thinking a bit of wire with a 'L' bent at the end will locate the bottom of the threaded insert. Ian

I whipped mine out and drilled / tapped in a vice. Much less risky! Pretty easy to get them out. Replaced with a smear of silicone. You can buy new ones, they are listed by part number on rose passion so any OPC will get them.

I thought you had to drop headlining to get to them? Im fine with drilling insitu but if there not expensive and easyish to replace might just go that route.