Reseal roof rack hardware? (1 Viewer)

[jademica100]

I am replacing the hardware for attaching the roof bars to the body on my 100 series. What should I use to seal the threads? Silicone? Or should I use something that doesn't dry completely like permatex?

The bolts that I removed looked like they had regular silicone on the threads.

TIA

 

[kbfj621989]

I used this clear permatex when I reinstalled my roof rack. No leaks so far. Just squeeze some in each hole.

guide here: Remove or Install Your Factory Roof Rack - https://tlcfaq.com/main/2012/04/remove-or-install-your-factory-roof-rack/

 

[riffman12]

yep +1 to the clear RTV silicone. Used it on 3 rack installs and never had a leak.

 

[GerLC100]

I have added it to the top part of the thread (so the lower part can still properly work w/o a "lubricant" in the threads) and also added some between rail and bolt shortly before hitting the base.

 

[Super77]

Silicone RTV is not the right sealant for roof rack bolts. It can work, but butyl caulk and polyurethane sealant is what's commonly used at the factory. Silicone RTV is very thin and has little mechanical strength when squeezed into a film. Since the torque on the roof rack bolts is low (80 in/lb), you're relying somewhat on the sealant to keep the bolt from backing out. Polyurethanes like Sika makes are thicker and more 'rubbery' when cured than RTV.

You only need a little schmear on the upper half of the threads and where the thread meets the bolt's shoulder. Don't go overboard attempting so seal everything, you only need to prevent water ingress into the threaded M8 hole. The rest is essentially a controlled leak: if any water gets into the top of the roof rack mount, it needs to drip out and into the rain channel. The last thing you want is water pooling up in the mount's structure because you have sealed up any way for that water to escape. That will rust your hardware and create problems later.

Water always wins.

 

[Mike NXP]

This is the one and only product that you need . I spoke with 3M on the specific use case. The 4000 can seal underwater and also be removed in the future if needed. They have another version that will fully cure and wont be able to be removed again, but the 4000 is the better choice.. Going on 3+ years with mine and its still in prime condition and no leaks.. Super77 above is correct, silicone room temp vulcanizing is not the correct product. It can work but you want an adhesive sealant

Clean bolt, clean threads, use the proper sealant and you're good to go