Looking for advice please as to what I should use to seal the oil filter chamber cap/nut, or if sealant is needed at all. I’m in the process of changing the oil for the first time on my Rap and having removed the cap/nut it looks like some kind of sealant was used, presumably to stop it working loose or leaking. As usual, there are numerous sealants out there but possibly not all for this purpose. Many thanks.