I recently bought a 1986 R65 BMW. When I went to adjust the valves I noticed that the previous owner had done a fix to his right cylinder head nut channel so that I assume oil would not leak out of it. It was basically a high heat type of gummy substance that would not detoriate and allow oil to pass through the channel. I wanted to replace the gaskets on the cylinder head and this gummy stuff had to come off. The question I have is what type of gummy stuff do you think was used to create the seal. Or what should I use to create another temporary seal. Or are there other solutions out there I could try without buying a whole new cylinder body? Thanks in advance for any help. Attached is a pic of what I have to work with.