Hi guys. Firstly I apologise if this is not kocher on here. I've got a bit of a yucky noise in my notch. I've done my best to capture it in a video. It sounds like a bit of a rattle, however the car seems to still have a lot of power it, on a hot day, using Nulon 15-30(?), or a hard run the oil light can come on the dash, I'm assuming I'm loosing oil pressure and it's possible related to this noise. I have not a lot of experience with this stuff and I was hoping someone knew what they were listening to and could tell me what it is that's causing this and if it's a fix at home job or something for a machine shop.

YouTube Video

Sounds like tappet noise to me. Check the tappet clearances and give it a good service.
We use Penrite HPR30 20W-60 oil in air cooled dubs. good stuff.