I always have a drop of oil on the head of oil sump bolt #2. I removed the bolt to inspect and could see the bearing cap side bolt (#18) through the hole. It's directly above the oil pan bolt and the thread goes all the way through to the side cap bolt. It looks like that the oil comes from the side bolt. I never removed that bolt. Its such a leak possible? Needs the side bolt thread to be sealed when installing (I couldn't find that requirement in the workshop manual)?

 

Hmmm, interesting. I always silicone the threads on all bolts, leak proof, rust proof, loosen proof.

 

I left the side bolt in place. Squeezed a bit of RTV into the hole at the top where it meets the side bolt, installed the sump bolt. Let's see what happens.