Oil Change Question 1982 300D

[jfikentscher]

What's with the hose (coolant?) behind the oil filter casing? Putting the cap back on was a bear. Really had to press on that hose to replace the cap. Should I have loosened the radiator cap to let off some pressure? Do you remove this hose prior to the oil change?

How about the O ring. Do you use some sealant on it to help it stay in place while replacing the cap?

This is our first DIY oil change on the '82. I have mine done at a local shop, but my son wanted to save a couple of bucks. He used Rotella and a new filter.

Any info appreciated.

Regards,

Joe