I bought my 74 TR6 seventeen years ago . It was sitting in the guys yard I bought it before I had my car stopped That’s a expensive story for another time . I got it home and the hose from the tappet cover was off . I plugged it back in and didn’t think about it Started it up and within a few minutes it started pushing oil out . Unplugged the hose after hours of search problem fixed . The hose to the Carbs and the missing canister was plugged . Fast forward to the other day , torqued the head and reset the valves . I rerouted the hoses from the carbs to Carbon canister from the tappet cover And started the motor. Shut it off and went in the house . As I was on a hot streak couple of days later i started it up to adjust the carbs ,no oil pressure That was because my oil was on the ground under the car When I rerouted the hoses I bent or crinkled one resulting in no vacuum .
With my car the motor needs to breath ,if not the pressure builds up and dumps it on the ground