My car has been stood for approximately 6 months because of front end collision damage. I repaired the engine bay and radiator. Checked the oil and levels full and still translucent (only 3000 miles since last service). While topping up the radiator I ran the car for approx 5 minutes for the thermostat to open. During this time extremely loud tappet noises were coming from the engine. I have removed the near side rocker cover and found very dry tappets also very very slight emulsification on the top of the cover. I cleaned the cover and refitted it. Struck up the engine again approx 2mins and then removed the cover to inspect it. The inlet tappets had a small film of oil the exhaust tappets were dry. The rocker cover was also clean with no oil except from a small amount from the cam chain. My questions I suppose are should more oil be present on the cover and how can I check the oil pressure without extremely expensive equipment.