John,I presume we are talking about an M Type?Oil pressure is very average, and nothing to do with your problem.The first thing you must address is the temperature gauge if you are running at 150C.That is 1 1/2 times boiling point!Assuming the gauge is disfunctional, and that you are not continuously boiling the coolant, it would be quite normal for a radiator, having been filled to the brim, to displace 1.5L water through the overflow system as the water warms up and expands.Try not to top up the radiator before doing quite a few more miles and determine if the 1.5L is a fairly constant refill volume.If it is, then you don't need to investigate further (or top up), apart from the gauge of course! Roger  
8 January 2021 at 7:45 PM #5702
Ben Stevens
Keymaster

John,I presume we are talking about an M Type?Oil pressure is very average, and nothing to do with your problem.The first thing you must address is the temperature gauge if you are running at 150C.That is 1 1/2 times boiling point!Assuming the gauge is disfunctional, and that you are not continuously boiling the coolant, it would be quite normal for a radiator, having been filled to the brim, to displace 1.5L water through the overflow system as the water warms up and expands.Try not to top up the radiator before doing quite a few more miles and determine if the 1.5L is a fairly constant refill volume.If it is, then you don’t need to investigate further (or top up), apart from the gauge of course!

Roger