This is a preventative measure. As the engine warms up. I fitted a rebuilt temperature/oil gauge to a midget and had trouble convincing the owner that the pressure was in fact the same as before but her previous gauge had been wrong! (i had checked the new gauge before fining. You mention that you have to put the oil pressure line into a can or so. Since the spring is the easiest. Should keep it as an exhibit. Down to about 10-15 at warm idle.
Mg midget loses oil pressure. Net is published in the uk. Use a #10 spring lockwasher, twisted flat, to act as a shim between the valve and spring, to boost the oil pressure. (or maybe your idle speed is. This thread is from the archive. Welcome to our resource for mg car information. I would not be unduely. Told me that i need a new engine now and its dangerous to drive it.
Or, you may elect to do the whole job at once. Spring corrected the problem.