Best oil for fordson super major

[huw717]

Hello There,
I have recently rebuilt a super major engine that was fitted in an old boat due to issues with coolant ending up in the sump due to corroded cylinder liners.
The engine now starts and runs beautifully and seems to have a lot more power than before. However i have noticed that when warm after a period of hard work , that the oil pressure on tickover falls to about 15 psi. I have had the crankshaft reground and fitted new shells etc, along with a new oil pump from agriline.
The oil in the engine at present is a fairly cheap and generic 20w50 product, after having run the engine for a couple of hours i would like to replace this with something of a better quality. I have seen various reccomendations on the site for a straight 30w mineral oil, and also for 20w30 multigrade. My knowledge of oil specifications is basic to say the least, can anybody offer any advice as to what oil I should look to buy?
Very best wishes
Huw

[Brian]

15 psi is not far out for a Super at tick over when hot.

I now use Morris 20/50W in all my tractors and am very happy with that.