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So we (I) got the engine running and it looked like during the engine break in that the oil pressure was real good...40-50 PSI at high speed idle...

The engine has ran for about 1 cumulative hour with no strange noises and now however the oil pressure is more like 20 PSI at idle (according to the gauge) when the engine is either hot or cold. We are running straight 30 weight.

Naturally there can be something bad going on inside the engine to cause the low oil pressure...or there could be a spring issue inside the oil pump...or...an indicator problem.

I will go out tomorrow and install a mechanical oil pressure gauge however...to sleep better...is there something to look at in the oil pump and pressure relief spring? It looks like I can access the oil pump without major drama and it looks like there is a provision to access the spring and/or adjust the pressure?

Has anyone done this that can give any advice?

There is nothing wrong with the oil pressure in your car. However, a better oil for a new motor would be 10w-30. Even brand new (2015) engines have lower oil pressure at idle than on the road. Ford usually rigs the gauge to show a constant reading. As long as the motor has at least 10 psi per 1000 rpm it has sufficient lubrication.

The oil pressure relief valve is to set a maximum pressure but adjustment does not necessarily increase pressure under running conditions, much less hot idle conditions. Starting a cold engine and running it at faster than idle speeds will give you a maximum pressure situation and that's all the adjustment is intended for.

As Tim says, 20 psi at hot idle is quite adequate and not reason for concern.

Thank you.

I will start it this morning and record the oil pressure readings at low idle, fast idle, and higher RPM. Still messing around with the choke.