IO 320 fuel pressure

[kentb]

Last night I finally got a chance to fly after a month tending to other things.
Plane start fine and all was well at the run-up, but as I taxied to take off the EFIS squawked High Oil Pressure. It was at 40 lbs. Usually it runs around 23-26 lbs.

I turned on and off the electric pump and that made no difference. I ran the engine up to 2500 rpm for a minute (it helps with fowled plugs). The pressure came down to about 32 lbs (in the yellow). I ran it up again for another minute and the results was 29 lbs.

I proceeded on my flight watching the fuel pressure. After take off the pressure dropped to 27 lbs.

My questions are:

1. What happened to cause this.
2. What should my pressure setting for normal operation be on an IO-320?
(what to set as the lower and upper limits on the yellow and red zones).

Kent

[Dan B]

On my IO-320 (a factory engine), my engine data log shows the fuel pressure remains between 25 and 28 psi at all RPM. Mostly it remains between 26 and 27 psi.

My Lycoming Operators Manual (IO-320-D Series) says "Inlet to fuel injector", Maximum 45psi/ Minimum 12psi