I've had this plane for a couple years now and haven't really worried about it as it isn't out of limits and oil filter/analysis have all been normal but curious what is typical for an O-470? On start up and until its warmed up, my oil pressure is at the top of the gauge, not at red line but well above the green. By time I level off after climb out it is in the higher side of the green.Now that its colder out, obviously its running even closer to red line and its got me thinking about looking into it. I'm running Aeroshell 15W50 so switching to 80 would probably help with the cold but I'm curious what other people see in difference between start up and hot pressure? This is all on the stock Cessna gauge so Ill get a test gauge on order to verify actual pressure. Manual doesn't show any washers with the pressure relief spring but guess I better pull the plug and make sure someone hasn't thrown some in there. Thanks

I have a "K" that is basically the same. When I overhauled it back in 1995, I took a pump with integral oil filter off a U that the State police ran on a 182 and put it on without touching the pump. It ran about 75% into the green where I liked it. I had a shop in Omaha overhaul the engine again and whatever they did, it runs right at the top of the green. On first takeoff it gets into the yellow a ways but still below the red. I have a copper tube tapped into the oil galley between number 2 and 4 cylinders going to the gauge.

I’ve run two versions of 470s, both did exactly as OP described. If it was above, say 50 degrees out I wouldn’t notice anything, but as it got colder, it was typical to see high oil pressure on startup, running well above the green for first 10 minutes of flight or so, then settling down to the middle of the green. Never really worried about it. Maybe I should have?

The O-470L on my 182 runs the same way with 1400 SMOH and no issues. The R985 on my Ag Cat goes to 95-100 psi on almost every takeoff all through the summer, 900 SMOH and it’s running strong.

My O-470R produces the same indications, running the same oil as the OP.

I recently switched to an EI digital oil pressure gauge, and my startup pressure is typically a few psi in to the yellow arc and stays there until some point during climbout/cruise.

Always just figured that oil pressure on the slightly high side is better than the alternative.

The good news is that the oil pressure hits the green immediately after startup, so startup wear is minimized in theory.

My o-300D does this. Oil pressure is right at 45psi until it warms up. In the winter time I use an oil pan heater to get the oil warmed up before I start. Once the oil temp goes above 150, everything is back under 40psi like it should be.

Living in Alaska, and not having an oil cooler on my small engine, I block off the vent to the pan as soon as the weather drops into the 30's.

I always figured it meant my bottom end was good.

schu

That is what I was hoping to hear, thanks guys! I didn't worry about it for almost two years but recently did an IPC with an 8000 hour CFI and seemed to think it was pretty odd so got my wondering.