Low oil pressure and temp.

[JimWoo50]

My 0-320 b3b with 92 hrs now usually has borderline low oil pressure at the very edge of the green arc while at cruise rpm. I am using XC 20-50 with a screen now but the pressure was low during break in with mineral oil also. The gauges are Vans and the pressure reading is taken from the accessory case. Before I had no more than 5 hrs I added 3 washers to the prv and pressure increased from 55 psi to 62 or so that I am seeing now. Sometimes the pressure maxes out at 70 at higher rpm.

My question is should I be concerned with this? I would make me feel better if my cruise o.p. was a little more toward the middle of the green arc. Especially as I would like to learn some light aerobatics and have read that higher o.p. is better for that. If indeed this low o.p. is something that should be remedied, could changing the prv spring to the 11713 white spring help? Or can I add more washers to the assembly; I thought I read somewhere that 3 was the maximum though but my friend at the airport with the same engine says I can add more.

Thanks in advance.

[Jesse]

Your title said low pressure and temp, but your post didn't talk about temp. Usually those two would go together to a certain extent. In any situations like this, I first like to establish that me sensor is reading correctly by testing with another sensor and instrument if possible. This will tell you if you do, indeed, have low pressure.

I usually see, if I remember correctly, 60's to 70's in flight. I don't like to see over 90 and 100 is redline. What is the range of your green arc?

As far as changing it, I'd call an engine shop for their recommendation, but I would verify that it is a problem before trying too hard to fix it. I know of cases where people couldn't get their rpm up high enough so they changed settings on the governor, only to realize that they weren't reading correctly and actually oversped the engine in trying to fix a problem that didnt exist. That is the beauty and the problem of digital gauges, IMHO.

[JimWoo50]

Will check the gauges Monday. Confident that they are accurate though. Low temps are probably caused by my installation of a oversize oil cooler thinking that I can always block it off. Not as serious to me than the low o.p.

[jim miller]

Originally Posted by JimWoo50

Will check the gauges Monday. Confident that they are accurate though. Low temps are probably caused by my installation of a oversize oil cooler thinking that I can always block it off. Not as serious to me than the low o.p.

Jim
I have had similar exp with oil pressure a little low on my 0235 C-1. I would of course check the gauge and if still low add more washers or change the spring. Do you have the short tower or long tower or the screw adjustable type of pressure valve? There are three or four different springs you can get
to use in the valve if washers alone don't fix. I think the max is three washers in the short tower and nine in the long (Double check this) I am not
even sure you can use any in the screw adjustable valve.