Sudden raise in oil PSI?

[RudiGreyling]

Hi RVators,

I am new to lyco's so I'll ask here for some unbiased opinions.

Coming back from a 3H40 long X-country flight last week my oil pressure jumped from the usual 80PSI in the fast cruise to 90PSI which I understand is the bottom of the yellow arc. (red is 100PSI?). It happened during the descent during the last 30 minutes of the flight and remained there 89 to 91 PSI for 30 minutes.

It has never before reached that high...Cause for concern? Where to start looking.

Some other info: Engine XP-IO-360, 200 HOURS since new, oil consumption +/- 1 quart every 4 hours, 3 month old blow by's 77,78,76,78. Fixed Pitch prop, cruises at 2600 RPM LOP at altitudes ussualy 7,500 to 11,500 ft (our airfield is at 5,500 ft). It is time for a 25 hour engine oil change in 40 minutes time, so the oil is close to being replaced...

Thanks in advance,
Rudi

[mahlon_r]

If the oil cooled off considerably, the pressure will naturally go up a bit. If it was cold out and the oil wasn't at normal temp, higher pressure then normal, would be natural.
Good luck and Happy New Year,
Mahlon
?The opinions and information provided in this and all of my posts are hopefully helpful to you. Please use the information provided responsibly and at your own risk."

[WilburD2]

Rudi: Take a look at the engine manuals. If your lube pump on the engine has a pressure regulator, It might be something as simple is a hunk of leftover metal shaving or something from manufacturing got stuck in the regulator piston and jammed it open a little further than factory specs. The manuals will walk you thru pulling the piston and cleaning it and readjusting to specs. Good hunting!

[vic syracuse]

I wouldn't get carried away doing anything yet. Mahlon is right---you can almost track oil pressure with temps when using single weight oil this time of year. Pressure will go up in a descent in the cold weather as the oil temps in our RV's usually drop quite fast when the power is reduced.

Vic