Oil Pressure

[sonerainut]

Hello all!

The weather has improved and flying season has begun!

I have a general question regarding oil pressure. I'm in the green around 40 PSI (or just shy of that) at cruise, but when at idle it is really low. The oil pressure gauge I use is pretty coarse, but I guess it at idle the pressure is between 5 and 10 PSI. The temps are OK.

I noticed this on the last couple of flights without changing anything on the engine. I did replace the top mounted oil cooler with a larger remote cooler, but I don't recall the oil pressure being low at idle after the mod.

I plan on doing a calibration of the gauge before I do anything in case this is an instrumentation problem.

What is everyone else seeing? Should I be concerned - I know the pump is RPM dependent, so this might just be nature of the beast.

Has anyone had to "adjust" their oil pressure, if so what method did you use? Shims, adjustable valve, different springs?

I have a Great Plains 2180 with the as supplied standard oil pump and stock dual OPR setup.

Thanks everyone for the input.

If all goes well over the next couple of months, I plan on flying 35LR to OSH.

Lee

 

[splischke]

My oil pressure behaves exactly as you described -- 40 psi at cruise and <10 at idle.

-Scott

 

[eschrom]

In my driveway runups I've seen 60 psi while the tach was in the mid 2000's and about 30, give or take, in the 1000-1500 range. It may make a difference that my total engine time is still very low, measured in minutes, not hours.

I'll go out on a limb and postulate that these gages are not extremely accurate. One man's 20 may be another man's 30.

Ed
2LS with GP 2180

 

[Schmleff]

The rule of thumb is 10psi per 1000rpms. I see about the same thing you are describing.

 

[sonerainut]

All,

Cool! Dosent look like I have anything to worry about. I think I'll still calibrate the gauge/sender just so I know for sure.

This whole internet forum thing is great! I am only a few clicks away from a lot of good info and experience.

Lee

 

[phzabriskie]

Just curious what are you guys using as oil pressure senders? Westach has, 1)PRESSURE SENDERS/KV .5 TO 4.5 VOLT OUTPUT TRANSDUCER @ $219.80, and 2)PRESSURE SENDERS/240 OHM RESISTIVE SENDERS @ $57.90. Quite a difference in price!!
-Pete

 

[Schmleff]

I might be wrong here, but I have heard a number of times that electronic sensors tend to be inaccurate. I am using mechanical system.

 

[splischke]

Pete,

I have the Microflight Micro-1000 mechanical gauge. $37.95. Works great.

http://www.aircraftspruce.com/catalog/inpages/microflight1000.php

-Scott

 

[phzabriskie]

Great $190 dollars saved to put elsewhere. Jeurgen is online too and we're talking about panels. Jeff I would very greatfully take you up on your offer for your old panel. It looks like I may get to run this engine this summer.
-Pete