Oil Pressure does not go to 0

[Jeff_R]

The oil pressure on my Skyview reads 9 to 11 psi long after my engine (YIO-320 - started and run several times but not flown) has shut down -- even a week later it will read this amount of pressure. During taxing testing at around 1,600 RPM it peaks near 90 psi, which seems high, so I am thinking there might be a 10 psi offset in the reading. A separate Hobbs meter, connected in parallel with the oil pressure transducer, does not run after an engine shut down. Neither does the Skyview's hobb's is run, as I have run the Skyview for hours with the pressure showing 9 - 11 psi, but the total tach time is equal to the actual engine run time.

Any ideas?
Thanks,
Jeff

 

[dynonsupport]

The Hobbs needs 15psi to run, so that's not surprising. Which sensor are you using? The Kavlico, or the older style? If the older style, what's the resistance measure when power is off?

 

[Jeff_R]

Problem solved!

I measured the resistance from the terminal to the case (I have the older sender), and noted the Skyview indicated 12 psi. This was after the engine had not been run in 2 weeks. I then decided to remove the sender. Very little oil came out, but there was some. I cleaned it up and didn't notice any clogs, but when I remeasured the resistance, it was much lower. I reinstalled the sender and now the pressure indicats just 1 psi. The pressure seemed more reasonable when I then ran the engine, and after shutdown it quickly came back to 1 psi. I have no problem with a 1 psi error at the low end.

So, I guess there was some lind of clog or something in the sender that is now cleared, and it is working fine.

Strange, but glad it was something simple. (Yes, I recorded the resistances but forgot to bring them home. Rather irrelavant now! )

 

[acepilot59]

I have recently developed a similar problem, my indicated oil pressure is 13 psi 24 hours after the engine has been shut down. It has also started indicating about 6 psi higher at cruse with normal oil temperatures. (170 degeees F) I believe that I have the old style pressure transducer since it was installed in May of 2006. I also see a lot of fluctionation in my fuel pressure + or - 3 psi with no change in throttle. what are your thoughts about changeing out both transmitters for the new style. Are they more reliable and accurate?