Jeff R

Well Known Member
I am getting close to my first engine start and have started to check the oil and fuel lines for pressure readings. I had a buddy spin the prop by hand, with the top plugs out, and the Dynon Skyview indicated around 40 psi of pressure after few rotations. Great! I have oil pressure!

Well, he stopped spinning and I waited for the pressure to go back down. It didn't. For a good minute it fluctuated between 35 to 45 psi. It started trending down, but after several minutes was still around 25 psi, fluctuating a bit. I checked an hour or two later and it was 13 psi. Prior to the test it had read 0.

All I can think of is that the restrictor fitting to the oil pressure transducer might be clogged such that it cannot relieve the pressure. I didn't try to disconnect the fitting as it still showed pressure, but wonder if anyone else can come up with another reason or how I best go about solving it.

It would not be good to have a oil pressure guage that indicated all was well when your actual pressure was heading south.
 
http://www.vansairforce.com/community/showthread.php?t=83141

this is a similar thread. i suggested a non electric oil pres gauge as a rock solid backup. i am glad i have both. my electric has given me glitches over the years. it is a required instrument to be 'legal'. :)

Do you have any pix or part number as where it gets plugged in and how it works. I thought there was only one location (IO-360) at least for the oil pressure sensor.

Thanks
 
I called up Van's and stumped the guy who answered, but he asked the old timers and they said that it was probably due to my having a new engine in which the preservation grease was cold and was blocking things, thus causing the pressure to stay high. They think that when I run the engine the grease will warm up and soften, then flow out, clearing the passages.

Seems reasonable, and the engine has been sitting for several years (bought new from Lycoming) so maybe the original preservation fluid has hardened up a bit inside. I still think I will remove the oil pressure hose and blow it clean, and check the sender for signs of contamination. It is possible stuff was pushed up inside and is blocking things.

I won't be able to check this out, probably, for 2 weeks. I will report back if I find anything interesting.

The sender was supplied by Van's as part of the firewall forward package, if my memory serves me correctly.