Cth6
Well Known Member
I wanted to solicit to see if anyone has crossed this bridge already with low oil pressure when temps are cooler.
O-320-E2C - Carbed / Mogas
Normal Oil Temps at cruise 170-180F
Normal Oil Pressure at cruise 70-80 PSI
Normal OAT above 80
P66 Victory 100, 31 Hours and 4 months since change. Good oil history.
340 SMOH
Burns 1QT per 10-12 Hrs
Tempest 48108 filter
This is my first year with this RV. The past two flights have been in colder weather (50-60 F). Yes Winter has made it to Florida.
With the oil cooler air shutter closed (no other changes to the RV), I can get the oil temps up to about 150-155F. EGT and CHTs are normal, maybe slightly lower.
The past two flights the oil pressure has built up to 60psi during run up and take off but then degrades to 45-50psi after 30 or 40 mins of flying at cruise. Pulling the power back to idle to land the oil pressure drops to 30-40 psi.
There are no leaks and oil burn has not changed.
I am used to oil pressure being high when the oil is colder. I am going to test the oil pressure with another gauge (I have the Vans OP sender) to rule out a bad sender. I am also going to check the vernatherm to see if it is stuck open/dirty. I can see the oil temp drop when I open the shutters so I know the cooler is passing oil even at 140F oil temp
If I don't see a change, my next step was to do an early oil change and cut the filter. I can reduce the airflow into the cowl, but I am not sure that will help.
Any thoughts on other areas to look at or test?
Thanks!
Chad
O-320-E2C - Carbed / Mogas
Normal Oil Temps at cruise 170-180F
Normal Oil Pressure at cruise 70-80 PSI
Normal OAT above 80
P66 Victory 100, 31 Hours and 4 months since change. Good oil history.
340 SMOH
Burns 1QT per 10-12 Hrs
Tempest 48108 filter
This is my first year with this RV. The past two flights have been in colder weather (50-60 F). Yes Winter has made it to Florida.
With the oil cooler air shutter closed (no other changes to the RV), I can get the oil temps up to about 150-155F. EGT and CHTs are normal, maybe slightly lower.
The past two flights the oil pressure has built up to 60psi during run up and take off but then degrades to 45-50psi after 30 or 40 mins of flying at cruise. Pulling the power back to idle to land the oil pressure drops to 30-40 psi.
There are no leaks and oil burn has not changed.
I am used to oil pressure being high when the oil is colder. I am going to test the oil pressure with another gauge (I have the Vans OP sender) to rule out a bad sender. I am also going to check the vernatherm to see if it is stuck open/dirty. I can see the oil temp drop when I open the shutters so I know the cooler is passing oil even at 140F oil temp
If I don't see a change, my next step was to do an early oil change and cut the filter. I can reduce the airflow into the cowl, but I am not sure that will help.
Any thoughts on other areas to look at or test?
Thanks!
Chad