Hi,
I do know there a couple of threads about this subject. Nonetheless i think i could use some extra help.
I have a 2011 Lycoming factory rebuilt AEIO540-D. It has the "standard" Christen 801 for inverted oil system. I am currently using TOTAL aviation 15W50 (same as aeroshell 15w50).
Lately i have been experiencing a abnormal behaviour of the oil pressure when rolling inverted. During upright flight a get a steady 80 psi pressure. After i roll inverted the flicker of the oil pressure goes really low, down to 20 psi, and it take about 2-3 sec to recover to normal value 70 psi. After i do this a couple of times, the values get a bit better, but still below manual values and previous behaviour.
The manual states that the flicker can last about 1 sec or up to 5 sec if you have restrictor type fitting on oil pressure gauge. That seems to be the case of my gauge, so time lag is no problem here. The problem is that the manual also states that the pressure reduction should not be more than 30 psi, so 80 psi minus 30 psi, should be around 50psi. Before this later flights i was getting even better performance than the limits of the manual, but now, i am getting these low numbers. My maintenance company performed all the steps of the troubleshooting of the manual (nowadays the lycoming engine manual contains a section for the christen 801). Did not work, problem remains.
Any idea of problems not covered by the manual troubleshooting that could be leading to this? I have read about the O-ring in the plug behind the screen being worn out and about the hoses witdh (this last makes no sense because everything was ok a couple of flights ago).
Anyone with same situation?
Thank you a lot for your time and patiente.
(i have no maintenance experience, only flying and "reading" skills...)
I do know there a couple of threads about this subject. Nonetheless i think i could use some extra help.
I have a 2011 Lycoming factory rebuilt AEIO540-D. It has the "standard" Christen 801 for inverted oil system. I am currently using TOTAL aviation 15W50 (same as aeroshell 15w50).
Lately i have been experiencing a abnormal behaviour of the oil pressure when rolling inverted. During upright flight a get a steady 80 psi pressure. After i roll inverted the flicker of the oil pressure goes really low, down to 20 psi, and it take about 2-3 sec to recover to normal value 70 psi. After i do this a couple of times, the values get a bit better, but still below manual values and previous behaviour.
The manual states that the flicker can last about 1 sec or up to 5 sec if you have restrictor type fitting on oil pressure gauge. That seems to be the case of my gauge, so time lag is no problem here. The problem is that the manual also states that the pressure reduction should not be more than 30 psi, so 80 psi minus 30 psi, should be around 50psi. Before this later flights i was getting even better performance than the limits of the manual, but now, i am getting these low numbers. My maintenance company performed all the steps of the troubleshooting of the manual (nowadays the lycoming engine manual contains a section for the christen 801). Did not work, problem remains.
Any idea of problems not covered by the manual troubleshooting that could be leading to this? I have read about the O-ring in the plug behind the screen being worn out and about the hoses witdh (this last makes no sense because everything was ok a couple of flights ago).
Anyone with same situation?
Thank you a lot for your time and patiente.
(i have no maintenance experience, only flying and "reading" skills...)
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