Good morning,
I was a member of the forum before the major format change years ago known as Brockster. I was unable to transfer to new format at the time because I no longer had access to email associated with VAF to get new password. I just recently reregistered as Brocker.
I noticed doing my borescope inspection recently that #4 cylinder has developed some small dark marks near the top of the cylinder at roughly 45, 135 and 225 degrees when looking at the cylinder from the side and top of valve cover being zero degrees. All other cylinders are fine. The O-320-E2G 150 hp engine has 275 hours, uses no oil, and runs fine. Oil screen and oil filter media show no findings this time and when previously checked. I use two SDS CPI -1 electronic ignitions and Phillips X/C and AvBlend. This cylinder has a compression of 78. All four cylinders are the same being Lycoming 05K21237-A cylinders that were overhauled by ECi in 2006. They don’t fall under ECi AD because they are not ECi cylinders. Cylinder has CermNil coating. See attached serviceable tag. I estimate the individual dark spots to be 3/16-1/4”. Disregard the brownish color as it is caused by light reflecting and not corrosion. Used a VA-400 borescope. Oil pressure, CHT and EGT all normal. CHT 340 and EGT 1400. I have EI UBG-16 engine monitor and after downloading is a good average. Has anyone seen anything similar. Currently just keeping a close watch on it and flying it. I provided pictures of valves as an FYI.
Thank you,
Paul Dannebrock
N884RV RV-9A
I was a member of the forum before the major format change years ago known as Brockster. I was unable to transfer to new format at the time because I no longer had access to email associated with VAF to get new password. I just recently reregistered as Brocker.
I noticed doing my borescope inspection recently that #4 cylinder has developed some small dark marks near the top of the cylinder at roughly 45, 135 and 225 degrees when looking at the cylinder from the side and top of valve cover being zero degrees. All other cylinders are fine. The O-320-E2G 150 hp engine has 275 hours, uses no oil, and runs fine. Oil screen and oil filter media show no findings this time and when previously checked. I use two SDS CPI -1 electronic ignitions and Phillips X/C and AvBlend. This cylinder has a compression of 78. All four cylinders are the same being Lycoming 05K21237-A cylinders that were overhauled by ECi in 2006. They don’t fall under ECi AD because they are not ECi cylinders. Cylinder has CermNil coating. See attached serviceable tag. I estimate the individual dark spots to be 3/16-1/4”. Disregard the brownish color as it is caused by light reflecting and not corrosion. Used a VA-400 borescope. Oil pressure, CHT and EGT all normal. CHT 340 and EGT 1400. I have EI UBG-16 engine monitor and after downloading is a good average. Has anyone seen anything similar. Currently just keeping a close watch on it and flying it. I provided pictures of valves as an FYI.
Thank you,
Paul Dannebrock
N884RV RV-9A
