Dec 2010/Jan 2011 Annual
Posted: Wed Dec 29, 2010 8:13 pm
I decided to annual my 7 a bit early to set up future winter annuals so I'm not down for an extended time in the summer...so, I put up a page on my website that will get updated each day (already has three entries) as I progress thru it...
http://www.chadandbrittne.com/December% ... annual.htm
The first thing I want to point out is something that matches exactly what Brian (Chesteen) ended up with after the first several hours...cracked baffling at the oil cooler. I noticed mine was cracked about a half inch after the 5 hour oil change, but between then and hour 25, it had progressed to about two inches. From 25-30, it ended up like this...
I'd say another hour or two, and the oil cooler would've been dangling off the back!
I should've fixed it at the 25 hour oil change, but for reasons I can't remember, I didn't.
The other big squawk (I have several small issues to address, but only two big ones), and it's not really even a squawk, technically...the compression on cylinder 3 was "only" 62/80. All the others were 72+. This raised my eyebrow, and even tho it is within Lycoming limits, I wanted to investigate further. After a day and a half looking at it with a borescope (every A&P in the shop had a look), we determined that it was not a burned valve, and that it was probably some carbon built up on the seat. That may still be the case, but we found the hydraulic lifter for the exhaust valve had some "gunk" in it that wasn't allowing the valve to seat fully. After that time consuming journey, we did a cold compression check, and it's up to 68 pounds, which should translate to somewhere back in the 70's when hot. The diagnosis is to fly it 5-10 hours, and check it again.
Just an fyi...if ya care to know what I'm doing instead of flying for a couple of weeks...
http://www.chadandbrittne.com/December% ... annual.htm
The first thing I want to point out is something that matches exactly what Brian (Chesteen) ended up with after the first several hours...cracked baffling at the oil cooler. I noticed mine was cracked about a half inch after the 5 hour oil change, but between then and hour 25, it had progressed to about two inches. From 25-30, it ended up like this...
I'd say another hour or two, and the oil cooler would've been dangling off the back!
I should've fixed it at the 25 hour oil change, but for reasons I can't remember, I didn't.The other big squawk (I have several small issues to address, but only two big ones), and it's not really even a squawk, technically...the compression on cylinder 3 was "only" 62/80. All the others were 72+. This raised my eyebrow, and even tho it is within Lycoming limits, I wanted to investigate further. After a day and a half looking at it with a borescope (every A&P in the shop had a look), we determined that it was not a burned valve, and that it was probably some carbon built up on the seat. That may still be the case, but we found the hydraulic lifter for the exhaust valve had some "gunk" in it that wasn't allowing the valve to seat fully. After that time consuming journey, we did a cold compression check, and it's up to 68 pounds, which should translate to somewhere back in the 70's when hot. The diagnosis is to fly it 5-10 hours, and check it again.
Just an fyi...if ya care to know what I'm doing instead of flying for a couple of weeks...
