Would be nice to get your thoughts as I got contradicting information from different parties…
I am talking about the Lycoming SB 388 C means the “wobble test” for the exhaust valve guides and stems. Engine is an O 320 E3D with 160 hp upgrade by RAM STC which had been overhauled in 2009. At that time new “Hi-Chrome” exhaust valve guides and valves had been installed which led to the increased 1000 h inspection interval recommendation by Lycoming. I am not experiencing any kind of so called “morning sickness” so far, engine is running fine. BTW: No Engine Monitor available on board currently.
My question is now: Is this really necessary and providing reliable results? I am afraid that (assuming the possible risks for this inspection conducted by an inexperienced or unmotivated mechanic) that it will do more harm than good, and I would maybe face a mechanical failure afterwards. Occurring 6-8 hour (that’s what they told me) labor costs at the shop are another issue to mention.
Could a 100 h borescope inspection do not even the same or better in evaluating the condition of the exhaust valves? As far as I can remember Mike Bush has been in favor of this approach, but I could be wrong.
I am talking about the Lycoming SB 388 C means the “wobble test” for the exhaust valve guides and stems. Engine is an O 320 E3D with 160 hp upgrade by RAM STC which had been overhauled in 2009. At that time new “Hi-Chrome” exhaust valve guides and valves had been installed which led to the increased 1000 h inspection interval recommendation by Lycoming. I am not experiencing any kind of so called “morning sickness” so far, engine is running fine. BTW: No Engine Monitor available on board currently.
My question is now: Is this really necessary and providing reliable results? I am afraid that (assuming the possible risks for this inspection conducted by an inexperienced or unmotivated mechanic) that it will do more harm than good, and I would maybe face a mechanical failure afterwards. Occurring 6-8 hour (that’s what they told me) labor costs at the shop are another issue to mention.
Could a 100 h borescope inspection do not even the same or better in evaluating the condition of the exhaust valves? As far as I can remember Mike Bush has been in favor of this approach, but I could be wrong.
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