If you own a Lycoming Engine, you probably think of it as a piece of tried and true technology that has been around for so long there is not much anyone can discover that is new. And... you'd be wrong!
Since I attended the factory service school last winter, I have been subscribed to their update service for Service Bulletins, Letters, and Notes – and I have been amazed at the volume of material I receive on a monthly basis. For those who think that Lycoming is just producing the same old engines and parts over and over, with little going on in the realm of engineering, the surprise is that they are spending a lot of time on upgrades and customer support.
Of course, in the Experimental world, complying with Service Bulletins (even those labeled Mandatory) is voluntary... although may will argue about the validity of insurance claims and the potential liability of ignoring them. It should also be remembered that Lycoming produces a huge variety of specific models of engines – even though they have only a few basic product lines, the variations are endless. Many Bulletins and Notes apply to very specific engine configurations or very small serial number ranges, so its not like we all need to be opening up our cowlings every time an envelope arrives from Pennsylvania.
It is worth it, however, to pay attention to web forums and sites for your aircraft and engine to catch news of bulletins that might apply. Many are changes to techniques used when overhauling or working on these power plants, so they only apply when maintenance is being done. Occasionally news will come out that mandates an inspection or preventive action – and those generally get wide distribution. And if an AD is issued by the FAA that mandates implementation of a factory Bulletin, it's worth paying attention to – if only so that you can make an informed decision on whether or not to implement it on your experimental motor.
The interesting news I received in the last couple of envelopes is that Lycoming is planning to go paperless – that all of this information is going to be online, and that they will stop shipping paper. I don’t know if that means that it will al be freely available, or if a subscription will still be required – but saving trees and making information available electronically is usually a plus.