The importance of keeping current

Q: I have a Glasair with a Lycoming IO-360-B1E engine. After reading your article in the May 11 issue, I tried to get a copy of Lycoming’s SI1325A to see if I should change the timing from 25 to 20 degrees BTDC, but was not able to find that instruction. Can you help?

RON WALTERS, via email

A: Ron, I’m sorry if I caused some confusion in your mind and possibly others about the timing change on the Lycoming IO-360, so I hope I can clear things up here. The timing change was only for certain models of the IO-360 series engines and all of them were the 200-horsepower version, specifically the IO-360-A, C and D series excluding those utilizing the dual magneto, such as the IO-360-A1B6D model.

Your IO-360-B1E is a 180-horsepower version and is not included in the timing change covered in Lycoming Service Instruction 1325A. The proper timing for your specific engine is 25 degrees BTC. You can confirm this by checking your engine data plate or by referring to your Lycoming Operators Manual part number 60297-12.

As I’ve mentioned in the past, Lycoming has a publication for almost any technical question you may have but, as I understand, Lycoming does not provide its publications on the Internet except for the most recently released ones. Hopefully, this will change sometime in the near future, but until that change does come, I’d asked you to consider other sources for viewing the publications you may have an interest in.

Probably the easiest source would be from the facility that maintains your aircraft. As a licensed FAA Repair Station it should maintain current manufacturer publications and one of the things an FAA Principle Maintenance Inspector will look for when he visits a facility is the “approved data” used in the normal course of business. Also, any professional maintenance technician should have access to these publications, as well.

Another source that I always encouraged aircraft owners to consider is to subscribe to Lycoming Service Letters, Service Instructions, and Service Bulletins so that you’ll have easy access to them. You may subscribe to a complete set of these publications, including a one year subscription, for $210 at this time. Renewal for one year is now just $52.50. This is for domestic subscriptions only. Outside the US prices are slightly higher, but still one of the best investments anyone who owns an aircraft can make.

When you take a look at what you have invested in your aircraft, the cost of keeping current with any service information that may come from the manufacturer seems to be something to give serious consideration.

If you are interested in getting the publications, but feel the cost is a bit much, I recommend joining with two or three other owners of Lycoming-powered aircraft at your airport to reduce your overall cost. The costs will be spread out and everyone will benefit from the information. I’d suggest that someone in the group be designated as the librarian whose job it is to maintain the file by inserting any revisions are received. I think it’s important to note that all Lycoming publications are available directly from Lycoming by calling 570-327-7274.

I sure have gone around the barn on your question, Ron, but I hope it helps you and everyone who owns an aircraft to understand how important these manufacturers publications are. Having access to these is important and a valuable resource to support the investment in your aircraft.


Paul McBride, an expert on engines, retired after almost 40 years with Lycoming. Send your questions to:

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