Q: I am about to change my Alfa Romeo boxer engine to a Lycoming O-360A1F1 on my experimental Glastar aircraft. I read your answer recently to a question if LASAR is really useful (Will my engine benefit from new technology? Jan. 12 issue). Its actual price is $2,500. Do you think that it is really […]
Ask Paul: Why do my serial numbers differ?
A: I have a narrow deck configuration in my 1964 PA 30-270. The first entry in the aircraft logbook, made on Jan. 3, 1964, shows radio installation and LE serial #S or L 606-55 and the RE L 640-55. However the engine log books show LE L 938-55 and RE L 909-55 and the first […]
Ask Paul: The seal of approval
Q: We’re building an RV-6A using an O-360 narrow deck engine. There are six studs that hold this engine together. The center studs are wider at the base than the outer four studs. The case has an indentation where the seals fit. All six are counterbored. The size of the center studs at the base […]
Ask Paul: Use it or lose it
Q: I am considering buying a plane with a Lycoming 540 factory rebuilt engine. TSOH is 50 hours. The problem is the engine was installed five years ago with a new turbo and the owner has not flown it much since, although it has flown a few hours recently. There is a lot of chatter […]
Ask Paul: More on hot engine starts
Q: I’d like to offer my response to a hot engine start (What is the procedure for a hot engine start?). If I know I’m going to have a quick turnaround after engine shutdown, this is what I do: I throttle up to about 1,500 rpm, then I turn the fuel selector to off. By […]
Ask Paul: Why are Piper and Cessna mag checks different?
Q: During a checkout in a Piper Cherokee, (I had only Cessna experience), I asked the CFI why Piper has me check the mags at 2,000 rpm and Cessna at 1,700 rpm on what is, essentially, the same engine? My opinion is that it is not a deal breaker to not have exactly the rpm […]
Will my engine benefit from new technology?
Q: The O233 LSA engine uses the new E-mag electronic ignition that they say advances the timing to 38° BTDC, much like other systems. Does this much spark advance also have Lycoming’s blessing for the O320 and O360? I realize that the spark advance is rpm and manifold pressure controlled. LYLE FORSGREN, via e-mail A: […]
What is the procedure for a hot engine start?
Q: I have a Grumman Yankee Model AA-1 with a Lycoming O-235L 108-hp engine. What is the procedure for a “hot engine” start? When I shut down the engine, I run it lean at 1,800 rpm for about 10 seconds before I pull the mixture. Then, when the engine is cold, it starts right away. […]
Ask Paul: Narrow deck cylinders, the Twin Comanche and a Lycoming milestone
Geez, it’s really beginning to look like I’m losing it when it comes to misstating things in my columns. The most recent concerned the “Wide Deck” vs “Narrow Deck” cylinder column in my last column. I thought I’d explained the difference between the two and used an example of the Piper Twin Comanche PA-30 as […]

