Ask Paul

QUESTION: I have had instructors insist that I lean the engine while taxiing my O-320 Lycoming. My current Citabria has a JPI 700 engine analyzer with fuel flow. In the testing that I have done, the EGT will change less than 20° and fuel flow less than 0.1 gallon when adjusting mixture at less than […]

QUESTION: A friend has an O-320 in his hangar. I have only the following data, and am wondering how or where I can use these data to determine exactly which engine this is. Data plate says: O-320, eng #2689-27. The case is cast with the number L-17001-27A. I tried using the Lycoming website, hoping for […]

I have a Lycoming O-320-D2A that will be going into a Wittman Tailwind. The crankcase and crankshaft are yellow tagged. The camshaft is really pitted and will need to be replaced. I imagine the followers will need replacing also unless refurbishing them isn’t a big deal. My question is this: There’s a possibility that I […]

I have a high-wing homebuilt aircraft into which I have installed an IO-360-A1B 200-hp Lycoming salvaged from a Lake Amphiban, with 660 TT. My problem is that it makes loud popping noises at low RPM, such as when landing or taxiing. I have a cross-over type exhaust, and have had a mechanic check both the […]

I own a 1962 Piper Colt with a O-235-C1B engine. My operator manual says that I should have 115 hp at 2800 RPM. At what point would I achieve highest RPM? On takeoff? Level flight at full throttle? I never see that high of RPM even in level flight at full throttle. On takeoff, I […]

Cessna 182s have been burdened by a 1,500 hour TBO for many years. However, the O-470-U engine is now available with a 2,000 hour TBO. What possibly could they have done to the engine to extend the TBO by 33%? MARC COAN Taos, N.M.   While my background is primarily in Lycoming engines, I think […]

I have a Lycoming AEIO-360 in my Pitts S1S. I have been running AeroShell 100W Plus for years. Some buddies I fly with have been using an Amsoil oil (I’m not sure the number). What is the best oil and weight to run in this engine? Thanks. CHUCK ROBERTS via email Chuck, yours is one […]

How about a discussion of the scalloped wheel on the injector pump for an IO540-C4B5 engine? My engine will “”load up”” at idle and I have to run the rpm up to about 1,200 quite often during taxi. Also the engine will “”talk to you”” on final with the throttle closed. I have tried the […]

I have a 2005 Robinson R-44 Clipper II that I purchased new. The engine is a 540 injected Lycoming. I broke the engine in on mineral oil as suggested and changed to ashless oil after the initial 50 hours of break in. The ship has used about 1 quart of oil per every four hours […]