Ask Paul: Tips to getting Dad’s Pacer flying again

Q: I was reading your explanation on the difference between narrow deck and wide deck Lycomings — what an excellent piece of writing. My interest is that my brother Lee and I have my Dad’s PA-20 and, while stored indoors, it hasn’t flown since 1964 or so, but I’m thinking (perhaps foolishly) about putting it back together. I’m thinking the old O-290-D-2 (while in excellent shape and only 200 TT, but 7/16ths valves) will have to go. An O-320 is approved in the Wag Aero and Copper River STCs for the PA-20 (so is a 160 by another company). I don’t know why the O-320 works out so well in the Pacers, it’s only another 15 hp.

The big question is that I have found several narrow deck O-320s for sale and wondered if that engine is any more or less worthwhile than the wide deck version. [Read more…]

Troubleshooting a rough-running engine

Q: My Lycoming TIO-540 engine on my Cessna T206H is running very rough at max power setting. I recently replaced one dud cylinder due to very low compression. The ring gaps were wide and exhaust valve guide and seat were bad. Presently all compressions are good, ignition timing is good, and turbo giving boost. The prop looks OK. The engine has TT of 375 hours. The plane is AOG in a remote location. Any ideas?

COLIN WARD, via email

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Buyer beware

Please help me! Some of you who know me are probably saying I’ve needed help for years, but this is something even more serious than helping some old guy who’s been in this industry for a long time. I’m asking all of you to do your small part in getting the word out about the importance of getting a good pre-purchase inspection before buying an airplane.

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Ask Paul: What is proper timing for my engine?

Q: I am an Italian homebuilder of a Van’s RV-3. I read on the Internet that you are an expert of Lycoming and I want to impose on your kindness. I am ready to make the timing on my Lycoming O-290 D2 but there is a little doubt about the timing degrees because the O-290 is not a common engine in Italy, as it was used only by the Italian Army in a PA18. An AD issued in 1954 changed the timing at 18° (label on engine) to prevent detonation, probably with 80/87 fuel. If I use 100LL, will I have to change the timing? Many thanks in advance and sorry for my bad English.


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Ask Paul: Should I worry about my #2 cylinder?


Q: I had my Lycoming 0-360-A1A rebuilt at Victor Aviation in 2001 — new crank, new cam, new pistons with new Millennium cylinders. The engine, which now has about 400 hours on it, has digital cylinder head gauge probes in each cylinder. My question: On a warm summer day in Alaska (75°F), with a load in the plane on floats, during climb out, the #2 cylinder head temperature hits 400°F. [Read more…]

Ask Paul: Solving a mystery

Paul McBride, an expert on engines, retired after almost 40 years with Lycoming.

Q: Here is my mystery: I have a Geronimo Apache equipped with 0-360-A1As. The left engine is about 1,200 SMOH, the right engine is about 700 SMOH. They both had oil pressure of 85 psi in cruise and about 50 psi taxiing in after a flight. At about 1,150 SMOH, the LE began to show low oil pressure. It slowly, over about 20 hours, started dropping in cruise from about 85 psi to about 65 psi and down to 30-35 psi taxiing in. I thought bottom end bearings. [Read more…]

Tips to install an oil cooler

Paul McBride, an expert on engines, retired after almost 40 years with Lycoming.

Q: We have a Citabria 7ECA with a Lycoming O-235-C1 engine. We live in East Texas, where summers are very long and very hot. Even with an external oil filter with a blast air tube, the oil temps push 220°+ on normal altitude flights, even when babying the air speed and climb rate (which means that we need to climb to pattern altitude to get from cruise to landing configuration. Not really, but the old joke does illustrate the point.) We think we need an oil cooler.

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Ask Paul: What’s up with my oil temperature?

Paul McBride, an expert on engines, retired after almost 40 years with Lycoming.

Q: I’ve been having trouble with my Lycoming O-360-AIA engine for some time. The oil temperature is running about 200° on a cool day. The head temperature is in med green.

I have completed the following to determine the problem: A few months ago a new temperature control oil cooler by-pass unit was installed; and I checked the oil temperature probe by placing it in boiling water. The instrument in the aircraft read about 200°.

The oil cooler is a Positech with six tubes. The air source is an outside air inlet. I believe that the air flow is enough to cool the oil. I have no way to check. I have asked around the airport for help but this has not been fruitful.

GARY QUESTA, via e-mail

A: Gary, after reading your e-mail, I could hardly get the smile off my face. I don’t quite know how to tell you this, but most Lycoming engine operators would really like to have that kind of oil temperature on their engine.

Let’s look at some of the important things about oil temperature. [Read more…]