Q: I’ve been plagued with engine trouble on my Cherokee 140 for nearly three months now (O-320E2A). It began missing briefly every five seconds or so in-flight. After landing, we pulled the plugs and cleaned them. But it did no good, she still wasn’t happy.
Q: Can the Champion 37BY plug (either REM or RHM) be used on a Lycoming O-360 A1A engine? My concern is that the piston may hit the plug tip. Is this a valid concern?
DAVID M. GITELMAN, via email
In the July 5 print issue of General Aviation News, reader Dennis Reiley offered his thoughts in Letters to the Editor about my column, “Does my engine need an oil filter?”
Here’s a bit of what he had to say: “I have to disagree with Paul. Every internal combustion engine needs an oil filter — even those that have frequent oil changes. An oil filter can mean the difference between getting to your destination safely and experiencing a catastrophic engine failure.”
First, I wouldn’t say Dennis is disagreeing with me, because I understand exactly where he’s coming from. Besides that, I agree with him, but there are other factors that come into play as to whether an engine is equipped with a full flow oil filter or not.
Q: I have a 1998 Maule with an O-360 engine. I have the original needle oil temperature gauge, as well as a JPI-730 engine analyzer, and they both read the same temperature during all phases of flight.
My annual was completed a few days ago and the first thing I noticed was that the original oil temperature needle would initially fluctuate (never happened before) and then settle down, and when airborne it was at least 45° higher than the JPI-730.
I brought the plane back to the IA and he tightened the probe connection on the engine, but the temperature split is the same. Is the original oil temperature gauge adjustable?
ROBERT BLAKE, via email
Q: I just purchased a 1978 Citabria 7ECA with a Lycoming O-235-C1. Just had my first oil change done — it has no oil filter! Just one, maybe two, screens. Are these screens just as effective if I change my oil every 25 hours? Should I add an oil filter? Is that even possible? I run Phillips X/C and CamGuard. Your thoughts?
Jimmy Schramm, Tampa, Fla.
Q: When an engine with chromed cylinders comes into a shop with oil leaks and the source has been identified as thru bolts and cylinder base o-rings, how should the cylinder removal and reinstallation be handled? Also, is there any wisdom in turning the oil scraper ring upside down in chromed cylinder to help control oil consumption?
JAMES FINLAYSON, via email
Q: I work on a IO-360-MIA Lycoming engine. My problem is that the right mag has a drop of 220 rpm. I have done internal timings, engine to mag timings, ignition leads check and cleaned the plugs. I have done nothing to the left mag, and now the left mag is dropping to 210 rpm.
ANGI LISA CHAMBERS, via email
Q: I have been looking for a possible STC to install a primer system on a O-320-A2D. Would you know of one?
JERRY BARNHILL, Longville, La.
Q: I am doing a 100-hour inspection on a Piper Aztec with TSIO 540 Lycomings using Shell 15/50 oil with 50 hours on the oil. They are both midtime engines on this photo plane. They fly six hours a day at low power settings. The left engine oil is black like it should be after 50 hours. The right engine oil is a light creamy color. Something is not right.
Q: I recently installed a new three-blade propeller in my Comanche 250 with an O-540 engine. After the first flight I noticed a vibration when I decrease the rpm to 2400 or below, so I had the prop dynamically balanced. This did not change anything. The engine still vibrated.