I trust by this time everyone is enjoying the summer weather and getting the opportunity to do as much flying as possible. I thought this might be a good time to focus on a subject that everyone should keep in mind when it comes to seeking technical assistance on their aircraft engine. However, what I’m […]
Ask Paul
Is there a gentle way to determine the condition of this engine?
Q: Last year our club bought a PA-25 tow plane. It has a Lycoming O-540 G1A5 260-hp engine. We bought it with 100 hours after overhaul and flew it 95 hours, so total 195 hours after overhaul. Now the annual inspection revealed a massive contamination of the oil filter with shiny non-magnetic particles. Also some soft sealant particles (rubber or silicone) are […]
What is the proper procedure to break in my engine?
Q: What is the proper procedure to break in an IO-540-AB1A5 that I own on a 1998 C182S? We pulled and replaced the compression and oil control rings on cylinders 2 and 4. The rest of the cylinders were untouched. Where can I find Lycoming recommendations for a replacement of rings like we are about […]
Is this converted engine reliable?
Q: We recently bored a Lycoming 290-D2 engine to accept 320 cylinders (low compression) with 8.5:1 pistons. The engine has all new bearings and valves, and everything has been magnafluxed, balanced, etc. We retained a very good 290 D2 crankshaft. From experience, would you say it could make a reliable engine? Gilles St Pierre, AVIATION BSL (Canada) A: […]
Can I use these cylinders?
Q: I have several wide deck cylinders (for a Lycoming) 360 but the deck is a little bit thinner than normal and the deck looks like it is milled or radiused around the attach nuts area on the deck. I’m not sure where I got them from, but are they early style wide deck? Can I mix […]
Should we always rebuild at 2,000 hours?
If I did my math correctly, this engine has been operated approximately 38 hours, on average per year, during the 47 calendar years of its life.
Ask Paul: SI creates confusion about exhaust valve
Q: I recently purchased a high hour O-320-A1A in an RV-3. The rocker arms were out of limits and I had them rebushed and sized. The description for the exhaust valve is confusing on Lycoming Service Instruction No. 1451A. Under the cautionary note, the exhaust valve is “identified by the oil drain hole located under the valve […]
Tips to restart an idle airplane
Q: Because of medical problems, my IO-720 has not run in six months. While always hangared, the hangar is sometimes damp. The question is what to do in re-starting? Do we open it up and clean, or change the oil often? Larry Smith A: Larry, first of all, we certainly hope all of your medical issues are […]
Ask Paul: Wide vs. narrow deck engines
Q: Big picture question here: For a 250 or 260 hp Lycoming O (or IO)-540, is there any significant reason to favor a wide or a narrow deck engine? In particular, I’m looking at buying a core for a project and there seem to be more narrow deck cores available (presumably because their host aircraft are […]