Q: I have a factory reman Lycoming O-540 E4B5 with 300 hours and 2.5 years on it. At idle (1,000 rpm), my JPI is showing alarms on the #1 EGT for having a large differential — #1 EGT is only 600° while the rest are 1,200-1,300°. Above 1,500 rpm and higher everything seems fine with […]
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The marriage between piston rings and cylinder wall
Getting back to the main point, if you don’t remove the piston from the cylinder, then you don’t have to worry about disturbing the marriage I spoke of, and honing and installing new rings is not required.
Ask Paul: What is the correct timing for my engine?
Q: I have a Lycoming IO-360-A1A on a Mooney E model. My mechanic tells me that there are two timing settings for this engine: 20° and 25° BTC. The engine had been set at 20° BTC and he reset it at 25° BTC. What are the advantages or disadvantages of this timing change? The engine […]
Will this replacement camshaft work in my engine?
Q: I have an O-290-D2 that I am going to use in an Experimental Wag Aero 2+2 that I am building. Although the engine was flying regularly before I removed it from a Pacer and pickled it, I want to open it up to look at the cam. If the cam is pitted, a replacement […]
Ask Paul: What causes this popping sound?
Q: I am test flying my new RV-9. It has a new Superior O-320, dual p-mags and an MTV11 2-blade MT prop. When it has been running at cruise power for a few minutes or more (say 2,300 rpm x 23 inches or more) and then I reduce the throttle, I get a popping/crackling sound […]
Ask Paul: What’s best? A flush or overhaul?
Q: I recently found paper towel bits and pieces in a Lycoming engine in an aerobatic airplane. The pilot said he saw the oil pressure go to “zero,” so he reduced power, and landed safely. Would you suggest a flush or overhaul? What’s the best way to go about this? ED NELSON, via email A: […]
Ask Paul: Why is my spark plug oil-fouled?
Q: I have been noticing an intermittent miss on the left mag during mag checks on the O-235L2C in my 1981 Cessna 152 (about 670 SMOH that included new Lycoming cylinders and pistons). About 30 hours ago when I cleaned, regapped, and rotated the plugs, I found that the lower plug on the #4 cylinder […]
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 […]
Ask Paul: What’s the proper procedure to cycle a prop?
Q: I’m curious about the procedure for cycling a constant speed propeller on run up. Three times seems to be a tradition, but I can’t find anything that supports this as a good habit. I’ve read that this was necessary with the big old props swung by a radial engine, but how about our newer, […]