This month’s Ask a Tech inquiries come from a Cessna 172 owner who can’t seem to keep the engine’s oil temperature off the redline and a Mooney owner who got a letter from the FAA about altitude reporting problems. First, that hot-running Lycoming engine.
“I bought a Cessna 172M with a Lycoming 160-HP engine with under 300 hours SMOH. The problem is when the temperature goes above 70 degrees F, the engine oil temperature goes in the red after about 40 minutes in straight-and-level flight. The engine runs we’ll and there is no overheating smell that I can tell.