Date: 201302
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Daylight
Aircraft: Light Sport Aircraft
Operator: Personal
Operating under: Part 91
Flight plan: VFR
Mission: Personal
Flight phase: Cruise
Airspace: Class E ZZZ
ATC / advisory: TRACON ZZZ
Aircraft component: Engine
Component problem: Malfunctioning
Reporter organization: Personal
Reporter function: Single Pilot; Pilot Flying
Reporter qualification: Flight Crew Commercial; Flight Crew Glider; Flight Crew Sport / Recreational; Flight Crew Private
Human factors: Confusion; Training / Qualification; Troubleshooting
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Other / Unknown
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Diverted; Flight Crew Landed As Precaution; General Maintenance Action
Contributing factors: Procedure; Aircraft; Human Factors
Primary problem: Ambiguous

Narrative: I have been making plans for the past year to fly through a canyon in my Light Sport airplane; a Rans S-12S. I would make the flight alone; since it was my first chance to fly the route.I took off and headed directly to a CTAF airport where I landed for fuel. I had gotten a weather briefing the night before and a Standard Briefing that morning. The weather looked excellent for my entire route of flight. I filed a flight plan and opened it when I took off. I also contacted Class D Approach for flight following.I landed (after contacting FSS and lengthening my flight time) and refueled. I had 18 gallons of fuel on board which was more than enough for at least 4 hours of flight time. I took off and flew across the mountains to the south entrance of the canyon. I climbed to approximately 10;000 FT so I could make contact with FSS and close my first flight plan and open the second leg. I then dropped back down into the canyon and flew from one end to the other. There were no indications of any engine problems at this time.When I got close to my en route stop I noticed some erratic movements of the CHT gauge. After landing I found that the wire leading to the sensor had broken off. The weather was good; I had plenty of daylight remaining; and I figured that the broken wire was the cause of the erratic movements of the CHT. There was no indication on the engine of any oil or coolant leakage. There was a bit of coolant on the horizontal stabilizer; but I attributed that to coolant being sucked out of the coolant overflow bottle; a problem which I have had before and my mechanic had checked out for me. As far as I could tell at that point the plane was safe to fly so I took off to head for my home airport.As I climbed over the mountains I noticed that the oil temperature gauge was giving me a high reading. I decided at that time that rather than continue on to my home airport I would land at a nearby airport where I had some friends who could look at the plane for me. After considering this though I thought it prudent to land a bit sooner so I contacted a nearby Class D Tower and told them 'I was having some engine problems' and would like to land. They apparently considered that to be an emergency and brought me right in.I again noticed the coolant on the horizontal stabilizer and some oil on the other side. There was no indication of oil or coolant leaking out of the engine so I assumed both were coming from the overflow tubes that emptied out at the bottom of the aircraft. I checked the oil level and found it to be full and noticed the coolant overflow bottle needed fluid; I filled that up as well.At this point I thought that I was having more problems with the gauges than anything else; and that possibly some air had gotten into the coolant system causing the higher than normal oil temperature. I had plenty of fuel and decided to continue the flight; under flight following; back to my home airport where I could have my mechanic check for the cause of the leakages. The engine also sounded normal and there was no abnormal vibration of any kind. I would be flying the entire distance over open farmlands with plenty of emergency landing opportunities should I need one. I elected to continue the flight home.When I got home we noticed that there was enough oil and coolant splattered on the horizontal stabilizer to warrant some investigation - which we did.




Synopsis: A RANS S-12S pilot continued a series of flights after detecting coolant on the horizontal stabilizer with the engine oil temperature running slightly higher than normal.