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I need some Rotax advise as my plane is stranded at another airport.
The coolant overflow bottle failed in flight. The first sign was some red fluid in the cockpit a few minutes after take off. At first I thought it was brake fluid.
I noted the EGTs were high, but the CHTs were in range, and the oil temps were slightly high, but not in "the red zone"
A minute later I started smelling something in the cockpit and turned back to the field at reduced power.
A few minutes later I lost one of the CHT probes, but the other was reading fine. A few minutes after that I lost the other CHT probe. Oil temps at this point were still just into the yellow zone.
On the ground I pulled the cowling and found the coolant bottle had melted a hole at the point closest to the oil reservoir. The shrink wrap that holds the CHTS in place had melted and the CHT connectors had come out of position.
I was able to get some more DexCool and field replaced the coolant bottle with some attempts to heat shield it.
Runup and pre-flight were normal. The engine made normal power on take off. After climbing above the airport I noticed the CHTs were still high.
The engine was also only making 5100RPM in level flight with full throttle. I normally can exceed 5500 with my prop pitch.
I landed back and found a hangar to tuck it back in at.
So now the question is, what should I be looking for? The engine ran smooth. Shut down was brisk as always. Based on this I do not think one of the pistons is damaged.
The current plan is to compression test it, check the plugs and pull the oil filter to look for metal.
Does anyone else have any ideas?