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New: Rotax/Sonex Cooling Kits Available!

PostPosted: Fri Jul 12, 2024 12:38 am
by Skippydiesel
The new system looks great BUT seems only to address half (Coolant) the liquid cooling requirement.

Where is the oil cooler? - hidden in the ducting? or somewhere else entirely?

Re: New: Rotax/Sonex Cooling Kits Available!

PostPosted: Fri Jul 12, 2024 1:07 am
by Murray Parr
The oil cooler looks to be in front of the coolant radiator, I wonder if you could put the oil cooler behind instead. My oil takes forever to heat up enough for takeoff but the coolant quickly overheats and could possibly help speed up warming the oil. Maybe they tested this already or maybe not.

Re: New: Rotax/Sonex Cooling Kits Available!

PostPosted: Fri Jul 12, 2024 3:55 am
by Skippydiesel
Ahhh I should have looked further at the additional photos.

Oil cooler appears to be where you found it. It wouldn't be hard to fit a small, pilot condoled, flap/shutter to the exit air - that would certainly speed the warm up.

Re: New: Rotax/Sonex Cooling Kits Available!

PostPosted: Fri Jul 12, 2024 11:36 am
by ampzapper
Their full install kit includes an oil thermostat. That could help with warmup.

Re: New: Rotax/Sonex Cooling Kits Available!

PostPosted: Fri Jul 12, 2024 6:10 pm
by Skippydiesel
ampzapper wrote:Their full install kit includes an oil thermostat. That could help with warmup.

While I can see the potential benefit in an oil thermostat, in particularly cold climate. They add significant weight & complexity, to the oil reticulation system, as such should be avoided.

Re: New: Rotax/Sonex Cooling Kits Available!

PostPosted: Sat Jul 13, 2024 1:02 am
by CaseyCooper
Hello folks,

The cooling assembly houses both the oil cooler and radiator. The thermostat opens at 180f and weighs about 8 ounces. When warming up my engine, whether summer or winter, it takes exactly 5 minutes on the dot to achieve operating temperature. With a peak oil pressure of 70 psi while the valve is restricted and bypassed (it allows 10% of the oil to flow through oil cooler until warmed up and the rest to flow through the engine normally) and a minimum oil pressure of 55 psi, the system works perfectly within Rotax's specifications. While you could add a manual baffle of some kind, a thermostat is automatic, recommended by Rotax, less complex, and the same weight if you were to design such an assembly. While flying just this evening with 105 degrees OAT, I was seeing max temps of 225 for CHT's and 210 OT. With hundreds of hours on this combination, I have complete faith in the system.

We're gearing up for our 4th trip to Airventure this year and looking forward to seeing everyone there!

PS: I hope you're enjoying building some time in your Waiex Murray! That thing looks wonderful!

Re: New: Rotax/Sonex Cooling Kits Available!

PostPosted: Sat Jul 13, 2024 2:33 am
by Skippydiesel
Hi Cadey,

"...........a thermostat is automatic, recommended by Rotax,"

Please give me the Rotax manual/chapter/page where Rotax recomend the installation of an oil thermostat?

Re: New: Rotax/Sonex Cooling Kits Available!

PostPosted: Sat Jul 13, 2024 2:34 am
by Skippydiesel
Hi Casey,

"...........a thermostat is automatic, recommended by Rotax,"

Please give me the Rotax manual/chapter/page where Rotax recomend the installation of an oil thermostat?

Re: New: Rotax/Sonex Cooling Kits Available!

PostPosted: Sat Jul 13, 2024 3:38 am
by sonex892.
Skippydiesel wrote:Hi Casey,

"...........a thermostat is automatic, recommended by Rotax,"

Please give me the Rotax manual/chapter/page where Rotax recomend the installation of an oil thermostat?


I found it recommended in the 214 page rotax install manual. Its at page 184.

I'm going through all this at the moment trying to fit radiator, oil cooler etc in a sonerai.

Re: New: Rotax/Sonex Cooling Kits Available!

PostPosted: Sat Jul 13, 2024 1:44 pm
by CaseyCooper
Skippy,

Steve beat me to it! There’s some fine print to it but SL912-011 will help clear things up.

Steve! A Rotax powered Sonerai is going to be a blast. I can’t wait to see how your project progresses.