[Username Protected]

Is anybody using Evans waterless coolant in your engine? The Rotax site seems to HIGHLY recommend it and their description on its properties says that it becomes an even more effective coolant if it ever reaches its boiling point.


Even with Icon's recommendations on how to keep the engine cool I am always concerned about overheating this engine - especially when waiting for takeoff at a busy runway. Running the cockpit heater to pull off any engine heat possible is never fun when it's already hot outside.

[Username Protected]

Yeah it does get hot holding short with the heater on.

[Username Protected]

My 100hrs is coming-up in 2 months. I will ask Jimmy, my A&P about it! I have never had mine get hot while holding but I do not live in FL or TX like many of you guys.

[Username Protected]

This may sound counter intuitive but if you are starting to overheat while waiting rev up the engine between 3000-4000 or so and turn on the heater to cool it. The 3200-3500 is a where the fixed cooling fan on the prop is most effective at drawing air through the cowling at a low enough power setting that doesn't add much heat to the engine. I have found that running the engine up to those power settings is more effective than the heater. Both are the best combo. You can last a long time at very hot conditions if you do this. I did A LOT of testing on this.

[Username Protected]

Do a lot of you have overheating issues? My A5 normally stays on the low end of the green and if it’s cooler outside, it barely gets to the green. I have been flying it in 90-100 degree dry AZ weather with no heat issues. Makes me wonder if my gauge is off ?

[Username Protected]

Yours sounds completely normal. It’s not a problem if you’re flying (moving air across the cooler) it’s extended time 10+ min on the ground idling or taxing slowly when it’s above 80 deg outside.

[Username Protected]

Thank you Bret. That makes sense as luckily I fly out of an airport with zero wait time on the ground.

[Username Protected]

Yeah I don't have any issues in the air - only on the ground (or water).

In addition to waiting in line for take off there was one instance where I had to water-taxi for an extended time, downwind, in a no-wake zone. Each time I increased the RPMs for cooling I started throwing up significant wake - and the shore was lined with gawkers. I finally just shut her down and let it sit and cool off.