Hose from water Pump

The hose from the water pump to the bottom of the number #2 cylinder is 17mm. In France you may have that size, but there is no USA equivalent. You can use some fire sleeve to wrap around an area that may be too close to an exhaust pipe to help protect it. 

USA hose is either too big or too small so anyone in the US should be getting the 17mm from a Rotax Service center.

Thanks for your reply Roger!

I think that indeed, the wisest thing is to go through a Rotax distribution center 

but for teaching, this hose is the same as the one used in cars? I assume so, but is that correct?

Jacques

The coolant will be changed of course, but should the circuit be rinsed with water before filling with the new coolant ? ( LR 35 Yacco blue )

My Evektor Eurostar is doing well, I wish it was still the case ?

Because Rotax had this hose made for them I doubt it’s the same exact hose as in your car. Will your auto hose work? I’m not sure. Maybe since others in the world may have a hard time getting the Rotax 17mm, but I don’t know that for sure. I’d still stick with the Rotax 17mm hose. I have never deviated from this especially when changing something like this can make you liable. 
As far as the coolant goes. Remove the bottom hose of the radiator and let the coolant drain into a big pan. Then remove the expansion tank cap and more coolant will drain. Then I put drape a rag over the coolant opening and the hose and then cup my had over the expansion tank opening and blow down through the system real hard four times. That pretty much evacuates all coolant. If you want and have access to the water pump you can remove that bottom screw and let it drain. Many times I can’t get to this screw due to the aircraft engine mounting position. Then replace the hose and refill the system. I use Dex Cool 50/50 (orange extended life) here in the USA.

Thank you Roger, I am always interested in hearing your opinion, which I consider very reliable and full of experience.

when I fly with my new hose, I will think of you!

Thank you

Jacques