Passively watercooling the ESC

I have been successfully using a water cooling system without a pump for almost two seasons now with no issues at all. There is a 5mm water intake hole at the center front of the nose cone in which a 1/4" OD polyethylene is inserted from behind, which leads up the mast with the motor wires to the ESC. The dynamic pressure from the forward velocity is plenty to push the water all the way through the system when traveling fast enough to need it. I have the exit tube mounted where I can see the cooling flow when foiling, so I always know it’s working (you can also hear the cooling flow while foiling as it drops down to the surface). This system has never gotten clogged, blocked, or otherwise failed. If anyone is using a 70mm OD inrunner and wants the STL file for the nose cone containing the inlet feature, let me know.


Hey, that looks great, was looking exactly for a file like that. Is it compatible for gong foil mast?
Would love to get the file if possible.

Hey jnobile!

Would be great if you could send the STL file. IΒ΄m looking to build something simular.


Below is a link to the nosecone with water intake for ESC cooling (70mm dia, for 70mm dia innrunner; mates with previously posted motor mount)

I have no idea, but the mast it is designed for is ~132 x 16mm.

Hi @jnobile,
Is it possible to publish or send me the .step or Fusion 360 file, so I can adjust it to my foil?
Thank you!