Harry Smith uses fan-equipped car ESCs in his models so there's clearly not a compatibility problem there. The ESC doesn't "know" whether a motor is an inrunner or outrunner – only whether or not it's fitted with sensors, and most aren't. If you do fit a car-type ESC then it may be necessary to disable the braking function, but that's a doddle if you use a programing card.
I would suggest that any motor/ESC combination should first be run on the water and checked for temperature before any consideration is given to cooling. In my own limited experience neither gets even remotely warm, let alone hot enough to warrant cooling.

Dave M

Derek
I've looked at the Hobbywing Quicrun website **LINK** and there's a picture of a car/truck chassis with an inrunner motor fitted alongside this particular ESC. It certainly appears to say "4 pole" on the side of the motor. The specs say only that it's compatible with "SL BL Motors" – presumably SensorLess BrushLess, so I'm none the wiser for that. All in all there seems to be something in what the guy said, and risking the thick end of fifty quid when you've been warned against it doesn't make a deal of sense to me!
If it were my decision I'd forget that particular fan-cooled ESC and go for a dedicated marine one, known to be compatible with 14 pole outrunners like the motor you propose and with the facility for water-cooling if it proves necessary. I've used the 30A V3 ESC from Component-Shop and so I'd have no hesitation in going for the 60A one for that motor. **LINK**

Dave M

Edited By Dave Milbourn on 12/09/2018 12:40:06

I used the 30 amp marine Esc and Leopard motor from Component Shop in my Pt Boat. Even after 30 – 40 mins at speed on 7.2 v and 8.4v neither was warm. I am using the same combo in a Fairey Huntsman and Italeri S100. I have used air cooling in my Model Slipway Tamar, I fitted a computer fan above each of the motors.

Tim