Watercooling a Novak Explorer II ESC ???

[Jamesbon]

I have a Novak Explorer II that quits after a couple minutes of hard running in my 6 cell rigger running a 15T D4. I believe it's due to the thermal overload protector. Once she cools a minute, she momentarily turns on again.

The heat sinks pop right off exposing two banks of three metal tabs. Can I solder a separate brass tube to each of the two banks and run water through? Apparently, the two banks will short of connected directly, hence a separate tube for each. My Explorer II looks like this

View attachment 1262

 

[Propjockey]

Doubt you would be able to solder brass to it...the cooling fins are aluminum.

If there is enough 'meat' on the fins, you might try flattening a piece of tubing just enough to push down between the fins.

 

[Andrewg]

that esc is designed for cars which draw far less current

it is overheating because the 15 turn draws current contiunously in a boat rather than intermittently as it would in a car

drill the heat sinks put a short piece of tight fitting aluminium tube thru each bank of fins and join the two with silicon tubing use computer heat sink compund to increase heat ransfer

this is risky if that controller smells water it may die.

The real solution lies in a boat esc like an rc hydros

 

[Jamesbon]

Thanks for the response fellas!! Taking the advice from both of you, I will drill holes through the purple removeble heat sinks, then slip a brass tube through each of them and connect with fuel tube in the center. This way, all I have to do is order new heat sinks to return the ESC to factory condition. (the purple heat sinks simply slip on and off)

Hopefully this will work. If not, I'll order a SC8 from Rum Runner and Ultimate BEC from Hobby Lobby.

Thanks again for your input!!!

Dad always said "two minds are better than one."

 

[DJT]

Won't the water flowing between the two heatsinks act like a single tube and short the speed control out?

 

[Jamesbon]

DJT,

I wondered the same thing......

Anyone...???

 

[forresterace]

No, the water will not short the fets out. In this case water is not nearly a good enough conductor of electricity to do any harm. The two brushes on brushed motors are connected in this same manner with water-filled silicon tubing for water cooling.

 

[Propjockey]

In this case water is not nearly a good enough conductor of electricity to do any harm.

Actually, absolutely pure water is an electrical insulator. The impurities in water, ie salt, trace minerals and metals etc, are what renders it conductive.

Propjockey Racing.....now testing conductive insulators. :blink:

 

[Jamesbon]

Well, it worked. I finally ran the rigger through a 6 cell pack without the thermal overload kicking in. As stated before, I drilled the purple heat sinks, ran 1 piece of brass tube through each set of fins and connected them in the middle with fuel tube.

I think I need to push the rear of the front sponsons down a little, the rear sponson tubes push a lot of water as she's coming up on plane. In fact, she only likes to run wide open. Any less throttle and the the spray/drag increase considerably. Will also try the slightly smaller octura X435.

...dying to post pics, but the Gulf of Mexico claimed my last digi. cam, and my first Olympus digi bit the dust.....gimme a few weeks...

 

[Jamesbon]

...Update...

Lowering the front sponsons helped as did the X435 prop. She close to being dialed in now.

After an early morning run today, I noticed the insulation on the positive wire between the ESC and motor was slightly distorted from overheating. My bullet connectors are tight as is the solder joint on the motor. I'm thinking of de-soldering the factory wires from the ESC and soldering on the next biggest guage wire. Any thoughts?

 

[Propjockey]

Sounds like a plan, if done carefully. 12 ga. would probably do the trick. While you're soldering, get rid of the bullet connectors. Use something like Dean's or Astro connectors, or eliminate them altogether and wire the motor direct.

Also, remember to keep the wires as short as possible.