Lets start with what I've done.
I got bored with rc cars, so i took an old radio shack boat and put my high performance rc car parts in it. The motor connects to the drive shaft through 2 metal gears (both 19 tooth pinions). The motor is an Orion Revolution 13 turn i think, and the speed control is a super rooster (I know nothings water proof).

The problem.
Whenever I set the boat in water it goes wild. I believe the motor is uninsulated, and it short circuits to the water, and causes the speed control to glitch. I checked the motor with a volt meter, and it has high resistance but still will allow power to flow. Any suggestions on how to fix this would be great.

I can get pictures if you need them.

The motor should be grounded, that is not your problem. Use your words and describe exactly what "goes wild" means. Do you have any throttle control at all, or does the motor just turn on whenever you place the boat in the water? Does the boat run but with a stuttering action? Does it die when you give it full throttle? What happens when you run the boat at part throttle? What/how many cells are you using? What charger are you using? You have to help us help you.


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What i mean by "goes wild" is i have no control of the throttle. The boat goes full throttle, stops, full throttle, stops, and so on. Its not always a perfect pattern though. Sometimes it remains under my control for a few seconds, but then i lose control of it as soon as I touch the throttle. When it is out of the water it works fine, but as soon as the prop touches the water it has a mind of its own, and i cant control it.

The problem has to be either in the speed control or motor. I still have control of the rudder when I can't control the throttle.

Its only 6 cells, but its a really high powered, high efficiency brushed motor (stripped both of the gears while trying to figure out exactly what it was doing). The drive shaft is a solid piece of steel, and the prop is some horrible radioshack plastic thing, only about 2 cm diameter.

Although the motor is grounded. It can sometimes have a lower resistance path to the water, so thats why i was thinking it was grounding to the water. I asked an electrical engineer and he said it was possible, so I don't know it should be excused as a cause.

I'm new to boats so I don't know what other information you need to help me. Sorry for any typos too :P