Um, you really need to check the motor tag. The overload control exists to protect the motor from going up in smoke if it is...well...overloaded. I assume the "11" means that the overload control will pass up to 11 amps for an extended period of time. If your motor is rated for less than 11 amps, you risk overheating and destroying it. Even potentially causing a fire.
BTW, 11 amps at 230 volts is more than 1.5 horsepower for a typical AC induction motor. A motor could start pulling more than amps than it used to if, say, the motor bearings are shot. The extra draw would be because of increased friction. But there could be other problems, like poor connections* that were already pointed out, or even a combination of problems.
Craig
* The resulting arcing can also be a fire risk.