MP40w noise

[karncoco]

Is it normal for the MP40w to make WUCHING sound on the short pulse mode?

[EcoTech Marine]

Heh, it's a bit tough of course to express sound in words, but it should make a vrrm vrrm vrrm type of nice as it pulses. If the noise is high pitched and mechanical, it could be a bad bearing in the motor.