Myford super 7 tripping RCD

Hi, I’m the new proud owner of a Myford super 7. It worked fine when I bought it but trips the house RCD everytime I select forward or reverse on the Dewhurst switch. I have rewired and cleaned the Dewhurst. Any ideas?

Cheers Nick

Hi, First post on here. Have you had a look at the capacitors on the motor? If they are failing, there will be a higher start up load which will do what you describe