Replacing crimp pins on Motor wires

Poor connections on the YL motor wire have caused the motor to judder and the connector to overheat. The heat has discoloured the pins coming out of the Duet and the Crimp Pins attached to the ends of the motor cables.

I intend to replace all of the crimp pins terminating all of the motor cables.

Can you recommend a crimping tool that's going to give me a good connection between the Crimp Pins and the exposed wire?

The crimper I have doesn't do the job and I'm not getting good results with long nosed pliers (I'm not good at soldering so would prefer not to do this unless I have to!).

Thanks