300E Blower Motore problem, please help
 

Hi i have a 91 300E 160 000 Km on it, the problem is that i melted the blower motor fuse on a hot summer day and replaced it with a Hd 30amp fuse and when i wired it and tested it, it worked fine. However now its winter and the motor only works when it wants to. Itll kick on for a few seconds and then shut off, sometimes never returning and its freezing out. Any suggestions would be helpful please thank you