Noisy capstan? tascam 488

[Will25]

Hi, I've just refitted the capstan belt on my Tascam 488 but it seems to whirr more noisily than usually when I put a cassette in...is this a common problem when refitting belts and is there a solution? thanks

EDIT dropped some silicone grease onto the capstan shaft, left a cassette in there for an hour, wiped off excess grease - is now silent 8)