working on Lego Technic; Recovery truck. Reached Step 27(book 1)....fixing the rope spool. and found that the white gear wheel is not fitting in. i.e., i have the white gear fixed on the shaft with the spool, but when i try to fit it on the frame, it does not fit in, if i force it in, it goes on a angle. have relooked at the previous steps and can't see any part missed out or put in wrongly.
Any ideas what i am doing wrong? isn't the white gear wheel supposed to align with the small black gear wheel?