Hi hows it going , ive just revived my first Cinquecento have a new engine in her and the car is just about finished but I cant get the back gearbox bolt back in. Its definitely the right size but yet it feels wrong when putting it in cause it just pulls back out . Has anybody had this problem before or know a solution for it ?

cheers

The back gearbox mount is held in by 2 bolts with captive nuts, however the main bolt going through the mount sandwiching it together has a nut on it. If you're talking about the big bolt it needs a nut...

in the past on previous engine mounts in that position, I have welded a nut on, and even used chemical metal to do the same to secure the nut in place, it helps a lot.