Makerbot Replicator 2 cant print for some odd reason

[CADstudent]

So ive been working on this printer for over a year and ive ran into yet another problem and this one i cant quite rap my head around how to fix it. So this is what its doing is either between prints (unsuccessful prints) or during long prints the filament sort of jams itself and the temporary solution is unload and reload filament but ive noticed a pattern of what the filament is doing it sort of bloats up from heating and stops itself from going through and with in seconds the drive gear just shreds and chips the filament making it unable to go through and you can see this from the photo this problem is just constantly occurring and it leaves prints a splotchy web mess( similar of what acceleration problems would do) or just stops altogether and air prints. I had a forum before on this issue but we concluded it was coding issue which now i notice it most definitely is not. Any help/input would be appreciated. ---DOWN WITH MAKERBOT!