What deck do you have on that 3400. ??
Here is a parts break down, you may be able to spot the belt routing from the parts illustration ... if not I can fins a belt routing picture... :smile:KennyV
Oops... I didn't get the link attached.... Mower Manuals
In this group di=own to older models, in the 4000 series, the out front decks are listed... :smile:KennyV