do they go down slowly as it sits turned off...... or while running? While turned off this is common. Also how slow is slowly? Over night? with in an hour or?
Be aware..... the zb1400 is possibly a Gray Market tractor. Least it is in USA. Maybe there in GB too. Does it have Japanese writing on labels or English?
Looks the ZB1400 pics I found seemed to look a lot like the B1400.. which is also Grey Market. See the two stickies at the top of the Grey Market Forum for more info