pto gearbox
2) Loosen the bolts only when fitting the shafts. DO 
NOT take away the bolts totally. If taken out they may possibly fall into the housing and lead to a failure. The box need to be disassembled to retrieve the bolts if this takes place.
1) Tighten bolts to stay away 
Just take treatment when tightening the 4 x locking bolts inside of the housing. These bolts repair the detachable splined shafts in area.
Notice: When fitting splined shafts.
Simply click on drawing to enlarge.
pto gearbox details as well as pto gearbox misconceptions.