Brush cutter will not stay engaged.

[Bobcat lover]

Hi. I have a 763 Bobcat with about 2500 hours on it. There have been previous owners. When I try to run a brush cutter attachment the only way I can cause it to run is to hold the paddle on the right control arm to the right with my thumb. Needless to say after about 30 minutes my thumb is about worn out from continuously holding the paddle in position. I think that a previous owner has rewired something somewhere on the machine that is affecting the aux. pump controls. When I activate the trigger on the right control arm the machine locks up and comes to an abrupt halt. I have tried all combinations of engaging the green aux pump lights to try to get the cutter to stay engaged without holding the paddle to the right. Does anyone have any suggestion as to what I may be doing wrong? Is there a sequence that I am not following properly? The Bobcat dealer has been no help.

 

[ddbackhoe]

Push the aux. hyd. Button twice, then squeeze the trigger once.
Controls on Bobcat 763 and Planting Gold Mop Chamaecyparis 3.� - YouTube