Tractor Repair: 1086 ta, cable clamp, accurate diagnosis

Question
just put a ta in a 1086 ,high side was out. also replace pump, filter, and went through mcv valve. now when you are below 1400 rpm and have steering turned all the way, ta shifts from high side to low side.

Answer
  The steering, brakes, and TA get their oil from the same pump.  There is either low flow from the pump or there is a leak that is taking too much oil away from the high TA clutch.  Since steering gets priority over the other functions, the steering will take all the oil if there is low flow or a leak.  Make sure the oil is not getting air in it from a suction leak which would make the oil foamy after running it.  If it is, check the o-ring on the filter cover.  I assume all gaskets and o-rings were replaced when the mcv was put back together.  The plastic sump check valve and spring between the mcv and transmission housing must be in perfect condition.  The pressures should be checked with a gauge to do an accurate diagnosis.  Make sure the cable is adjusted properly so that the TA shift spool has the proper amount of travel when the lever is moved in hi and lo.  An incorrect adjustment or loose cable clamp can cause some weird symptoms.  Also make sure the dump valve is adjusted properly so that when the TA is in hi, it engages just before the main clutch engages as you let out the pedal.  There is also an o-ring in the suction tube between the speed transmission housing and the rear frame.  If it is missing or damaged, it will cause a suction leak.