955l cat clunking sound from hydraulic tank

[fest777]

i have a 85j7794, its making a clunk sound from hyd. tank ,noise stops when raising or lowering bucket,almost sounds like a valve in tank is the culprit . could it be air trapped in system, just recently lost about 15 gallons hyd. fluid from steel line rupturing, repaired line and refilled when noise started , its very noticeable , thought it was trans at first but could feel it threw the up/down handle, fest

 

[361brock]

Try raising the bucket all the way up, then open the hydraulic tank filler cap, then dump the bucket slowly till hit stops, then roll it back all the way, now slowly lower the raised bucket to the ground while watching the open fill cap, looking for spitting air and some oil, step out and check the sight gauge on tank see where oil level is, continue to lower bucket to ground. Now check level again in sight gauge, if low fill if to much let it come out. Replace cap and cycle hydraulics see if improved.