Tractor Repair: case 1370 field tractor, hyd, clutches

Question
hi there have problem with trans. no hyd. except when clutch pressed in or when tractor in 3rd range also have to increase rpm to get tractor to move in 3rd gear when unit warm, hyd. for front
end loaderalso won't work until clutch pressed in.
hope someone can offer a idea to help me

thanks al

Answer
  It sounds like you may have an internal leak in the C1 clutch.  C1 is not used when the pedal is down, or when in 3rd or reverse but is used in 1st and 2nd.  All the clutches should be pressure tested with gauges, and the pump should be checked with a flow rater.