Thanks for the tips - I will try them as soon as I get a chance - most likely at the week end. I tried cleaning the filters ( a slight improvement ) and found a very small split in the pipe taking LHM from the reservoir to the pump. I cut out the bad section and reconnected the pipe (a bigger improvement) but the problem still continues - although at a much lesser level. I havent had a chance to drive it much so there may still be air in the system. So far I have been looking for problems with the hydraulic system as thats w what it felt like. There was definitly air getting into the system but there may be some wear in the mechanical parts as well making the problem worse- so thanks for the advice. Sillybilly