I recently bought a 2004 Case 130 and i had a new loader fitted ( Rossmore 105 ). It uses a Walvoil DLM 142 valvechest ( closed centered with load sensing). If i start the tractor and use the loader straight away, theres no problem, but if i first drive for 20-30 minutes and then use it, the leaver/valves stick. When its forced to work for a minute its fine again. I suspect that this is being caused by thermal shock, but the valve chest already has a bypass valve to help prevent this!!! The tractor hydraulics check out ok. The supplires will be taking it back to fix this but they have already admitted that they have never before seen this!!! Any ideas?
Problem solved, Suppliers fitted a different brand valve chest, NIMCO Controls, all ok now.