So I've reassembled the filters filled with fresh oil and it seems to have improved things about 20% It still takes time to get going but seems to be going better once on the move.

There was a filter bypass in the filter assembly and the filters were rather clogged so I think there is a chance that some of the swarf that I found in the filters may have got through the system. Could this have got to the pedals and blocked the flow of oil through the switches or to the inching valve or anywhere else for that matter?

I'm going to try to get hold of a pressure gauge to test the pressures at the inching valve are there any other areas I can test while I have it?

Thanks.