Hi Oliver not sure if it’s relevant but we had a similar problem on a vadersrad drill when we ran it on a Fendt or CATHi. We have just bought a gd 4800m and mounted it on a mf 8480 we are having a issue with the hyd fan it fluctuates a good 200-300 rpm when we slow the flow of oil below 50% on the tractor it runs fine above 50% but to fast. I have had flow set at 43% and lifted drill up and down a good few time which settle the fan down and ran a constant 4800 rpm but not been able to do this again. Any ideas? Thanks
The fan was constantly hunting and wouldn’t settle
It’s a common problem and the solution is to fit a needle valve in the pressure line and bleed a small amount of oil into the return line
Dan