Cetop for a hydro winch

[Team Idris]

In theory you're no more at risk than you are lowering a bucket on a digger, but in reality these conveyer belt motors all seem to creep due to internal metal tolerance. If it gets full of gas, the gap is likely big enough to circulate between the components. The over-run valve stops any oil returning to the tank unless there is 20% pressure applied to the winch-out line. If there's pressure, then there's oil, and if there's oil, the motor can bite on it

Hydraulically speaking it's a cavitaion issue, so a 'make up valve' to break any suction would do the same job.

It is usually directly on top of the motor, where it also forms the job of anti burst valve. My typeR milemarker has it on a hose which seems daft.

If it's flat land winching it serves no purpose.

[Team Idris]

I was cleaning my teeth, before I go stuff more wires into my dash box, and I was thinking I'd pass on what seemed to be in my valve;

One way valve ( so it winches in without over-run valve action )

ARV ( auxiliary relief valve that protects the winch )

pilot operated valve ( that does the over-run bit and is linked into the ARV somehow )

I had no idea how much was going on in it until I read up and adjusted the external screw

[nickwilliams]

Your valve has closed A+B ports when in the centre position, so if the hydraulic motor on the winch is in reasonable condition and connected directly to the ports, simply closing the valve should provide a pretty effective brake to stop the winch unspooling under the weight of the load. Yes, it will creep if the winch is left loaded for any significant period, but if you are not doing anything too safety critical that probably won't matter.

At least that's the theory....

If you need the winch to hold the load reliably for safety (or other) reasons, it all gets a lot more complicated....