Draining hydraulics

[Iceman47012]

Have a question regarding a post that I read where the person stated that they drained the system and then filled it with kerosene and operated 3ph and steering for a few minutes to clear all sludge, then redrained the system. My question is has anyone else ever done this and if so how do you get all of the kerosene out of your hoses, cylinders etc

 

[ptsg]

I've used just diesel in the past on older tractors, mainly without wet brakes or wet clutches. Not exactly sure what the effect would be on the wet brakes or clutches.

Just drove it around a little bit, cycle all the hydraulics, putting as little load as possible and drain it all out. Won't remove all the sludge but will take a big part of it out. It also works good when the hydraulic system is contaminated with water.

 

[Iceman47012]

I'm assuming that my system has had water in the system based on the color of the oil thats in it, its a rust or caramel color.

 

[RodRocket]

I do not recommend using anything but the same type of oil that the machine is designed to use. However, using a very thin (low viscosity) oil of the same type, as a flushing medium, would be ok.
The main issue is seal compatibility. Most O-rings are compatible with hydrocarbon oils, etc. But sometimes O-rings can soften or swell or extrude due to the additives of non-recommended oils/fluids.
The real solution for clean hydraulic oil is good regular filtration, recommended oil changes and periodically draining the reservoir of the bad stuff. Simple really.
Water in the oil is commonly due to condensation forming inside the reservoir over night when the air in the reservoir cools right down. Getting the oil nice and hot next day usually boils the water off, but not always. Big changes in reservoir volume, especially with SA cylinders, means big amounts of humid air moving in and out of the air breather. We know humid air can hold lots of water, like a thunder storm.