Hydraulic flush

[NHL455]

I went to change my hydraulic filters yesterday on 1988 L455 New Holland and found the fluid to be milky and white gunk in the middle of the filter so have to change 15 gallons of oil too. My question is there a way to flush hydraulic system before putting new oil in or does the small amount remaining not make a great difference as any mositure is diluted into the new oil? i know to close all cylinders etc to get as mucch old oil out s possible

 

[deaop06]

Water is not good for hydraulics. I don't know your setup but I will tell you what I did. My machine set for 6 years. I had water ( milky white ) bad. Got wheels off ground and hooked a hose to the auxiliary hydraulic out line. Started machine up (run at idle and let it get warm) and pumped the old fluid out until it started to spit. Then I refilled, changed filters and run at 1/3 throttle until warm. When I checked there was still some milky in fluid. Cleaned screen as it was full of curd. Then I done the same thing over again. Fluid looked good after that. I used it around 50 hours and when I checked the fluid still was good but screen needed cleaned. I clean screen every 50hrs and after 500 hrs of use screen was pretty clean. Not a cheap fix but it worked. I used the cheapest fluid I could find to flush as I needed 17 galleons each flush and two sets of filters. If you have good access to your tank you could clean by hand as much as you can. I don't know of any cleaner that could be used on hydraulics. Good luck.

 

[NHL455]

Water is not good for hydraulics. I don't know your setup but I will tell you what I did. My machine set for 6 years. I had water ( milky white ) bad. Got wheels off ground and hooked a hose to the auxiliary hydraulic out line. Started machine up (run at idle and let it get warm) and pumped the old fluid out until it started to spit. Then I refilled, changed filters and run at 1/3 throttle until warm. When I checked there was still some milky in fluid. Cleaned screen as it was full of curd. Then I done the same thing over again. Fluid looked good after that. I used it around 50 hours and when I checked the fluid still was good but screen needed cleaned. I clean screen every 50hrs and after 500 hrs of use screen was pretty clean. Not a cheap fix but it worked. I used the cheapest fluid I could find to flush as I needed 17 galleons each flush and two sets of filters. If you have good access to your tank you could clean by hand as much as you can. I don't know of any cleaner that could be used on hydraulics. Good luck.

sounds similar to mine which i believe hadnt been changed for 6 years although has only run 200 hours in that time. I had curd/cheese in my reusable filter and in the middle of the smaller disposable filter. I didnt want to run the engine as i wanted to keep the new filters clean (i was only intending to change the filters originally as have already spent too much money and the oil on the top was clear and clean) so i jacked up the back higher than the front and with some brute force managed to open both the drain plugs at the front one on each side and which luckily are about 60mm wide so let all the thick stuff out - i then put the drain plugs back in and refilled with some of the old cleaner oil off the top and let this soak through the tanks again. I also drained the main cylinder and i stuck a rag in the drain holes to get any remaining gunk out. I have ordered 60 litres of the cheapest correct grade SUTO oil which isnt cheap! confident i have got most of the oil out and any remaining should be well diluted with the new stuff! hopefully run it for a bit and then change the filters again in about 6 months as i dont use it very much in winter