Hydraulic filter gauge and filter change schedule

[Groo]

I have a portable sawmill that has a hydraulic filter gauge, but the manual lists change the filter at so many hours (50, then again at 250 with a fluid change and again filter and fluid every 250 hrs after).

Is there a reason to change the filter based on hours if it is not excessively obstructive yet?
250 hrs seams like a pretty short lifespan for hydraulic fluid too. I've never seen the temp gauge on the storage tank ever go much above 100F, so its not like its getting cooked.

 

[CJONE]

The cheap hydraulic fluid is rated a 2000 hours. If you are using it in a very dirty location then I would change it 1 time a year or normally 1500 hours. Keep the filter changed, do it before the indicator says to. If it gets plugged the bypass opens and bypasses dirty fluid. The fluid does not wear out, it looses it's additive package and gets dirty. I have fluids here that is rated to 12000 hours and with offline filtration and additive samples and replacement it can last indefinatly. 1 customers crane is at 22 years with no fluid change. Just filtration [3 micron] and additive replenishment. Check you micron rating on the filter. Most are 25, I use a 10 and monitor the indicator. Once the fluid is clean it should run a long time unless you have a failure. Be sure you have a filter on the tank vent/fill. CJ

 

[Groo]

mine (factory and the replacement I picked up) are 10 micron too. Based on the engine air filter, it has been very clean. The only dust is sawdust, and most of that is directed away. I haven't seen the filter gauge get anywhere close to the change reading.

 

[CJONE]

mine (factory and the replacement I picked up) are 10 micron too. Based on the engine air filter, it has been very clean. The only dust is sawdust, and most of that is directed away. I haven't seen the filter gauge get anywhere close to the change reading.

Then you are like the majority of my customers, filter once a year or 1000-1500 hours and oil sampling. Change oil at the oil manufactures specs. The vent filter is key, keep the crap out of the system and you are good. CJ