Is a filter absolutely necessary for hydraulics?

[wdchyd]

I've thought about making up a test stand as I have several power units (variable flow/pressure) piston and vane pumps that would make a great power supply.....some good filtration (which is necessary for this type of hydraulics) and digital instrumentation and some fabrication time (which takes away from tractor time)...but I didn't see the need to take away my energy from the existing stuff I already do....

Not enough time in the day.......:laughing:

 

[bironacad]

That implies it was a dumb or needless question.
There are likely many readers who learned something from this short discussion as a result of the OP question.
I think increasing knowledge to members is the real worth and value of the TBN forum.

Hey everyone has a bad day now and again, lol.:laughing:

 

[JFS2295]

Hummmm

<---------------

That little 1952 Allis HD-9B with over 10,000 hours does not have a filter in the hydraulics and still uses it's orginal pump and valves. Cylinders tend to get crewed and reworked over time from external contamination.

 

[David Devuono]

My own project is getting close to putting in hydraulc fluid. That is after I get the 28 separate hoses made up - ouch. What I am wondering is, how long should I let the thing run oil through the filter before operating any of the spool valves or motors for the first time? I have done some welding on the tanks so I know there will be some crude (coking?). I thought about using a tank strainer but it would restrict the flow down from 1.5 inch line to 3/4 NPT or something like that on the suction side. Should I change the filter after an initial run in.

 

[IceStationZebra]

Dave,

First, a trick I have used numerous times is to put a magnet in the reservoir to catch metal particles. Something about 1" x 2" works well.

Second, be aware that not operating the spool valves will not guarantee that they stay clean. There are a lot of nooks and crannies in there.

Third, if the tank is really dirty consider temporarily plumbing the pump outlet right into the filter and back to tank, this will keep the garbage out of your system. Of course you are still putting the crud through your pump. Also, be aware that gear pumps have a break in period and can produce small metal particles. As far as run time goes, you want to completely recirculate the oil several times. If the reservoir is on the larger side this may take awhile because some oil will stay in the corners.

As far as changing the filter goes, it can't hurt. Wait until you have purged all the lines and have gotten it good and hot. Make sure to cycle the cylinders several times to get all the 'dirty' oil back through the filter.

ISZ