Hydraulic fan system

[Keith Moffett]

Just a heads up on some info I got today;

Some time ago I had a hydraulic hose start weeping through the hose.  When Pirteq replaced the hose they installed a new HD hydraulic filter for me as well.  The original filter was about half the size and I reasoned the old fluid could be better filtered.
Looking now to replace that filter and flush the hydraulic fluid I began looking for Texaco "Rando 46" which is now a Chevron product.
Chevron informed me the filter must not be finer than 15 microns.  The new HD Wix filter I used filters to 7 microns.  The tech at Chevron said this will also filter out additives needed in the fluid.

[Lee Welbanks]

Keith, I have looked all over Chevron's Rondo 46 oil to try and find where it states what size filter to run, came up with nothing yet. Still looking.

[Keith Moffett]

Lee, I actually called and spoke with their 'lubricant specialist'.   So now can the 'experts' be wrong?  You bet they can and often are.  I dont have the definative answer but at 7 microns that filter can become plugged IMHO so off it comes first chance.
How often do you change your hydraulic fluid?  I see folks with huge repair bills and I cringe so I am going the extra mile now.

[David T. Richelderfer]

Keith - How long has the 7 micron filter been in place?  If you're going to change out the 7 micron filter to be safe, then shouldn't you also change the oil?  By now the "additives needed in the fluid" may have been filtered out and are all instilled the 7 micron filter, eh?  Or, can the additives be replaced from a bottle?

[Keith Moffett]

David, that is a good question.  The filter has been on for just over 3 years (15 K miles) now but I have no idea how old the fluid was when it was changed.
 I note now that there is pressure on the filter gasket causing a little seepage so I planned to change it and was looking into getting enough hydraulic fluid to change most of that too. 
The hose I lost 3 years ago in New Mexico made me wonder about the cause and I had assumed there was back pressure from a bad filter.  Fluid in the tank was dark as well.   That hose is a low pressure hose leading back to the filter and then the tank but it had seepage through the sidewall of the hose.  Had to nurse it from Lordsburg to Tucson to get it fixed.

[Don and Kathy DuCharme]

Keith, we recently blew the hydraulic line for the power steering. Since we lost most of the oil, it was a good time to replace the filters. I found that there are 3 filters inside the reservoir "tank" in addition to the in-line filter. The filters in the tank are FleetGuard, available from Cummins. If your system is similar to ours the capacity of the system is 34 quarts.

[Keith Moffett]

Don, sorry you had that happen.  I believe the hydraulic system is intwo circuits.  The steering side is a branch and goes away from the engine and returns to 'T' in again . 
Trying to remember a conversation with Ty, I seem to recall the fires start when hydraulic fluid hits the engine.  So glad that did not happen to you.