Pre-pump oil filter....

[mrcaptainbob]

So all of my hydraulic equipment has a filter on it. And always on the return side. I understand the low pressure issue. But...what about protecting the pump? There was a gravity fed oil filter on my old log splitter that I do plan to install on the new one. But how about the other stuff? Will the standard oil filter work in a gravity situation? Along with the suction of the pump? I want to protect the pump as much as possible.

 

[mrmikey]

Most times a suction strainer is coarser to prevent cavitation caused by plugging so I'd make sure wahtever filter I use is made for suction. IMHO I don't like them at all but to each his own
The couple of splitters I've made I always make sure the oil pickup is raised above the bottom of the tank by an inch or so.....Mike

 

[J_J]

So all of my hydraulic equipment has a filter on it. And always on the return side. I understand the low pressure issue. But...what about protecting the pump? There was a gravity fed oil filter on my old log splitter that I do plan to install on the new one. But how about the other stuff? Will the standard oil filter work in a gravity situation? Along with the suction of the pump? I want to protect the pump as much as possible.

What do you mean by gravity fed? The fluid is either sucked through a filter or pushed through a filter. Now, you could call the tank filter gravity fed as you add fluid.

I believe hydrostatic transmissions are the only hyd components that use a hyd input filter, right before the charge pump.

The theory is that if the tank fluid is clean, via the return filter, that is good enough.

If a suction filter clogs up and has no bypass, bad things will happen to the pump. If the input filter has a bypass, and clogs up, then it will pass any anything in the fluid to the pump, and hydrostatic transmission in particular need very clean fluid.

 

[AKKAMAAN]

So all of my hydraulic equipment has a filter on it. And always on the return side. I understand the low pressure issue. But...what about protecting the pump? There was a gravity fed oil filter on my old log splitter that I do plan to install on the new one. But how about the other stuff? Will the standard oil filter work in a gravity situation? Along with the suction of the pump? I want to protect the pump as much as possible.

What is it that you think you understand about the "the low pressure issue...."??

Are you planning to use "the standard oil filter" as a suction filter?? It will not work on the suction side!!


Why would there be anything damaging for the pump in the reservoir, if all return oil from the system is filtered in a return filter??

Answer 1: You re-fill contaminated oil into the reservoir.
Solution 1: Re-Fill oil through a fill cap screen filter.

Answer 2: Contaminants enter the reservoir through the air vent.
Solution 2: Use an appropriate sized air breather filter

All hydraulic systems use a 14.7 psi charge system. That is the atmospheric pressure. To prevent pump from cavitation, this pressure needs to be available at the pump inlet port with a minimum of reduction. Suction head can increase that pressure, with about 0.5 psi per foot of head. A suction filter will reduce that pressure with 2-5+ psi depending on current pump speed/rpm and oil viscosity. Pressure reduction can be even bigger if oil viscosity is increased from very low temperature. So, as you can see or figure out, using head (gravity) as an argument on normally designed a log splitter, is not worth a lot. Note that gravity feeding a suction filter is not worth anything, if pump is not on the same level or lower, as the suction filter.

Water and air is the most common contaminants in oil. Water enters system as condense in the air and some times with re-fill oil. Air enters the reservoir when cylinder extends, and leaves the reservoir when cylinder retracts, The displaced air volume is the same as the volume of the piston rod.
Ice crystals in oil will clog the suction filter, with severe consequences for the pump

 

[mrcaptainbob]

I'm limited in my hydraulic knowledge. What I meant by the issue of 'low' pressure for an oil filter was that it should never be placed in a high pressure line. That is to say, it can have high pressure on one side, but allow to expel free to atmosphere pressure on the outlet side...back into the tank. My situation on the fel on my gt is that the oil reservoir is merely the left hand upright, a 2.5x2.5 box filled to about a 2.5 foot level. It gets hot. Not a lot of reserve capacity I suspect. I want to up that size as well as provide a larger fill port rather than the 1/4" pipe fitting presently available. So...I want to add a new port, and add more capacity. Doing so will probably contaminate the existing reservoir. The construction is such that I can drain the existing and, when finished, rinse it well. But I'm still concerned about any debris that can get to the pump. The pump is actually lower than the bottom of the tank. I'd like to install some sort of in-line safety, similar to my old log splitter. The pump is higher than the tank, but the filter is mounted to the bottom of the pump. I thought that was a good idea and would like it on the fel, too. I guess that's not necessary though? I really appreciate the help you all are giving me. Thanks...

 

[J_J]

Just let all hyd fluid run through a return filter, which would be low pressure. Install the return filter in a convenient area.

 

[GLyford]

My situation on the fel on my gt is that the oil reservoir is merely the left hand upright, a 2.5x2.5 box filled to about a 2.5 foot level. It gets hot. Not a lot of reserve capacity I suspect.

It might be much simpler to add a hydraulic cooler in the return line. As long as you have enough fluid to actuate all your cylinders, your real issue here is just the heat, right? Have you actually measured the temperature and checked it against your manual to see if it's running too warm (not just to the touch)?

This approach has been used on a lot of tractors over the years, should be a bunch of different cooler configurations on ebay to pick from. Some mount in front/above of the cooling air intake of the engine, or if water cooled in front of the radiator.

Though that wouldn't address your filler size issue...

 

[jonyyuma]

You could mount a finned oil filter adapter to help remove heat from the oil....or a heat exchanger that is coolant supplied.. I opted for the 10 micron prince filter and put it behind the seat for my return line from the fel controller..then put a line back to tank...