Suction Side Hydraulic Filter

   / Suction Side Hydraulic Filter #1  

dieselscout80

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New Holland TC45DA
I bought a new hydraulic pump for my IH 424 tractor. IH did not put a filter on the 424 rather just a metal mesh strainer. I want to protect my new pump with a filter, but Surplus Center suction filters are either 9 gal per minute or 25 gal per minute my tractor pump is 10 gal per minute.

The 9 gal ones have .75" fittings where the 25 gal ones have 1.25".

Should I get the 25 gal or 9 gal?
 
   / Suction Side Hydraulic Filter #2  
Since there was no filter to start with surly the 9GPM is better than none and it fits, besides the mesh will take care of any big stuff.
Also .75 fittings is probably a closer match for your system.
Worst case, change filter at say, every 500 hrs.
 
   / Suction Side Hydraulic Filter #3  
IH has only a suction strainer for a reason. Suction filter restriction with cold oil can harm a pump. Also if only a suction filter is used, it cannot have the same filtration capability as a pressure filter. Recommended design guideline is to have a pressure filter downstream that will clean the circuit to a finer level.

My Kubota CUT is an example of a tractor with a suction filter; however, the filtration level of that suction filter is not capable of meeting the requirements if the hydrostatic transmission. Therefore an additional filter is required after the hydro charge pump and before any of the rest of the hydro circuit.

Wanting a suction filter for your tractor, I suggest the larger one. I believe your tractor has a gear pump so it is pumping at max flow for the design speed at all times. You really want as little restriction as possible at all times.
 
   / Suction Side Hydraulic Filter #4  
Keep the strainer and go with a return filter, cavitation caused by a suction filter will take out a pump. A pressure filter is nice but expensive....Mike
 
   / Suction Side Hydraulic Filter #5  
Suction filters are necessary on hydrostatic transmission. Usually around 10 micron or smaller and changed often
 
   / Suction Side Hydraulic Filter
  • Thread Starter
#6  
Suction filters are necessary on hydrostatic transmission. Usually around 10 micron or smaller and changed often

JJ, what I'm understanding from your statement is to not to add another filter is that correct?
 
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   / Suction Side Hydraulic Filter #8  
IH has only a suction strainer for a reason. Suction filter restriction with cold oil can harm a pump. Also if only a suction filter is used, it cannot have the same filtration capability as a pressure filter. Recommended design guideline is to have a pressure filter downstream that will clean the circuit to a finer level.

My Kubota CUT is an example of a tractor with a suction filter; however, the filtration level of that suction filter is not capable of meeting the requirements if the hydrostatic transmission. Therefore an additional filter is required after the hydro charge pump and before any of the rest of the hydro circuit.

Wanting a suction filter for your tractor, I suggest the larger one. I believe your tractor has a gear pump so it is pumping at max flow for the design speed at all times. You really want as little restriction as possible at all times.


I tend to disagree about the suction filter. It is there for a reason and that is to keep the hydro clean as possible.

I also disagree about the suction filter to filter as good as a pressure filter if they are both 10 micron.

My closed center hyd hydro system uses a 10 micron filter and has been using one since about the mid 90's. Of course I change them often.

It doesn't make any difference about the size of filter as long as it is equal to or larger. Tractors with gear transmissions, use return filter.
 
   / Suction Side Hydraulic Filter #9  
JJ, what I'm understanding from your statement is to not to add another filter is that correct?


You can add all the filters you want.

Some hyd system choose to add large micron filter directly in the tank.

Other hyd systems only use a suction filter especially for hydrostatic transmission,

Other hyd system only use a return filter thinking that the fluid in the tank is now filtered.
 
 
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