# Where To Find Hydraulic Help?



## DustyTrails (Apr 22, 2017)

I am new to tractors and recently bought a 1979 Kubota L245DT with hydraulic problems. I question the hose connections on the FEL control valve. It is a single lever with four directions (up, down, scoop, & dump). I am looking for schematic diagrams of how to properly connect the hyd. lines, where to place a pressure gauge, how to adjust the hyd. pressure and flow, and where to place an after market hyd. filter Like the Filter Base WIX#24001 with a 141 micron screen WIX#51614. And I'm wondering if the add-on filter will require a by-pass valve (say 25psi?) or not. Any help will be greatly appreciated. Thank you, Dusty
//


----------



## RC Wells (Dec 26, 2008)

You really do not want an add on hydraulic filter on the loader circuit. The tractor has limited hydraulic capacity so relies on oil changes and the screen type filter to be cleaned.

The low pressure filter you are contemplating would have to be installed in a low pressure return line. 

If your tractor is having low or no hydraulic pressure, check the hydraulic relief valve mounted on the three point housing. They stick if routine fluid changes are not performed.

If that is not the problem, look at the line coming out of the bottom of the pump and going to the side of the three point housing. Loosen it and see if any fluid is coming from the pump. If not, go back to the pump and check the line on top, the suction line and see if it has oil to the pump.

No oil to the rear would indicate the pump is not turning. Gear could be loose on the pump or some other problem with the drive. 

If the pump is turning check the suction tube for a leak. It is possible the mounting or one of the connections is not holding vacuum enabling the pump to pull oil. The suction tube could be leaking where it has the fitting welded and pulling air so it will not prime.


----------



## Fedup (Feb 25, 2014)

I agree that an "add on" return filter will offer very little long term benefit and probably be more hindrance than help. 
As for your "questions" concerning hose connections or schematics -- most small tractors were not factory assembled with loaders. These were(and mostly still are) installed and plumbed by local dealers or in some cases at an assembly/distribution center AFTER the tractors arrive in this country. "Factory" loader hydraulic schematics for any tractors will be scarce if found at all. Yours may (or may not) still be set up the way it was when first delivered, or the loader was first installed. Whether it's correct or not depends on what style valve(s) it has, how exactly it's hooked into the tractor, and of course, whether things function as they should. 
Best place for a pressure gauge would be between the pump and the first valve in the series, if at all possible. As for adjustments, here again, that depends on what you're after. Pressure adjustments can be made when needed, but rate of flow adjustment is usually not possible. Since you have not mentioned any issues or symptoms, why are ANY adjustments necessary at this point?


----------



## DustyTrails (Apr 22, 2017)

RC and Fed, Thank you for your replies. I have cleaned the hydraulic screen once a month for the last three months (after having to drain almost 10 gal. of hydro-gear oil each time - a royal pain in the pin feathers). I just got this tractor and it seems to be in good shape (for being 30-some years old), but the hydraulics works fine for a few days, then gets sluggish for a few days, then barely works. My first screen cleaning (looked like it was full of dirt, iron filings and snot) lasted about a month. The second cleaning (more dirt, iron filings and snot) lasted another month. Third cleaning, same thing. I am new at this tractor business, and trying to embrace the learning curve. Thank you two for your good advice. I will try to look somewhere else (like maybe flushing the bottom of the rear axle drive thingies) as my neighbor recently pointed out to me. My reason for the after market hydraulic filter is to scrub the hydraulic system for about a year, then remove the filter and go back to regular periodic maintenance.

One thing I noticed when cleaning the screen is that when the oil was drained it was very thin (similar to SAE-20 motor oil). The WSM specified SAE-80 Hydro-Gear Oil, which I cannot find. I can find SAE-80 Gear Oil, but not the kind for hydraulic systems. The local Kubota dealer is only interested in selling me more oil, and not really interested in helping diagnose the problem. In checking with the hydraulic and gear oil manufacturers they say that their Hydro-Gear Oil is similar to multi-viscosity SAE 10W30. So now i'm wondering if the Kubota UDT is too thin? What do you guys think? Dusty 
//


----------



## DustyTrails (Apr 22, 2017)

I'm not sure any adjustments are necessary. But I would still like to know where to make then if or when they become necessary. What I do know for sure is that the previous owner was not big on periodic maintenance, and that bothers me a some. I don't know how many hours on it because the hour meter has been replaced. I do like that the tractor is not all banged up and runs good. It looks like it was kept inside.

Thanks again for your input, Dusty
//


----------



## RC Wells (Dec 26, 2008)

Universal Tractor Fluid is just fine. Do not use 80 wt gear oil, that will create no end of problems. I like the Cenex Qwiklift HTB as it is high quality, approved by Kubota, and inexpensive. It also does not hurt that it is green and easy to see. But, the cheapest WalMart UTF would work well too.

Sounds like a complete transmission flush is in order, you are on the right track.

The problem with an add on hydraulic filter in your system is that you are feeding 2,500 psi oil pressure from the pump, even in the return line where it supposedly just dumps back in the transmission the pressures can exceed the rating of the add on type filters. Surge it on a cold day and the pressure will jump even higher temporarily. The type filter you were considering has a burst rating of 400 psi. The loader valve bypasses the oil at full available pressure, and in theory once the demand load is not present the pump just circulates the oil at low pressure. But, I have seen just about every major tractor brand blow the return lines because of the unexpected things we do in the real world. It can be a real pain to pump your system out in the field or on the road, but usually the operator discovers the oil flow when they park in a clean machine shed and discover a major spill on the floor.


----------



## RC Wells (Dec 26, 2008)

There is no volume adjustment on your tractor. The bypass valve determines the total available pressure, and is only adjustable by manually stretching the spring or stacking spacers under the retainer - neither option is safe as hose ratings are the effective limit of pressure, and you do not want to blow a pressure hose and deal with the spray of oil. If the old bypass is failing it is best to just buy a rebuild kit.


----------



## DustyTrails (Apr 22, 2017)

OK then, so I will just keep cleaning the screen? Wish there was a better way. I guess I can keep replacing fluid with the Walmart brand UTF to save a little $$$.

Sounds like the next thing for me to do is get a gauge and see just what the pressure is. The WSM says should be about 2000 psi. Thank you for your good help, Dusty
//


----------

