Jerky Hydraulics-

[brianidaho]

Hi All,

I have just started having problems with the hydraulics with my Shibaura D23F. When I raise the FEL or 3-pt the motion is slow and jerky, it sort of starts and stops irregularily. Lowering works fine, nice and smooth. In addition, the power (pressure) seems to be down, I have trouble now lifting the front end with the FEL. The last couple of days are the first time I have run the rig in cold weather.

OK, here's some history, I bought the tractor this spring, I think it's around a '90 model. After a month or so of use, my trans light came on as the fluid warmed up, when it got really warm, or if the RPMs were low it would go off. Based on some feedback on this forum, I was led to believe I probably had water in the fluid. I drained the fluid and changed it and the filter, it did look nasty, kind of milky. I put in new fluid, problem was much reduced. I chanced fluid and filter a second time, to further purge any moisture, things seemed fine. I ran the tractor for several months with no further problem.

I just pulled the pressure relief valve apart, I was thinking it might not be sealing and not letting the system achieve pressure properly. I did clean some grunge out, but no help. The problem seems to be varying pressure, but I don't have a gauge on the pressure line to check, yet.

Given that the pressure seems down and flow seems "intermittant" (and I can hear fluid hydraulic fluid moving in the lines that doesn't sound smooth, I dont know how to describe). I was wondering if I am cavatating due to some restriction on the suction line of the pump? Is it possible that there is a suction strainer that may be partially plugged? Letting the tractor warm doesn't seem to help and the problem seems to be there at all engine speeds.

More questions-where is the hydraulic pump located on this tractor, or in general where are they usually located? I have some experience with industrial hydraulics, but not much with tractors. Also, if there is a strainer in the line, or anything else that may be getting plugged, where would I find it? If there isn't a restriction of some sort in the suction line to the pump, I am assuming the pump is going bad. I understand that tractors typically use gear pumps, I assume these aren't too expensive, does anyone know what one should run? One more question, I am assuming that the spin-on hydraulic filter is on the return line to the reservoir/transmission and not on the suction line to the pump. Is that correct?

Thanks for any help you can offer.

Brian

 

[lens12]

Sounds like a partially plugged pickup screen. The pump is on the right side at the front of the engine. It has 2 metal lines fastened to it. The filter is on the sustion line. 2000 psi would blow up a filter. Follow the short line from the hydraulic filter back to the transmission , The 3 bolt cover that it is fastened to can be removed & the screen pulled out , & cleaned.

 

[brianidaho]

I just pulled the inlet screen, you are right, it is nasty plugged. I have cleaned it, the plastic bond between the stainless screen is a bit bad, I'd like to replace the screeen. Anyone know where I can buy a replacement?

Bri

 

[brianidaho]

It took some time to clean all the gunk off the screen. At first I thougth I had a real problem, there appeared to be a 1/4" key stuck on the screen, finally figured out that there were several magnets attached to the inlet screen. They did a great job of holding fine metal filings. There was a lot of grunge, maybe brake material(??) or scale on the screen, pretty badly plugging it.

The stainless screen and metal can inside it appeared to be bonded to the inlet fitting. This had partially failed, I pulled the screen and can, cleaned everything up, and bonded it with JB Quick-Weld. I just got everything back together and ran it, everything is working fine now, perhaps better than when I got it. I wish I had known about this screen earlier, pulling and cleaning it will be a regular part of my annual maintenance from now on.

Thanks for the input.
Bri

 

[Egon]

Good to hear some others were able to help.

Egon

 

[Dewey_Williams]

I have Shibaura D28F and I have the same problem but I can't find the filter your talking about I followed the small line to the trans but it has one bolt that goes through the end of the line to fasten it. Did you have to drain the fluid in the trans to clean the screen. My filter is at the trans the filter is on the large line. The large line comes from the pump back too the filter then it goes into the side of the rearend.

 

[brianidaho]

Sorry for the delayed response, I haven't checked in for a while. If your rig is plumbed like mine, the large (approximately 1") line is running from the transmission to the spin-on filter and from there to the hydraulic pump. It is the suction line, fluid is picked up from the transmission, and pulled through the filter. Follow this line back from the spin on filter to the transmission. At the tranny there is a flange held in place by 3 machine screws, where the supply line ties in. This flange (at least on mine) is actually a housing and has the strainer attached to the far side.

You will have to drain all the fluid to pull the strainer. The 1" line is just pressed on this flange via a sort-of snap fit over an o-ring. You probably will have to pull the 3 screws, then gently pry off the suction line at the filter housing and the flange to get the flange/stainer off. The screen or strainer is actually bonded to this flange, don't try to pull it off.

Once you get the strainer out, you will find a spring over the strainer, this spring holds some magnets in place, you'll want to pull it off and pull the magnets off to clean out the screen. The screen is stainless steel mesh, I cleaned mine up with some diesel and toothbrush. Getting the 3 fasteners to line back up along with the supply line, all the while dealing with the strainer housing with RTV on it is a bit messy and annoying, but not to bad.

Let us know how it goes, good luck.

Bri

 

[kayssupply]

If you get a chance post a picture of your Hydoangle blade. That sounds interesting.

 

[Dewey_Williams]

Hey I found the filter and it was just as you said stopped up with sluge. You was just a little late getting back, but man what a difference it made. Thanks for the info though. I hope I don't have to do that often. My tractor still had a japan filter.