Kioti CK30HST loses hydraulic power

[brkdrvr]

Just saw this and thought I'd throw in my 2 cents. I have had similar issues with my CK20HST (857 hrs), I have the misfortune to be on my 3rd hydraulic pump. My unit has a pump driven off the end of the engine cam shaft, apparently sometimes the cam shaft end breaks and or the pump fails. I have no idea the variations between our machines but, I will note that the HST drive works when the hydraulic pump has failed but the FEL, backhoe and three point hitch have first low and then zero power (you can drive the tractor onto a trailer with a failed hydraulic pump).
The Kioti dealer I purchased from had the 1st pump replace under parts only warranty ( under 350 hrs). I replaced the 2nd pump myself when it failed ( @ 450 hrs) and fully flushed hydraulic the system 3 times with all filters being changed & magnets being cleaned. My repair has lasted longer than the Kioti dealers by double. Out of an abundance of caution I now run a recirculation hose between the hydraulic ports for back hoe when its not in use and plan to fabricate a lock out so the hydraulic directional lever A - N - B ( directly along side the 3 point hitch lift lever) A/B cannot be pulled back to A causing hydraulic to dead-head (sorry don't know correct term, hydraulic pressure obiously builds up and causes machine strain/stess). I am not sure if you are inclined to repair or figure out for yourself I highly recommend contacting Bob Piro at Michigan Iron and Equipment even if you are not near him, I am located 1000 miles away but had zero luck getting help from Kioti and my local dealer operates with the Ferrari/yacht dealer philosophy... if you have to ask what it costs you can't afford it, the mindset is to down and the parts and service guys talk down to everyone unless you are a certified diesel mechanic. Bob Piro is a very professional, knowledgeable, experienced Kioti Dealer who will give you good diagnostic advice. I now get my parts and supplies from Michigan Iron and Bob is probably the only reason I still own my Kioti. Sorry for the lengthy reply, your initial description of the system weakening just sounded almost exactly like the symptoms leading up to my pumps catastrophic demise. Good luck, Mike

 

[Tony H]

Folks here are saying the problem started AFTER the filter/flued change. That's not correct.. You did fluid and filter AFTER you had the hydro issue.. Correct?
FEL and 3Pt hitch are a problem yet driveability is still OK.
Was hydro fluid low when stuck in ditch? Maybe low fluid starved the hydro pump? Maybe hydro hose that breaks off to front and rear hydraulics is pinched. You said all looked good but maybe check again

 

[jmk121]

Just saw this and thought I'd throw in my 2 cents. I have had similar issues with my CK20HST (857 hrs), I have the misfortune to be on my 3rd hydraulic pump. My unit has a pump driven off the end of the engine cam shaft, apparently sometimes the cam shaft end breaks and or the pump fails. I have no idea the variations between our machines but, I will note that the HST drive works when the hydraulic pump has failed but the FEL, backhoe and three point hitch have first low and then zero power (you can drive the tractor onto a trailer with a failed hydraulic pump).
The Kioti dealer I purchased from had the 1st pump replace under parts only warranty ( under 350 hrs). I replaced the 2nd pump myself when it failed ( @ 450 hrs) and fully flushed hydraulic the system 3 times with all filters being changed & magnets being cleaned. My repair has lasted longer than the Kioti dealers by double. Out of an abundance of caution I now run a recirculation hose between the hydraulic ports for back hoe when its not in use and plan to fabricate a lock out so the hydraulic directional lever A - N - B ( directly along side the 3 point hitch lift lever) A/B cannot be pulled back to A causing hydraulic to dead-head (sorry don't know correct term, hydraulic pressure obiously builds up and causes machine strain/stess). I am not sure if you are inclined to repair or figure out for yourself I highly recommend contacting Bob Piro at Michigan Iron and Equipment even if you are not near him, I am located 1000 miles away but had zero luck getting help from Kioti and my local dealer operates with the Ferrari/yacht dealer philosophy... if you have to ask what it costs you can't afford it, the mindset is to down and the parts and service guys talk down to everyone unless you are a certified diesel mechanic. Bob Piro is a very professional, knowledgeable, experienced Kioti Dealer who will give you good diagnostic advice. I now get my parts and supplies from Michigan Iron and Bob is probably the only reason I still own my Kioti. Sorry for the lengthy reply, your initial description of the system weakening just sounded almost exactly like the symptoms leading up to my pumps catastrophic demise. Good luck, Mike

 

[jmk121]

Thanks everyone for the help. I talked to Robertson equipment and the mechanic said he thought the pump was bad also. I removed the pump and disassembled it. First the long bolts that hold the sections together two were not tight (they loosened with finger pressure around the head of the ratchet. Second the seal to the engine was leaking to the point where my engine oil is above the full line. Last the seal between the low and high flow sections was missing about a half inch section of the black rubber and most of the red rubber was gone. It does not look like any signifigant wear to the metal parts. I havnt put the new pump on yet. I am worried about where the rubber has gone. how should i go about flushing the system?

 

[Midniteoyl]

Should be screens on the suction side (in the sump) that are removable and cleanable.

 

[Robin Veerman]

We wish you good luck with all your efforts for sure. I’m surprised that you were able to get a pump so quickly. Maybe after you have it all back together you could show us what bolts to check that you stated were finger loose.

 

[jmk121]

Folks here are saying the problem started AFTER the filter/flued change. That's not correct.. You did fluid and filter AFTER you had the hydro issue.. Correct?
FEL and 3Pt hitch are a problem yet driveability is still OK.
Was hydro fluid low when stuck in ditch? Maybe low fluid starved the hydro pump? Maybe hydro hose that breaks off to front and rear hydraulics is pinched. You said all looked good but maybe check again

You are correct . I think hydro fluid was in the middle of the dipstick marks. I was wondering what angle if any would uncover the pickup for the pump. The tractor got very hot when I was trying to get it out that might be what damaged the pump.

 

[brkdrvr]

Thanks everyone for the help. I talked to Robertson equipment and the mechanic said he thought the pump was bad also. I removed the pump and disassembled it. First the long bolts that hold the sections together two were not tight (they loosened with finger pressure around the head of the ratchet. Second the seal to the engine was leaking to the point where my engine oil is above the full line. Last the seal between the low and high flow sections was missing about a half inch section of the black rubber and most of the red rubber was gone. It does not look like any signifigant wear to the metal parts. I havnt put the new pump on yet. I am worried about where the rubber has gone. how should i go about flushing the system?

I am not sure what is advised for your machine, after my experience with failed Kioti hydraulic pumps I erred on the side of excessive and fully flush all the fluid and changed both filters. The last pump failure I actually changed the fluid & filters twice, the second time after @an hour of operation. The CK20 holds @6gals of Shell SPIRAX S4 TXM which I get directly from ppc lubricants. On the CK20 there is a large center drain plug with a big magnet and two smaller outboard plugs to drain the rest. Both the pump failures I dealt with (yes I am on the 4th hydraulic pump) were more catastrophic than yours. The gear shafts actually ate through the bearing sleeves and began to destroy the pump case. I’ll try to post some pics. The 1st pump done by the dealer I never saw (civilians are too dumb to understand mechanical things) I was told the cam broke and I was running on 2 cylinders, there was a lot of smoke, Kioti paid for a new cam, hydraulic pump, misc parts and I was billed the labor. Some notes on 1st failure: 1. It happened when I was running scraper blade with the FEL off the tractor so I detached the blade and drove on trailer and dropped at the Kioti dealer to be diagnosed. 2. When I called after 5 days I was told the tractor was split in half, the pump was shot and the cam was broken. 3. After 2 weeks I called again and was informed the tractor was done and the bill was $XXXX.XX, when I started to get hot I was then told I only owed @50% as Kioti paid for all the parts since I was less than a year out of warranty. 4. I reviewed the bill and asked who paid for the 5 gals of fluid and filter & was told fluid was fine & reused never answered about filters. I asked what would have caused and never got an answer.

2nd dealer installed pump failed while clearing snow with backblade and FEL in @ 125 hrs & I replaced, fully drained system, cleaned drain magnet, replaced all filters also noticed tiny leak in hydraulic oil cooler and put into service.

3rd pump failed while trenching with backhoe in less than 100 hrs, fully drained, replaced filters & cleaned magnet. Before putting back in service I had a pigtail made up to fit hydraulic ports with a pressure gauge to confirm correct operating pressure with Bob from Michigan Iron I also purchased a recirculation pig tail hose to connect the rear output ports together so it does not deadhead/labor when the selector lever is put in back position when rear ports not in use. I sourced the exact SPIRAX Hydraulic fluid specified by Kioti corporate and then put back in service for @ 1 hour hooked up FEL and backhoe and ran through all movements to fully circulate fluid then shut down and drained system, cleaned magnet changed filters and refilled.

Additional Information:
*All hydraulic pumps were OEM Kioti.
*I used a torque wrench where ever possible.
*Tractor leaks/uses little or no hydraulic fluid never able to add more than 1/2 pint even after failure.
*Hydraulic fluid never smelled or looked foamy or burnt. It does darken slightly after 100 hrs use. You can see the darkening on dipstick/rag only when emptied in bucket.
*I have asked about how to flush and even Bob from Michigan Iron & Equipment thought my 2nd fluid change might be a bit extreme. The theory seems to be that the magnet and filters should get it all. That said I was told when my Suburbans transmission failed @ 40,200 miles and GM covered it anyway that if the tech saw anything he didn’t like during the replacement they would also replace the radiator and all the cooler lines because contamination left from a unsuccessful flush could kill the new transmission, tech said radiator and lines clean…..200,000 miles later and I’m still driving.

I figure an extra change out is good insurance, my next flush this spring a sample goes to Blackstone for analysis. I send out a sample of every other oil change for all equipment/vehicle now too.
Hope some of this usefull.
Best of luck,
Mike

 

[jmk121]

The new pump is installed. It works great. With the tractor hot (or cold) it will raise the front end off the ground and roll the bucket down lifting the tractor at idle. It will lift my 72 inch grader box to full height with the three point hitch at idle. Engine oil and filter changed. I reset the relief valve to 2600 psi. I will change the tractor fluid and filters after an hour or so.

Kioti had the pump at my door in two days from the time I placed the order. Best service I ever got from them.

Robin asked where the bolts I found finger tight are located. I believe the new pump is a Joy Yang pump. The Failed pump was a Casappa. In the photo below on the left end of the joyang pump is a black socket head cap screw. there are four of them on the the old and new pump equally space on the back plate. The only difference in the fasteners between the pump brands is the Casappa uses bolts instead of socket head cap screws.
There is a thread on here about these screws being loose because the threads pull out of the aluminum pump parts so be careful tightening them on an old pump.

If anyone has to do this job the only pointers are. You have to disconnect all the pipes (suction and pressure) to remove the pump. You cant assemble lines to the pump prior to installation. The large diameter suction pipe does have to be placed behind the pump against the engine before you put the pump in place. The pump to engine bolts have to be installed prior to installing the suction and feed lines. Dont ask how I found this out.

Thanks everyone for all the information and help. I really appreciate folks taking the time to read about my problem and being willing to help!!

 

[Tony H]

Big expense of new pump but glad you got it back to working. Do you think you could have replaced the gasket/o rings on the old pump or was there issues with the metal parts?