HST Problem/Advice

KiotiJohn · May 8, 2006

If the tractor has good traction and you pull on a virtually immovable object, the relief will hit. I suspect that if you had not had the diff lock on, you would have seen some spinning, but the extra traction caused the relief to hit when the tractor couldn't pull out the pipes.

In that case, some digging in advance could make a difference.
John

VictorW · May 9, 2006

dfkrug,
I'm no expert on the releif valve or how to exactly get a measurement on the pressure when it releases. I'm going by the past posts I read when another member had this problem and it turned out to be the valve. KiotiJohn had added good information and may be able to advise you better. Somewhere, and that is the 10 million dollar question, you have to connect a pressure gauge, put the tractor against an immoveable object and put the pedal down. Maybe my valve is set high but I can stall the tractor in high and medium range if the tires bite in to something. Low range in dirt will spin the tires in 4wd and diff lock with 2600 rpms. I never tried low on pavement. I would imagine the valve has a relief pressure spec. so as to protect the hydro pump. I understand your disappointment. I would be too. Maybe we will get some input here from one of the dealers. Sorry I couldn't be of more help. Maybe another part of the trator I need to learn about.

dfkrug · May 9, 2006

( If the tractor has good traction and you pull on a virtually immovable object, the relief will hit. )

Clearly that is what happened. I have been up against
immovable objects many times with different tractors and
I have never put the tractors into relief or stall. My backhoe
tractor is a Deere 955HST with new AG tires with slightly
more weight than the CK30. I have spun its tires (diff locked)
uncountable times against immovable objects. Never went
to relief.

I am wondering how often this happens to other owners of
other HST tractors (going into relief instead of spinning tires).
Makes me wonder if the Kioti HST relief is set too low. Is
this a bug or a feature?

CBB · May 9, 2006

I am wondering how often this happens to other owners of
other HST tractors (going into relief instead of spinning tires).
Makes me wonder if the Kioti HST relief is set too low. Is
this a bug or a feature? )

I pushed some dirt down a hill yesterday with the FEL and when I went to back up the grade, it would not go--throttle up and just touching the pedal. That is why I think the relief valve is not working right. I used my FEL to bump the tractor back and it backed right up the grade once started.

I agree---feature or bug? I think in my case, a bug. It is better since I toyed with the hydraulics valve but still not all there. I will say the CK 20 has a better lift to the FEL than our JD 990, which is 40 HP.

dfkrug · May 9, 2006

I have verified this happens with the other CK30HST I
bought last year. Never with any of the four JD955s I have
had. I still wonder about Kubota and NH HSTs... Anyone?

Bob_Skurka · May 9, 2006

(
I have verified this happens with the other CK30HST I
bought last year. Never with any of the four JD955s I have
had. I still wonder about Kubota and NH HSTs... Anyone? )

I use both Kubota and NH. Depending on the soil conditions, etc, I can either bog down the unit or spin the tires. It depends. So that is not much of an answer! /forums/images/graemlins/blush.gif But I guess it shows that under some conditions the relief valve is set high enough to allow the tires to spin on either tractor? The NH is a TC24, so it is very similar in size, and only slightly lighter in weight than a CK20. The Kubota is a B2910, it is unlike anything in the Kioti line up as it is very light. I would suspect that a lighter tractor would spin its tires easier than a heavier one because it would lose traction a bit earlier. On the other hand, if the relief is set too low, you can't use the weight because instead of losing traction you lose power? Honestly, I don't really know that there is a fair way to check all this unless you have different brands on the same ground because soil type really makes a lot more difference than many people realize. I have 2 totally different soil types on my property (top of ridge is 100% tan clay, bottom land is black as dirt but sticky and mucky with probably 65% clay content) and the tractors act totally differently depending on where on the property I am working. I also have 6 acres several towns away and the soil there is sandy loam and the tractors will break traction there long before they bog down.

You will often find that I recommend different things for different soil types because of my experiences. I have a 50" tiller that my 24hp NH can easily churn through thick sod on the sandy loam, but the 30hp Kubota will bog the engine down in the sticky black clay of my bottom land.

Traction works the same way in that different soil conditions allow totally different characteristics in how the tractor's tires and transmission work. So if you are bogging down one brand while not doing it with another brand, AND you are doing it on the same soil, then I'd say you have some things to look at with regard to the relief valve.

unhappykioti · May 9, 2006

( Take your tractor to the shop NOW, mine was doing the same thing it was fine as long as you were on flat ground but if you needed the power to go up an incline it just would not go. My tractor has been in the shop now for a month the dealer has been working with Kioti tech support have changed some parts and made some adjustments but it is still not right so they are thinking it has to be internal and are splitting the tractor. No idea when I am going to get my tractor back. ) My tractor has had the pressure relief valve replaced along with some other unknown parts, everything that has been recommended has not fixed my tractor. Got a call about an hour ago they are replacing the whole HST unit. This tractor only has 30 hours on it that will probably take another two weeks. One would think that as long as my dealer and Kioti have been trying to fix this problem they would air freight the HST unit to the dealer so I can have my tractor back. Your problem sounds like the problem I had.

KiotiJohn · May 9, 2006

No doubt that something is wrong if you can't get up that slope. I have one steep bank going down to a creek that is the worst, and I have no problem in 4WD and low range going F/R up the incline.

The HST pumps do sometimes have problems from the git go. They seem to either work well, or just not.

The pressure relief valves can be checked, the dealer should know the procedure, but Kioti service will instruct him in the procedure. It must be done properly off the ground with pressure gauges attached. Braking while operating the HST will send the pressure to relief and the dealer will be able to determine if it's hitting too soon.

John

HODAK · May 10, 2006

Just a reply in general. I have been following this post and just last night I was leveling dirt, rocks, and 23 tons of #2 modified stone. I can honestly say that My CK30HST will either stall out or spin in LOW range 4wd. (It stalled once last night while the operator was trying to get a little extra in the bucket). Generally, if the PTO is not being used, I operate around 2000 - 2200 RPM. I know what the relief sounds like and this only occurs in med, (or high range). Just my two cents........

VictorW · May 10, 2006

Hodak, I glad I'm not the only CK30hst owner who can stall the engine. I was starting to think that something was wrong with mine but it sure does push or pull good. /forums/images/graemlins/grin.gif