Oil & Fuel CK20S hst - trans fluid pressure forcing past dip stick

[tlschaeffer]

Went to changeover equipment on my Kioti ck20S hst yesterday after it sat covered for a week or so. Noticed a wet spot on the gravel and chased out leakage which was the dip stick under the seat that goes to transmission reservoir above rear axle assembly. When I removed dipstick, trans fluid pushed up and out tube. Never have encountered pressure build when I checked dip stick before; whether machine hot or cold. I tried to relieve all hydraulic pressure on tractor including FEL, hydrostatic drive, 3 point. Still positive pressure pushing fluid up to top and out of dipstick tube. After awhile it seemed to retreat to normal operating level.

Today (hot, ambient air temps and in sun) the fluid pressure was again raised and pushed out when dipstick removed. I checked with a Kioti certified mechanic who is not practicing but runs a local auto repair service. He thought there should be one or two passive, one-way pressure relief valves mounted on rear axle and/or above transmission fluid reservoir. He implied they would be vertically mounted and that they could be removed and compressed air blown "out" (from inside) to clear dirt, mud, etc. I pulled the seat and metal plate cover underneath and I can find no obvious pressure relief valve. Guessing he may be thinking about another model Kioti. I called two dealers and so far have got the "we'll get back to you" runaround.

The last time I used the tractor, I did some maintenance including using some compressed air to blow out debris and dirt from the tractor including the rear end. I hadn't noticed any dripping of fluid before then. Not sure how I could have forced dirt into any orifice or caused this pressure build. Even if tractor is worked, fluids at operating temps, etc., shouldn't you be able to check hydraulic fluid without it being pushed out due to temperature related expansion?

Any insights or suggestions would be welcome. Thanks in advance.

 

[K5lwq]

Just a thought, is it possible that the tractor was overfilled with fluid? Or was there water in the fluid?

I can not see that happening at all. It was hot as all get out the last few days here and my level On the Kioti is just below the top line. That is where it was when I changed the fluid last year.

 

[tlschaeffer]

Just a thought, is it possible that the tractor was overfilled with fluid? Or was there water in the fluid?

I can not see that happening at all. It was hot as all get out the last few days here and my level On the Kioti is just below the top line. That is where it was when I changed the fluid last year.

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Based on another post, the same issue has occurred to others with the same model tractor. It's likely a plugged vent for the transmission/fluid reservoir causing heated fluid to push up the tube and past the dipstick. It apparently is isolated to hst models I believe. A couple of posters even display pictures, but unfortunately, they must have ck20s tractors older than mine (2011). I'm trying to find the exact name of the part and its location on my model year but coming up empty so far.

 

[tlschaeffer]

No, the level was fine and has been steady (no loss) since the last filter change about a year ago. I guess it's possible that water may have gotten in the trans fluid but I have no idea how, and I don't see any milky appearance of that kind of contamination.

 

[K5lwq]

I can understand a vent being clogged and forcing the dip stick out as pressure builds. I just have a hard time understanding how the fluid can expand that much.

But here is your part number. 76591-1135-1 It is called a Tube, Breather. If you look at Michigan Iron part lookup you can see where it is on your tractor.

Parts Finder Michigan Iron & Equipment Morrice, MI (855) 265-459