CK20 HST geyser of HST oil from dipstick check

[malk315]

Well today was first day of mowing after the events described in this thread:

http://www.tractorbynet.com/forums/kioti-owning-operating/89118-ck20-hst-oil-overflowed-dipstick.html

Right after mowing I parked the machine by the shed and left it idling for a bit since I read that it's good to do after under load for a while.

I used my leaf blower to clean the grass, pine needles etc that collect on the deck and after that decided to check if the dipstick tube had any oil on it indicating any overflow... Well as soon as I took my hand off the dipstick when checking to make sure it was in all the way and hadn't work it's way out, it literally exploded HST oil in a geyser high enough that it was flowing on to the dashboard in a large stream the size of the dipstick tube. My immediate reaction was stopping the tractor, and then frantically getting the dipstick back in there to stop the flow.

After mopping up probably a good few quarts of oil off the entire operating area and mower deck etc., I decided to unscrew the red filler cap and it was like opening a two liter bottle of soda that has been shaken a bit... a lot of air pressure hissed out, but luckily no oil.

Had to have my friend w/ his B7510 come tow me home!!

I started the tractor and put it in neutral -- some questions:

Hydraulics for MMM deck lift and loader are independent of HST tranny oil right?

W/ all that oil that came out, have I risked damaging anything by just using the HST steering to steer the tractor during tow? Also, will having the engine running w/ hi/low in neutral cause any damage?? i.e. input shaft to tranny spinning with obviously rather low HST oil content won't be an issue. It only ran for about 5 mins just to pick up bucket and steer some.

After shutting down and pulling dipstick, the opposite happened -- vacuum of air went into dipstick hole, and now no fluid registers on the stick, so obviously way too much oil came out.

More questions:

How much pressure should there be on that dipstick? If it's anything like mine, it's going to AT A MINIMUM need a SCREW ON dipstick as any rubber stopper is going to shoot out of there under the kind of pressure mine has developed.

Is this possibly due to an overfilled HST fluid or wrong type of fluid by dealer?

The tractor was purchased brand new in July, 2006 (3 months old, 24 hours on hour meter). It's only been used for mowing and light loader work.

I'm not happy and plan to visit my dealer tomorrow with my tale of dissappointment. If this problem can't be solved properly (i.e. a new stopper and refilling causes this to happen more), I will simply sell the tractor.

That dipstick is like a ticking timebomb and could spew a lot of oil when the pressure is enough -- it's probably a lot hotter when actively mowing as opposed to having cooled for a few mins in this case and I'm going to be leary of getting burned if it does it while working.

Anyway -- any insight from you guys would be appreciated. It'll be interesting to see how the dealer handles this...

Eric M.
CK20 HST, 24 hours
MMM, KL120 loader
Disappointed with Kioti at this point...

 

[Egon]

24 Hours.

It's right back to the dealer time. Don't even try any fixes.

 

[Highbeam]

The red fill plug for the tranny with the little snorkel is a vent. It needs to vent. When you say that removing it caused any sort of air movement I would be concerned that it's pluggage may be your issue.

Kind of like a blocked fuel tank vent can kill an engine or collapse a fuel tank.

You should be able to blow through the little red snorkel. There should be zero pressure or suction working on that dipstick so don't worry about trying to get it tighter fitting.

You have a single sump and pump for steering, HST, hydraulics, and the 3ph. I lost as little as a gallon from the sump which rendered the tractor dead.

 

[ccdck20hst]

That was a pretty bad expereince and you must have been displeased to get all that fluid over your sub 25 hour tractor. I have almost 100 hours on my CK20HST TLB and still make an effort to keep it clean. I have read here that the hydaulic fluid expands, I think as it gets hot - I might be wrong on this. Well a good place to start is always the owner's manual. Page 5-2 CK20 owner's manual DAILY CHECK "CAUTION To aviod personal injury: Be sure to check and service the tractor on a level surface with the engine shut off and the parking brake "ENGAGED"' 5-2 also "Check item . . . Check the tansmission oil level" Chapter 9 page 9-37 of the CK20 Workshop Manual "Hydraulic System a.Changing the Transmission Fluid Caustion To aviod personal injury : Allow engine to cool down sufficiently, oil can be hot and can burn . . . 4. After running the engine for a few minutes stop it and check the oil level again: add oil to prescribed level.. . . Do not operate the tractor immediately after changing the transmission fluid. Run the engine at medium speed for a few minutes to prevent damage to the transmissoin." (Again from page 9-37) So, from all this literature it looks like one must always stop the tractor before checking the transmission fluid and preferably let it cool! That said (and I KNOW NEXT TO NOTHING ABOUT THE HYDRAULICS OF OUR TRACTORS OR HOW TO SERVICE THEM THUS I READ A LOT AND TRY TO LEARN. When I had this delivered it took me fifteen minutes to figure out how to start it even after I was shown how) you still could have a problem that someone who really knows these tractors can spot from what you described. So, having your dealer check it all out is the best thing to do undoubtedly. Good luck.

 

[malk315]

Here's something else I just realized --

Before the geyser event (see thread referenced in first post in this thread) I had started the tractor at about 10:00 a.m. the day before since it was chilly out (frost on the ground) to see how it would do on a cold start. I pulled the machine out of the garage 15 feet and let it warm up until temp gauge showed normal (about 20 mins of running at bout 1200 or so RPMs). Then I backed it 15 feet into garage (all in low range, very low speed) and shut it down. I noticed that first very small amount of oil that seeped out of the HST dipstick check and wiped it up.

At about 2:00 p.m. (4 hours later!!) I wanted to investigate the leak some more and isolated it to the dipstick filler. The tractor tranny case was stone cold at this point (ambient temp was 40 - 50 F). I pulled the stick and several ounces of oil overflowed out the dipstick check -- enough to make about a 1-1.5 foot diameter puddle down by the mower deck. So if after 4 hours of cooling and tranny stone cold to the touch, it spews several ounces of oil, it's obvious to me something is wrong beyond a heat expansion thing.

I think Highbeam's info about the pressurizing of everything due to the red filler cap up by the seat not venting properly has much merit here -- I agree that oil can expand and such, but that expansion should not be so much that it spews quarts of oil out... in a stream as high as the dashboard!!!

Yes -- I'm kind of clean freek w/ new equipment and I'm very disappointed that my 23 hour tractor has oil EVERYWHERE and will collect dust a lot more unless I wipe up every nook and cranny -- I'm pissed I won't be able to wipe up areas behind the instrument panel and such w/o taking all of that apart... Will my dealer wipe everything to get it as clean as I would like it--- probably not...

Thanks for the quick replies. I will report back on what the dealer does when I visit them tomorrow (I plan to visit in person rather than phone call to be completely clear on what has happened etc. (other tractors will be on hand for reference and I will certainly examine the red filler caps on each for how they might be vented etc.)). I will also probably pull the dipsticks on machines on the lot to see if any appear to want to spew oil etc.

I'll provide a full report.

-Eric

 

[IslandTractor]

Sorry to hear of your mess. I suspect Highbeam's answer is the key to your problem though.

I now have 140 hours on my CK20HST and have never had any leak from the dipstick hole at all. I actually was just checking mine today and added the first quart of hydraulic oil since I got the machine 110hrs ago. When I took off the red cap that Highbeam refers to but I did not notice that it was a vented cap. If it is not there must be some other vent in the system that could be clogged (but Highbeam is presumably correct that it is the cap)

While on the subject of hydraulic oil and the CK20..... what sort of usage are others noticing? I lose a little occasionally when I disconnect hydraulics (BH, grapple) but in total I was down only a quart after 110hrs which seems pretty reasonable. (My dealer did the "50hr" change at 30 hrs when I bought the tractor slightly used)

 

[Highbeam]

It's not so much that the oil expands when ity gets hot but that the air inside the case expands quite a bit with heat.

From the physics days we have the law of pivnert, no need for details (like absolute values) but if you double the temperature of a set volume of air then either the volume needs to expand by 2x or the pressure needs to rise by 2x. If the vent is plugged then you are getting no expansion of the air so the pressure doubles and blows hot oil onto your dash, or into your beer.

Now if ambient air temps are 30 and the oil can heat up to 200 then the air needs to heat to 200 and that makes mucho pressure in a sealed tranny. Maybe there is another vent in the system somewhere, but if not, the case pressures can be high.

New tractor, let the dealer clean out the vent hole. Older tractor, remove the fill plug and confirm ventilation (maybe even leave it out) then refill with oil and try again.

I'm on the edge of my seat with anticipation for the solution.

 

[BTI]

The oil is usually between the upper and lower marks when we get the units in.
Sometimes we have to top them off after a loader install.
Be sure that your oil level is at least a little under the upper mark and that the loader is just slightly raised or flat on the ground and that the bucket curl is in mid-range. Normally it doesn't make alot of difference, but I could see that if you always have the bucket uncurled,the loader raised and the level is at the very top mark, the expansion that has been discussed could make enough difference to cause trouble.
Does everything hydraulic work fine when the unit is running?
The CK20HST has a very fine line between full and over full.
With HST fluid being so clear it is hard to tell sometimes where the oil actually is on the dipstick.
We have filled, then turned around and had to drain some out more than one time. LOL
We fill them very little at a time.

BTI

 

[wallace]

Hmmm. I am wondering if the system was over filled from the get go.

 

[malk315]

If she was overfilled from the get go, I would have expected overflow earlier... Not 23 hours of operating and then all of a sudden it starts doing this.

After the first episode of the small amount on the garage floor, the dipstick was reading right on the full mark -- not over full. This was after 4 hours of cooling off on a 40-50 degree day. Tranny stone cold to the touch.

Called dealer this morning and he agrees it's a venting issue. He wasn't sure how a CK-20 would vent (told him about the venting of the cap on highbeam's tractor) but he plans to find out and go through the whole hydraulic system on it.

Coming to get the machine wednesday eve -- I could tell he flet bad he couldn't come get it earlier as they are short of staff right now. It's fine as I won't need the tractor and can handle a week or two of down time if necessary.

I'm glad everyone agrees there shouldn't be any pressure on the dipstick for checking... if some amount of pressure there was normal, many tractors would spew oil like this as a screw on dipstick would be needed to prevent it. Hopefully it really is either simply overfill or something clogged that would normally vent it, and not some serious tranny issue. Either way I hope the root cause is isolated and fixed... I don't want something to be working improperly for many hours of operation, and then have my whole tranny die after the tractor is out of warranty -- that would be my luck -- murphy's law would have it machine would crap out after warranty is up. I have this syndrome where I always get the broken one! Especially somehing I buy that has to be put together -- I always get the one that's missing some piece of hardware required for assembly -- gas grill, kid's toy tractor, treadmill, put-togther furniture, etc. etc.

I'll keep everyone posted on what the results are.

Anyone out there familiar w/ how the hydraulics would normally vent on a CK20??