NX 5010HST Cab reverse intermittent and jerky

[dusty3030]

I know the pump is split- but what is the flow rating for each leg? Usually the power steering/ hst is a lower portion of the total gallons per minute.

 

[dusty3030]

Both hard lines coming out of the pump are the same size. One goes to loader valve and the other to the modulate valve.
The power beyond out of the loader valve is a 1/2 “ line to your rear remote.
The line from the modulate valve to the power steering valve is only a 3/8” line. The line to the pro clutch is even smaller. So big line into the valve and a smaller line out that has to feed the power steering, goes through the cooler then feeds the HST. What is perplexing is that the steel line jumps back up in size between the cooler and hst filter and is a larger diameter line from the hst filter into the hst unit. So is the hst needing more fluid than the 3/8 feeder can provide causing aeration? How much flow is the pump trying to pump through the 3/8 power steering line?

 

[dusty3030]

Hard line into modulate valve larger than the 3/8 coming out. Shows both hardliners out of pump the same size. Hard line that drops down from cooler to below the alternator hooks up to a larger diameter hard line that goes into the hst filter.

 

[TN8Man]

Here is a good article in aeration and cavitation.

Aeration vs. cavitation in hydraulic system design

 

[Robin Veerman]

That is indeed a good article above. I use Amsoil in my HST and I'm extremely happy with it. Very smooth operation of the HST whether it be in the summer's heat or winter's cold. Read the link in the following article and see if it meets the extreme requirements that HST transmissions require. Dutchy Synthetic Tractor Hydraulic/Transmission Oil SAE 5W-3 ATH - AMSOIL

 

[TN8Man]

It shows viscosity of 10.1 cSt @ 100°C. That's better than most Ive seen and one of my key concerns.

 

[YLee Kioti]

That is indeed a good article above. I use Amsoil in my HST and I'm extremely happy with it. Very smooth operation of the HST whether it be in the summer's heat or winter's cold. Read the link in the following article and see if it meets the extreme requirements that HST transmissions require. Dutchy Synthetic Tractor Hydraulic/Transmission Oil SAE 5W-3 ATH - AMSOIL

I used the product in the CK4010HST, as it was a 5 gallon capacity. But at 12 gallons that is just a bit way to steep.
So for now using Kubota's hyd oil. They are 14 miles away and should be good for any tractor. So far 60+ hours and seems to operate just as well as the NAPA Coastal full synthetic.
Course been to dry to cut much and property is now in maintenance mode and so the land clearing phase is done.....

Sure would go a long way if Kioti, or any mfg. for that matter would be willing to be proactive when a customer has a issue that is out of the ordinary.

 

[TN8Man]

Update on my NX50HSTcab failure mode (intermittent loss of reverse, jerky hydraulics, excess heat in HST >200F):

Glad to report my tractor seems to be fixed, finally. The local shop cracked open the HST and replaced solenoids. Apparently these solenoids were known issues and Kioti recently changed suppliers.

I have used the tractor under the same conditions where it failed (except ambient temp is now in the upper 60's instead of upper 80's) and it has not failed and the temp near the hydraulic fill port is now ~150F instead of well over 200F. I even used the big bush hog with no issues.

Hopefully the problem is gone for good.

 

[YLee Kioti]

Thanks for this update.....it seems to be a trend about mfg. responding slowly to known issues and never acknowledge them.
Back in the day my 7.3l PowerStroke had a camshaft sensor issue known to fail by shutting down engine.
The diesel boards were lit up for months on this topic.
Many of us flooded the NHSTA and recorded our issues......mine died as I crossed a set of tracks.......uh....yea...!!!......

Since I'm sub'd to this thread is I have any issues I'll share this with my dealer.....who has a track record of excellent service and responses....

Give us a 25/50 hour or so update......if you remember that is....lol....

 

[TN8Man]

Thanks for this update.....it seems to be a trend about mfg. responding slowly to known issues and never acknowledge them.
Back in the day my 7.3l PowerStroke had a camshaft sensor issue known to fail by shutting down engine.
The diesel boards were lit up for months on this topic.
Many of us flooded the NHSTA and recorded our issues......mine died as I crossed a set of tracks.......uh....yea...!!!......

Since I'm sub'd to this thread is I have any issues I'll share this with my dealer.....who has a track record of excellent service and responses....

Give us a 25/50 hour or so update......if you remember that is....lol....

Yep, even the shop manager did not offer up the "known issue" part until I pressed him on it. I don't think their profit margin on warranty work is as good as non warranty work.