Hope that you never see your HST like this

[dannydan3]

HST replaced for $1700, and just for fun, I had them return the old parts (minus the case which was also unrepairable)

The second pic is the scoring damage that the mechanic said stopped the fluid feom flowing through. He said it was crud in the fluid.
Where it came from is a mystery, I was always on top of maintenance, even changed the fluid after 3 original hours to get the initial break in metal shavings out. Cheap fluid and hard use most likely the culprits I guess.
Needless to say, it's only HDT from here out.

 

[milkman]

I'm inclined to believe that trying to make it run with no fluid is the cause of the scouring that created the eventual complete failure. Tractors are made to work and a lot of us here have put a lot of hard hours without failure, your damage just looks to me like metal to metal damage.

 

[HomeBrew2]

Agree w/ Milkman. You can't run a machine without lubrication, period. Just my opinion, cheaper oil and hard use combined with regular maintenance may only account for shorted service life and/or decreased functionality, not complete self-destruction. I'm still in amazement that that repair was so cheap.

 

[RonR]

A lifetime ago, I attended a week long hydraulics school in Detroit. We worked with the HST type units, but larger for ag applications.

One of the lab sessions, we had a variable speed pump/motor that had the ability to starve oil going into the unit. As it was up to speed running normally, you restricted the oil flow going in with a valve. It grew louder and louder, eventually hammering like crazy.

When we disassembled it, you could see the pitting damage. The instructors said it was caused by high pressure AIR detonating on the metal.

It doesn't take much of that to mess up a transmission. Then all the debris is in the system floating around causing more damage.

ron

 

[dannydan3]

I'm inclined to believe that trying to make it run with no fluid is the cause of the scouring that created the eventual complete failure. Tractors are made to work and a lot of us here have put a lot of hard hours without failure, your damage just looks to me like metal to metal damage.

Probably, since I had no idea that the machine had lost all of it's fluid until I looked back and saw the puddle in the lawn.
Grass still won't grow there.
I was also suprised that it was so cheap, I was ready to sell it to the dealer "as is" if it was as I originally expected - I thought around $4000 (I was extremely nervous as one would expect)

 

[Soundguy]

That would be cavitation damage... pumps that starve for oil are prone to it.. the vapor pressure of the oil is lowered allowing gas pockets to form which then implode

I have to agree with the others.. this looks like a lack of lube.. not a hard work / wrong lube issue.

I'd wager that jiffy store 30w engine oil would have produced better results than running low on the correct lube.. etc. IE any oil is better than no oil..

Soundguy

A lifetime ago, I attended a week long hydraulics school in Detroit. We worked with the HST type units, but larger for ag applications.

One of the lab sessions, we had a variable speed pump/motor that had the ability to starve oil going into the unit. As it was up to speed running normally, you restricted the oil flow going in with a valve. It grew louder and louder, eventually hammering like crazy.

When we disassembled it, you could see the pitting damage. The instructors said it was caused by high pressure AIR detonating on the metal.

It doesn't take much of that to mess up a transmission. Then all the debris is in the system floating around causing more damage.

ron

 

[Soundguy]

Metal to metal, under load, and or cavitation doesn't take long to eat deep into a checkbook.

As for the oil patch... you can mitigate it somewhat with a surfactant.. nothing too alkali though... Just pour or sprinkle in the area.. wet.. rake in with a garden rake.. soak with water.. and then let nature start doing it's work..

Conversly.. you can excavate it and put it in an old 55g drum and burn it off and then replace...

Soundguy

Probably, since I had no idea that the machine had lost all of it's fluid until I looked back and saw the puddle in the lawn.
Grass still won't grow there.
I was also suprised that it was so cheap, I was ready to sell it to the dealer "as is" if it was as I originally expected - I thought around $4000 (I was extremely nervous as one would expect)

 

[Acolar]

My HST failed after 203 hours on mg GR2100. I changed the trans fluid at 50 and 175 hours. Used Super UDT and Kubota filter. Noticed sand looking residue on the suction screen along with metal shavings @ 50 hours. Kubota did not seem concerned. Then @175 hours another fluid change more residue and large pieces of metal. The the cooling fan fastners vibrated loose and the fan came off. Within another few days the tranmission failed. Went to dealer Sept 18, still there its Oct 19. Just got all the parts in yesterday. No complete replacement of trans, they are rebuiulding it. Luckly it made it under warranty by a couple of weeks. Now the warranty reapir is only covered for 90 days. Hope its not a design defect and I have another reoccurence. No assistance from Kubota Credit as they still want my monthly payment. I will never buy or recommend Orange ever again.

Tony

 

[Double Orange]

Acolar, I know your upset! As would any TBN'er!
Nobody makes any piece of equipment thats a 100% perfect ie "The Titanic."
As far as Kubota Credit wanting payment while in the shop, do you think J.Deere credit/New Holland/ G.E.Credit would have been any different?
Your newly rebuilt trans will be fine,

All I'm saying is life's too short to sweat the small stuff!
You want to worry about something......close your eyes and when open them imagine being an POW in Iraq!

Feel Better!


Live Well!!
Die Strong!!
Frank

 

[alchemysa]

I dread to think what the inside of my HST looks like. The screens were jammed behind the loader and backhoe subframes and I suspect they were never removed and cleaned since new in about the mid 80's. Not long after I bought it (a couple of years ago) it came to a total stop. Advice here on TBN correctly directed me to the probable cause. I unbolted the BH subframe, removed and cleaned the screen and replaced the oil. I was back in business very cheaply. I was very lucky. (For once!)