HST Trans

[ferguson]

Hi All Swapped out the HST on my l3130 with a used one / the original worked butt had a great loss of power / have it on the eng. stand/ started disassemble
both plates are destroyed picture of the rotary motor plate & swash plate - plate one completely gone/ things are a little chewed up/ but the tractor operated like this / also found a poppet lodged open with a piece the plates # 160 / all the other pieces were in the pluming & oil cooler / can't buy just the plats / it operated like this/ going to putt back together without the plates & save as a spare (THOUGHTS)

Can any one tell me what these plate do they are not machined pieces / there stamped metal with no close tolerances ???

 

[rbargeron]

When an HST fails in the slipper surfaces its junk. Kubota doesn't even ask dealers to return the old "cores" from swap-outs. There's no way to be sure of reliable function again.

When I had mine apart, the "money parts" were all still fine. I had even bought a complete extra unit in case the machine was apart and the HST wasn't repairable. Mine only needed the cradle bearing set, so I just replaced that. The spare HST I bought is now surplus. (fits Lxx10 machines and L48) Somebody may need it as time goes on....

Glad your tractor is functioning again - good doing! Dick B

 

[Mark_BX25D]

Punctuation exists for a reason.

 

[Pawnee]

My thoughts:

I read your original thread with great interest, watched as you finally figured out that the HST was the problem, and then saw the pics of your tractor split in half.
I don't think I would have the confidence to tackle that big of a job unless you were my neighbour.

Well done!

 

[ferguson]

Punctuation exists for a reason.

Not wrighting a novel / just facts & i KISS it

 

[Mark_BX25D]

noproblemyoudowhatyouwantifitbitesyouitbitesyouthatsokay.

 

[RCW]

Hi All Swapped out the HST on my l3130 with a used one / the original worked butt had a great loss of power / have it on the eng. stand/ started disassemble
both plates are destroyed picture of the rotary motor plate & swash plate - plate one completely gone/ things are a little chewed up/ but the tractor operated like this / also found a poppet lodged open with a piece the plates # 160 / all the other pieces were in the pluming & oil cooler / can't buy just the plats / it operated like this/ going to putt back together without the plates & save as a spare (THOUGHTS)

ferguson - -

I think I said it before, but SO glad you got it working again!

Now that you have the old HST apart, do you have any ideas on why the old HST went bad?

Looks pretty torn apart.....

Probably a hard question to answer. Just curious.

You've gotten into an HST more than most guys here. You seem to have a good handle on how they work. Dick B is another that comes to mind.

 

[ferguson]

noproblemyoudowhatyouwantifitbitesyouitbitesyouthatsokay.

LOL

 

[ferguson]

ferguson - -

I think I said it before, but SO glad you got it working again!

Now that you have the old HST apart, do you have any ideas on why the old HST went bad?

Looks pretty torn apart.....

Probably a hard question to answer. Just curious.

You've gotten into an HST more than most guys here. You seem to have a good handle on how they work. Dick B is another that comes to mind.

From the dealer shop guy / working in high gear full peddle engagement full throttle up against the relife valve / I E Like running a brush hog high range up & down steep hills / down hill more so then up hill puts more psi on the system ??( I have never used a brush hog on this machine ) I purchased it used ????

 

[RCW]

From the dealer shop guy / working in high gear full peddle engagement full throttle up against the relife valve / I E Like running a brush hog high range up & down steep hills / down hill more so then up hill puts more psi on the system ??( I have never used a brush hog on this machine ) I purchased it used ????

Yep, understood. I remember you bought it used. Was just curious.

 

[ferguson]

Compleatly dissambled every thing . plugs, relife valves pump, shafts & bearings even pipe fittings from case . cleaned all going to put it back together ( less those plates ) and keep as spare . Maybe find a set somewhere .

 

[ferguson]

Hi All Swapped out the HST on my l3130 with a used one / the original worked butt had a great loss of power / have it on the eng. stand/ started disassemble
both plates are destroyed picture of the rotary motor plate & swash plate - plate one completely gone/ things are a little chewed up/ but the tractor operated like this / also found a poppet lodged open with a piece the plates # 160 / all the other pieces were in the pluming & oil cooler / can't buy just the plats / it operated like this/ going to putt back together without the plates & save as a spare (THOUGHTS)

Can any one tell me what these plate do they are not machined pieces / there stamped metal with no close tolerances ???

QUESTION ON THE PLATES What do they do / they are not machined pieces there stamped metal with no cloces tolerances ???????

 

[ruger1980]

They are there to help keep the slippers aligned and in contact with the swash plate. When the slippers bounce on the swash plate all sorts of bad things start to happen.

 

[ferguson]

They are there to help keep the slippers aligned and in contact with the swash plate. When the slippers bounce on the swash plate all sorts of bad things start to happen.

Slippers?? the 9 brass ends on the plunger rods / the rods are a mechined fit & the hole unit is spring loaded when you put the back plate on there a 1/2" or so gap of spring tension / I'm unsure HOW the slippers can bounce / the plate does not hold the slippers against the swash plate ?? it fits against the plunger rod housing " I AM NOT SAYING NO " JUST NOT UNDERSTANDING " MORE INFO PLEASE "

 

[ruger1980]

In the image below the guide is outlined in red and holds the slipper feet, marked in blue, so the stay aligned and seated against the swash plates. There are 2 guides one for each rotating group.
The springs outlined in yellow hold the barrel of the rotating group against the valve plate outlined in green.

 

[ferguson]

Thank you that clears thins up picture worth 1,000 words. What do you thinked happened to cause the plates to break

 

[rbargeron]

I think the plates were collateral damage. The slippers normally slide smoothly on polished surfaces - but once that perfect fit starts to get damaged, metal bits start chewing things up, the slippers fail and wreck all of it.

Most HST's perform perfectly for a long time - yours is the unusual case. Glad you found a good used one and its working. Dick B

 

[ruger1980]

Thank you that clears thins up picture worth 1,000 words. What do you thinked happened to cause the plates to break

It's really hard to say without seeing all the parts nut as @rbargeron stated the guides are more likely a result of slipper failures

 

[ferguson]

I think the plates were collateral damage. The slippers normally slide smoothly on polished surfaces - but once that perfect fit starts to get damaged, metal bits start chewing things up, the slippers fail and wreck all of it.

Most HST's perform perfectly for a long time - yours is the unusual case. Glad you found a good used one and its working. Dick B

The faces of the slippers Are perfict also both swash plates have not a scratch in them / the backsides of the slippers are chewed up a bit . Thats it , Shoud have taken mor pictures when it was appart. Wish i could lay my hands on two of those plates ? The rest of the H S T is in great condition , Had every thing appart . Tractor ran maybe 4 or 5 hrs after noticing problum .

 

[rbargeron]

"........ also found a poppet lodged open with a piece the plates # 160 / all the other pieces were in the pluming & oil cooler ....."

The plate normally shouldn't see much force. Maybe a loose piece jammed the barrel and the torque wrecked the plate, sending scraps everywhere.