B26 tlb hydraulic issues

[Stonehaller]

Looking at just the parts diagrams for the B26 there is separate oil tank beneath the transmission on the B26. It appears that oil drains from the transmission housing through a flange into the tank. The filter housing is mounted on the side of the tank with an oil ring sealed fitting into the tank for pump suction supply. I suggest that you check that o ring as well as the o rings on the suction line from the filter housing to the pump. You should also verify the oil level in the tank to ensure the inlet through the side of the tank to the filter housing is flooded. Looks like there are a couple of breather hoses that go from the tank to the left side of the transmission. You may be able to remove one to verify the tank is full of oil after sitting. The parts diagram does not indicate if there are any check valves in the breather lines, but if pressure is getting trapped in the tank, it may be forcing oil back up into the transmission, lowering the tank level to where it allows air in the suction port on the side of the tank. Can't tell from the parts diagram whether the flange from the transmission sticks far enough into the tank for this to happen.

 

[100 td]

Some of my thoughts as well Stonehaller, on another Orange forum I mentioned to him to run with the filler cap open and to open breather hoses to the transmission in case oil was being held up in the transmission, but he hasn't been back for nearly 2 weeks so maybe he's up and running again? Would be nice to know the prognosis?

 

[smallorange]

I've got a 2008 B26 with exactly the same problems, just more pronounced. I can't even move mine now. I had replace all the filters with kubotas and changed the oil in the hydraulic system about 150 hrs. ago. I did put Shell Spirax oil in it tho. It all started one cold morning about -23 C. I had it plugged in with a heater on the hydraulic tank, went and started it, let it warm up for apox. 1/2 hour. Go to move it NOTHING, no drive or hydraulics at all, so I picked the front loader up and down a bunch of times with a farm jack and finally got it moving. I now park in the heated garage but it has never been the same, hydraulics getting weaker and weaker with air in them every morning, then it started puking the hydraulic oil out the vent on the transmission when I was plowing. Now I got nothing at all. I am at a loss with this thing, a new hst pump is $3200 cdn, and a new hydraulic pump is $1200. But there is no way I blew both pumps, there must be a releif valve struck or something like that. Looking in the manual it looks like a super huge job to get them out, splitting the transmission. Anybody has any ideas?

 

[Gary Fowler]

My 2009 B26 has never had that problem and I once ripped the filter housing off and lost all the oil. Replaced the housing, refilled with oil, cranked the engine and it took about 30 seconds to prime everything up so FEL worked, then HST worked also. It does whine a lot and I think the pressure relief valve needs to be shimmed because the hydraulics have gotten weaker with age, but other than that, everything is good.

 

[100 td]

Hi smallorange,
Unfortunately the most recent poster with this problem "dabadas" has not been back to let us know how he sorted his problems, I have previously PM'd him hoping he would respond to an email so we could find the outcome but he has not replied.
Puking oil out the vent could possibly be from air in the system, which of course could be the underlying problem. It sounds very similar to dabadas's problem and Curtis's problem, and I would primarily suspect something to do with a leak at the filter/filter housing, or restriction of flow due to filter. By chance do you have an electronic copy of the WSM?

 

[CurtisC]

smallorange,
Don't know about Shell Spirax but I found out early on that KUBOTA hydrostatic trannies and regular hydraulic oil do not mix. As a new owner I just assumed the oil the previous owner gave me was the right stuff. It ran ok until fall and colder temps moved in then it got noisy and hydraulics got more and more obstinate until it had run a while. After a little research and a call to the dealer, I drained the old oil ran a load of UDT until it got warm and all hydraulics had been exercised (to flush out the bad oil) then drained it and put in a load of Super UDT. I used the UDT to flush because properties were close to Super UDT but it was a lot cheaper. That quieted the whine and performance was back to normal. Bottom line I don't skimp on oil and have always used Kubota's liquid gold ever since.
Since my original post I ran the tractor a couple of times in February on fairly warm days (morning low in high 20's moving quickly into 50's) and it was better but still noisier than I'm used to until things got warmed up. Brought it back to Florida for a couple of projects and warmer temps (nothing below mid 50's at startup) and everything is back to normal. I have not gotten around to changing out the Hydraulic filter off of the reservoir yet and may not until next fall and its back up North but I'm still hoping I got a bad WIX filter that is somehow more restrictive with cold fluid than it should be.

 

[smallorange]

smallorange,
Don't know about Shell Spirax but I found out early on that KUBOTA hydrostatic trannies and regular hydraulic oil do not mix. As a new owner I just assumed the oil the previous owner gave me was the right stuff. It ran ok until fall and colder temps moved in then it got noisy and hydraulics got more and more obstinate until it had run a while. After a little research and a call to the dealer, I drained the old oil ran a load of UDT until it got warm and all hydraulics had been exercised (to flush out the bad oil) then drained it and put in a load of Super UDT. I used the UDT to flush because properties were close to Super UDT but it was a lot cheaper. That quieted the whine and performance was back to normal. Bottom line I don't skimp on oil and have always used Kubota's liquid gold ever since.
Since my original post I ran the tractor a couple of times in February on fairly warm days (morning low in high 20's moving quickly into 50's) and it was better but still noisier than I'm used to until things got warmed up. Brought it back to Florida for a couple of projects and warmer temps (nothing below mid 50's at startup) and everything is back to normal. I have not gotten around to changing out the Hydraulic filter off of the reservoir yet and may not until next fall and its back up North but I'm still hoping I got a bad WIX filter that is somehow more restrictive with cold fluid than it should be.

Well I figured it out, DO NOT RUN ANY OTHER TYPE OF OIL EXCEPT FOR THE KUBOTA OIL!! AND RUN KUBOTA FILTERS TOO. I blew the bushings in my hydraulic pump, and it was sucking air into the system from the front pump seal. As I look back now the oil and filters are the cheapest part of your maintenance so it was really stupid to try and skimp on that. That super tech walmart oil is crap too, I wouldn't run that in my oil furnace, unless you want to pay, and have a week on down time.

 

[Gary Fowler]

I run Kubota filters but only because I am too lazy to research what is needed for off brand types. I say this because I am sure Kubota doesn't make their filters OR the Kubota brand oil, so if one can research and find who makes these products for them, then buy from a supplier rather than a Kubota dealer, you would be getting the same product for 1/2 the cost. As for Kubota SUDT oil, my Kubota dealer doesn't even stock it for Southern Arkansas because our temps don't get low enough to require it. He only stocks UDT (at least as of a year ago) but I only used that one time in my RTV. Last oil change I switched to a Universal hydraulic oil that meets or exceeds Kubota UDT standards and I cant tell the difference in performance or whine from the UDT oil.
I also doubt that the oil smallorange used had anything to do with a seal going out unless it was not the recommended viscosity, in which case it wasn't the oil's fault, but the users for not using the right oil to start with. If you want to use regular dino oil like Kubota's UDT, then any other universal oil with the same specs is not going to cause you any problems. If you want to use a synthetic, then any other synthetic is going to be just as good as Kubota oil at half the price.
IMO, folks who buy based on price and from only a dealer are not getting anything better, just more expensive which benefits only the dealers.

Making a statement that Super Tech Walmart oil is crap is sure contrary to testing results that I have read which puts Super tech up near the top of Dino oils in both motor oil and hydraulic oils. However if you want superior synthetic properties for low temp services, you have to go with something different. DONT compare apples to oranges and then say the apples are crap.

PS> I don't use Super Tech oils but I would not be afraid of damage to my equipment if I did.

 

[smallorange]

The Shell Spirax oil that I used is as close to the Kubota oil as I could find, It is a very good quality oil, that meets all the specs for all of the compact tractor manufactures. Alot of the guys here working in the bush run that oil in their machinery and get 30,000 to 40,000hrs. out of them. All you guys down south could run cheaper oil without a problem, because it doesn't get cold enough, There are 2 different grades of it winter and summer and I had the correct grade in. The Kubota oil is just superior. My machine has about 2400hrs on it without problems on Kubota oil, but then I got cheap and ran into problems. The Wal-mart band oils are junk, I have seen it first hand with their outboard oils.The old saying is true you pay for what you get. If you have a $40,000 tractor an extra $100 at oil change is worth it in the long run. It was my fault that the pump blew, I should have had Kubota oil.

 

[100 td]

I blew the bushings in my hydraulic pump, and it was sucking air into the system from the front pump seal.

Since there appears to be quite a few instances of this problem on the forums can you expand on that a bit more, with regards which bushing and why? Just wondering if the front seal on this pump is not up to the job, and allowing air in over time, allowing wear to front bush, or whether the front bush is poor and wearing causing movement in the shaft which in turn allows air in past the seal?

 

[smallorange]

Since there appears to be quite a few instances of this problem on the forums can you expand on that a bit more, with regards which bushing and why? Just wondering if the front seal on this pump is not up to the job, and allowing air in over time, allowing wear to front bush, or whether the front bush is poor and wearing causing movement in the shaft which in turn allows air in past the seal?

What happens is the pump is mounted on the engine and turned by the timing gear, and there is about a 3/4'' steel line running from the pump to the oil tank, it is connected to a rubber elbow with two spring clamps, this is the suction side. In colder weather the cheaper grade oil will be like molasses in the line. As the engine and pump warms up the hot oil that was in the pump on start up gets pumped out. Because the oil in the suction line is so thick, the pump can't suck the oil up, therefor your pump is running without lubrication wearing out the brass bushings in the pump. (I think there brass haven't pulled mine apart yet) So once the bushings are worn the shaft wobbles and sucks in air. This all happens in about 10 minutes. The tolerances in a hydraulic pump are so tight that any bit of wear makes a huge difference. So even if you have a heater on your tank like I did, you still run the risks of burning up your pump. The Kubota oil is specially formulated for cold operation, and it does not thicken up, they already figured all that out for you and they know not everybody lives where its warm. I have also been told that as the tractor ages the rubber elbow attaching the line to the pump develops cracks in it and possibly suck air in. I spoke with 3 different Kubota mechanics and they all told me the same thing better stick with Kubota oil in a Kubota, other equipment it doesn't seem to matter as much. I learned all this the hard way, in spite of being a mechanic myself.

 

[CurtisC]

smallorange,
Good to know, given my circumstances if its the pump I'd guess I'm not as far along as you were but headed that way. Just curious, looking at the parts manual there's 8 bushings - a front and rear pair on fwd (main output) chamber and front and rear pair on power steering output. Were just some of the bushings gone or were they all bad? I haven't checked with dealer, but do they sell a rebuild kit at least for the seal and soft goods or did you have to by each part individually?

 

[100 td]

Thanks smallorange,
While I don't have a B26 (B21) I have a few problems I'm trying to sort, but am genuinely interested in the outcome and will be awaiting the pics of your pump pulled apart! (I think I may order new seals and bushes for my own pump as a general maintenance item) Also of course it's great for others in the future to be able to search for similar info which actually leads to a resolution.
However, I'm wondering if the bushings are wearing prematurely and then allowing the seal to be worn and allow air in, then at very low temps or after filter change with a filter full of air it exacerbates the problem leading to further failure.
And as you had a heater, I suspect it was not to do with the viscosity of the oil, the seal was already leaking.
How many hours on your machine?

 

[100 td]

CurtisC,
If it were me, I would replace all bushes, side plates, rings and seals in both sections of the pump. I'll have to get around to doing that on mine, only single pump though. From the quick look at parts prices(for mine at least), very cheap in the scheme of things. Hopefully smallorange will post detailed pics of his pump when pulled apart.

 

[CurtisC]

CurtisC,
If it were me, I would replace all bushes, side plates, rings and seals in both sections of the pump. I'll have to get around to doing that on mine, only single pump though. From the quick look at parts prices(for mine at least), very cheap in the scheme of things. Hopefully smallorange will post detailed pics of his pump when pulled apart.

Agreed, pump rebuild also a good time to replace the 90 deg. suction hose. Performance is still good as long as its not too cold out so its just a question of when. Using smallorange's logic (which makes sense) its a slippery slope when you have pump wear and cold weather combined.
I saw smallorange talk about a tank heater - North Carolina mountain winters are usually not that harsh but there are cold days and a tank heater sounds like good insurance to future problems (waiting for a pump that doesn't like cold oil to warm it up seems counterproductive). It looks like the type that bonds to bottom of the tank is about the only way to go - anyone got any input on best approach for the B26? Total oil capacity is about 7 gal. if memory serves.

 

[100 td]

I don't know what temps you get down to, but if you put a 4 quart container of oil in the freezer over night and you can pour the oil out of in it the morning then you know your oil is OK down to 0F at least. I'd say premature wear in the front bush allowing the front seal to suck air is probably a bigger problem, and I'd hazard a guess that this is the actual underlying cause of the problem. (smallorange has 2400 hrs on his)
Don't let me dissuade you from a heater though, it certainly cant hurt.

 

[CurtisC]

I don't know what temps you get down to, but if you put a 4 quart container of oil in the freezer over night and you can pour the oil out of in it the morning then you know your oil is OK down to 0F at least. I'd say premature wear in the front bush allowing the front seal to suck air is probably a bigger problem, and I'd hazard a guess that this is the actual underlying cause of the problem. (smallorange has 2400 hrs on his)
Don't let me dissuade you from a heater though, it certainly cant hurt.

No disagreement, front seal and bushing wear seems most likely cause probably accelerated in my case by the pump being run early in its life with wrong viscosity oil (too high). Morning temperatures on days I had worst pump performance were around 10 deg. F. Warmer incoming oil on a cold morning should minimize cavitation or air intake maybe getting me through another winter before tearing the pump down. I'd also think a tank heater in cold climates along with always using the correct oil would help extend the life of a new pump. As you said it couldn't hurt.

 

[art]

Being a dealer I will they to bring across a point. I have listened to farmers who have to run a tractor or two every day come in after a cold day and say the tractor was fine but when I started it this morning I had no hydraulics. I let it run and after an hour they started working but not like normal and feeling a lack of performance. They starved the pump.
Many oil changes are spread to far because of the cold that often gets condensation in the oil during the winter. This excess moisture lays in the bottom of the oil galleries and normally where your hydraulic oil pick-up is.
As far as oils go I like some factory oils but not many! Very few generic oils have I trusted.

 

[smallorange]

Being a dealer I will they to bring across a point. I have listened to farmers who have to run a tractor or two every day come in after a cold day and say the tractor was fine but when I started it this morning I had no hydraulics. I let it run and after an hour they started working but not like normal and feeling a lack of performance. They starved the pump.
Many oil changes are spread to far because of the cold that often gets condensation in the oil during the winter. This excess moisture lays in the bottom of the oil galleries and normally where your hydraulic oil pick-up is.
As far as oils go I like some factory oils but not many! Very few generic oils have I trusted.

That's what happened to me, I starved the pump, I should have had a heater on the steel line coming from the tank, and I should have had Kubota oil in it. The Shell Spirax is a good quality oil but does not have the same viscosity as Kubota. I plan on rebuilding my pump and keeping it for a spare, for now I bought a new one.

 

[dabadas]

Be careful replacing the rubber elbow. I replaced my pump and elbow and when I would rev the engine it start making a noise. Come to find out it sucking it shut causing the pump to start cavitating and whinning. Put the old hose back on problem solved. I couldn't squeege the old one but I could the new one.