Mowing Twelveyear old B7500HST overheating and starting to blow hydraulic hoses on LA272 FEL

[fxrupr]

n 2001 we bought the B7500 with a FEL to help me finish digging a basement under my Dallas home. I hauled around 300 yards of black clay and chalk rock out of the hole and then carried crushed rock for drainage back down in there. I had dig a ramp outside in the back yard to gain access under the 2 foot concrete perimeter beam which surrounds the outside. At some point I decided that it was time to build the outside stairway in the hole occupied by the ramp so I could no longer drive the tractor in and out.

Over the ensuing years I used it around the neighborhood grading driveways, landscaping mowing etc. In 2007 my wife and I inherited her granddad’s farm land just north of Waco Tx. and we started doing required maintenance work which had been neglected for about 50 years. Since it has lived on the land, it has mowed probably 50 acres of giant ragweed, sunflowers, mesquite and several rattlesnakes. I used the box scraper, chainsaw and FEL for land clearing doing the work of 4 laborers easily each day. I got an old cable operated posthole digger that I restored and now which works beautifully on the little old tractor. We dug 3 ponds with the little Komatsu dozer but found the Kubota tractor to be way better at cleaning up afterwards as well as loading probably 200 yards of soil which got repositioned on the property. Backing uphill with a loader bucket full of muck is something the Kubota is very good at. This puts a lot of stress on the front end, which it was definitely not designed for.

Last summer it started overheating while my wife was mowing high weeds (6 foot tall giant ragweed and sunflowers). It has continued to overheat whenever chaff builds up on the radiator. There is no reserve cooling capacity in the system so if you use it as one would expect to use a tractor, it doesn’t have much of a safety margin.

There have been some issues based on poor design, which I wanted to pass along.
Namely ;
Soft aluminum front axle castings that deform with normal use and start leaking oil. I am on my third set at 450 hours.
Inadequate oil seal at the back of the hydraulic pump allowing hydraulic oil into the engine crankcase.
There is an interlock switch which is now defying detection but which creates intermittent disconnection of the starter switch. This requires jumping the contacts on the starter bendix to get it home.
The hydraulic hoses on the LA272 FEL have all needed replacement this year since there have been 5 spontaneous leaks. Sun damage is severe.
The seat is toast with sun damage with more foam showing every time I get off.
The hydrostatic forward reverser pedal has seemed to loose any neutral position, which I am afraid, will require splitting the transmission to get at the problem.

I have been around equipment most of my adult life and have never had the issues I have seen on this tractor with so few hours. It is a great little worker but they cut corners where they should have not.

I wonder on newer models have folks seen the same issues develop?
John
View attachment 289221

 

[kevinj]

Mine has about 800 hours most of it brush-hogging and loader work.

No such issues.

 

[Iamblessed]

I just have to reply to your thread. I own a 2006 B7510 which I think is basically the same tractor as yours. Mine just turned 1100 hours a few weeks ago as I use it mostly for mowing. I would guess that mine has been used for loader work for 150-200 hours.My tractor has been trouble free except for two minor warranty issues during the first few weeks. I had way too fast a leakdown on the three point lift that was just a leaking cover and I also had a safety switch issue causing it to fail to start. Otherwise all I have done is to done regular maintenance. I have never owned any piece of equipment that has been this dependable.

My thoughts on your comments is summed up at the end of your first paragraph in your own words. You said that this puts a lot of stress on the front end which it definitely was not designed for. I believe that you purchased the wrong piece of equipment for the jobs that you required. You needed a skid steer or possibly a larger and heavier duty tractor. I live in lower Alabama and we have had one of the hottest and driest summers that I can remember and the temperature guage has stayed just slightly past the cold mark all season. I can only remember one time that it got anywhere near hot and that was within a few months after I got it and it was caused by dry grass buildup on the screen. Ever since then I always blow the underhood area off after each use with my leaf blower. I don't think that was the tractors fault because the owners manual tells us to keep the cooling areas clean. Mine has always stayed in my garage when not being used and all my hyd. hoses and the seat appear to be in excellent condition. Has yours usually been stored ouside in the Tx sun?

I guess that to sum up my opinion is to say I believe that you expected too much from the little B from the beginning and should have considered something else. I believe that my uses of these tractors are more in line with what they were designed for. Yes i have moved several truckloads of dirt, clay and sand but I realize the limitations and have not abused mine. For around 21 horsepower and about 1600 pounds of weight I think they are outstanding.

 

[ScottyChip]

John, I to have a B7510, and I have not had any of the issues that you describe. I will point out a difference that I noticed between my machine and the neighbors newer B2320, again esentially the same machine/engine. The radiator in the B2320 was larger then my B7510's. When I see a manufacturer doing this it tells me they are aware of a potential problem and are looking to fix it.

Have you checked the rad to see if there are blockages, changed the fluid? Something has changed, if it work fine and is now overheating.

Good luck, great little machines. Keep us up to date on your progress.

 

[Rusty]

My B7500 which was bought new in 2003 now has 1,470 hours. Probably 85% of those hours have been at PTO speed, approximately 2,700 rpm. The radiator screen does get blocked quickly when using the mmm, especially with dry grass, weeds with seeds, autumn leaves. Frequent cleaning is required under any of those conditions. I can mow all day with my rear mount flail mower without cleaning the radiator screen. My seat does have a hole in the cover, but the only repairs to date were to replace parts damaged due to my lack of operator attentiveness (I ran into things). My B7500 has done everything that I have asked of it, including snow removal and fel work.

 

[Egon]

HST drift:

If the pedal connections are similar to the B7100 tHere will be a plate with a v cutout for centering the HST.

The roller that rides in this v may be off the plate. There may also be a plug/ nut with screw through it that adjusts an eccentric for centering the HST.

My Kubotas B7100 had about 2500 hours on it before overheating with a clean rad would occur under heavy load.

Mine had about 1000 hours of light yard work on it before it seen the type of duty you indicate. At 3000 hours it was traded in on a used JD 4200 with #7 backhoe and mower along with the FEL.

 

[Verticaltrx]

Every manufacturer has things that they need to upgrade throughout the years. While the basic B-series machines are the same as they were back then they have changed a lot of little parts over the years as they notice problems. Also, age can be as big of factor as hours for some things. Things like seals, gaskets, hoses, tires, seats, etc just deteriorate with age regardless of the make. In fact, putting more hours on per year is probably better for those aforementioned items. As for the cooling system, I will agree. Every Kubota we own (B7610, B3200, ZD21, M9540) has a woefully undersized cooling system for the US climate. I figure some of this has to do with being imported from Japan, some of it is just due to the small size of the units and lack of available space.

 

[tractchores]

Funny that you guys mention cooling, my b2920 seems to be seriously overcooled. It takes the hottest day and hardest work to get it ti start to get to mid range temp. I was told they did something with the radiator at some point on the b's to help cool the hst. I've got a zerk to help keep the hst pedal from sticking as well (not sure if that was onnolder models).

 

[brain55]

I'm trying to figure out if this was intended to be a bashing thread, an am I the only one thread, or what. Nothing you described seems out of the ordinary for the type of work you have been doing with that tractor. You have done more work with that machine than most will see in their lifetime.

First off no CUT was ever meant to do that kind of digging, a small skid-steer would have been a much better choice. Second are you really complaining about the life of rubber and plastic components on a tractor stored outside in Texas, lastly with the overheating, just cleaning the screen will not do it, the fins in the radiator plug up with dust too and need to be blown out. If it is now overheating almost immediately it is possible you blew a head gasket or cracked a head.

Everything you mentioned is not unique to Kubota's I have been around CUT's for over 25 years there isn't one if them that wouldn't need some repair work with the amount of work you have done.

Brian

 

[DAY]

I suspect that 90% of "CUTs" do not do this much work in their lifetime!
It is like using a pickup truck- again, 90% bought by commuters/weekend warriors-to haul three loads of crusher-run a day, 5 days a week.
The CUT builders need to keep a sharp eye on the retail price, and that means building to that 90% market.