the Walnut Diary

I’ve spent the better part of the last week getting adjusted to the 2005 Kubota B7510 I purchased privately last weekend and trailered home. So here are some notes and a few questions. Please jump in with a comment where you have information to ad.

Towing

A few years ago I built a tandem trailer for my Polaris Ranger and usually tow it with a 4 cylinder, 4WD Toyota Tacoma, rated for 3500 pounds. The truck/trailer combination proved marginal at best for hauling a B7510 with belly mower. In hilly country I was genuinely worried about the rig’s stopping ability on the wet pavement of the day. For another trip of that duration (3 1/2 hours, one way) I will use a heavier vehicle and a trailer with brakes.

Mid-mount Mower

It’s quite an impressive implement. I spent the better part of two days on a flat garage floor adjusting the thing for a tall cut. It produces a fine mowed surface now, and the rocks are well below the cutters (ok, most of them). The vendor installed the mower by driving over it and clicking everything into place. It took him about ten minutes. To remove the MMM I slid it sideways on the garage floor. Because the mower was set to a 3 1/2″ setting, though, it lacked the clearance underneath. A floor jack raised the front enough to allow the belly mower to slide out to the right. A pair of link stoppers underneath (small plates to hold the mower arms when the mower’s not installed) proved crumbled by the hoist, so I had to remove one and take it to an anvil. The other I beat into place with a small ball-peen hammer. To hop forward in the chronology, after I had re-installed the mower and raised it once, the link stoppers were crumbled yet again. This time I removed both after a look in the manual. The problem was at the setup stage: heavy steel cotter pins were driven through the shaft retaining the link stoppers, and their bulk restricted the necessary rotation of the bits which are designed to clip onto other pins to keep them out of the way of harm from the mower mechanism. Out of curiosity I checked a 2011 B3000 at a local soccer field. Its link stoppers are also bent, caused again by too-thick steel cotter pins restricting the movement. To replace the mid-mount mower the manual calls for it to be set to the lowest possible setting. I didn’t want to do that and planned to store the MMM in a gravel-floored building, so I resolved to dig the mower into the gravel, provide appropriate blocks, and lighten the front wheels of the tractor by not removing the 405 lb. rotary mower from the 3 pt hitch. Then I removed the two flimsy metal covers on the top and drove over the MMM as the vendor had demonstrated. He was a bit better at it, but the process worked. UPDATE, OCTOBER, 2013: Turns out the best way to access the mid-mount mower is to raise the front of the tractor by chain from the car hoist. I use a choke chain off my timber skidder looped through the ends of the rear lift arms. It’s efficient and safe as long as I don’t hit my head on heavy metal while working.

Seat and seat belt

It’s impossible to mow without the seat belt fastened. Perhaps the tractor is designed that way. The seat is slippery enough I would fall off it on some of the slopes of our lawn, and without the down-force of the belt the tractor could easily flip me from the seat on full-speed, 400′ dashes to the end of the lawn. For the record, in light grass the mower cuts very well at max. cruising speed. The mower is indeed an impressive implement. UPDATE: I paid a lot of money for a new seat the parts guy and I found at the Kubota dealer. Enough’s enough. The hated original seat was actually the subject of an exchange program from Kubota a few years ago.

4WD

The extra wheels driving make treacherous slopes easy on this machine. That said, in one terraced section I did use the differential lock to get up over the top. The drive train provides seamless power in tough going, though to eliminate skid marks on corners I have learned to mow in 2WD much more frequently than I did with the Bolens. To its credit the G174 has very effective differentials, and skid marks on the lawn were never a problem until the Kubota took over.

Hoist

Is there any way to adjust things so that the mower doesn’t trail along on its front casters while lifted? (UPDATE, June 13, 2013: The centre roller is digging in on slopes because it can’t rotate around its shaft. It’s pinned in place by the hardware which trails from the front to the mower. Doesn’t seem adjustable. Must ponder this.) UPDATE: The parts guy suggested disassembling the centre roller and lubricating it carefully. Now it turns well but still digs ruts where the mower would otherwise high-centre.

Remotes

I switched the ends to fit my log splitter and tried it. Not bad at all. The splitter seems just as fast (not very) as when mounted on my 35 hp. TAFE, maybe a bit faster. My line pressure gauge reads 2600, which seems high. I tried to adjust the nut. The lock nut came loose easily, but the inner nut seemed to be soldered to the larger round end on the housing. Is the whole thing supposed to turn? I put all of the force I judged appropriate onto the end of a 9/16″ wrench and nothing moved. Perplexed. UPDATE, May 29, 2013: Embarrassed grin. When my neighbour Peter Myers dropped by I asked him about the adjustment. He looked and immediately noticed that the inside of the thing adjusts with an Allen key. A quick 1/4 turn and the pressure was at 1950 lb. and all was well. He further told me that the only thing the high pressure would damage would be a weak hose.

The Tractor

It runs very well, produces an excellent cut when mowing, maneuvers easily, provides great visibility, reasonable comfort, and an improved level of operator safety (I hope) over my elderly Bolens G174. But I still like the Bolens better. I almost never smell exhaust fumes from the Bolens, and I just like the feel/sound of the two cylinder engine better than the rather loud Kubota mill when it’s running the mower. The Bolens is a friend; the Kubota is a tractor. Now when I drive the Bolens I am very conscious of its apparent tippiness. While the ‘Bota has done all of the mowing since its arrival, both lawn and tree plantation (with 48″ rotary mower), the Bolens is still very handy for odd jobs. I don’t see selling it. Another job for the G174: I figured with the empty 3 pt hitch on the Kubota I could easily use the trailer hitch triangle to ferry trailers around the yard when mowing. But I find myself using the Bolens for the job instead. The Kubota’s range of travel on the 3 pt hitch is restricted by the MMM hardware, so it won’t reach down far enough to pick low-lying trailer couplers up off the ground.  With unlimited height adjustment, the Bolens works better for this. It also turns out it’s a lot easier for me to turn and look backwards from the Bolens seat, unencumbered by seat, belt, ROPS, and hydraulic controls mounted at my right elbow on the Kubota. So ease of turning around in the seat and the ability to reach down trumps the step-through frame, HST and power steering when jockeying trailers. So far.

Mowing under apple trees

Forget it. It’s too tall. The Roll Over Protection System stands 75″ from the ground. To mow around the trees this time I pressed the old mowers into service to do the precise job for which I bought the new one. But I’m still glad I bought the Kubota. You just never know how something new will get used until it’s been around for a while. Seems there’s still a role for the Simplicity riding mower. With its hydro drive and small stature I can insinuate it under the pear trees with minimal damage to the branches. Its engine is on its last legs, but may last a long time if it only does 20 minutes of work per week. As my neighbours all keep telling me, you can’t have too many tractors.

A final word about the use of a rotary mower with the B7510

I have spent 500+ hours operating a succession of rotary mowers on various tractors since retiring to the farm in 2004. Precise height control on the 3 pt hitch is highly desirable, though not essential. The Massey Ferguson 35’s control was pretty good. The TAFE’s isn’t bad, though it often conflicts with the loader on the other end. For mowing season I bolt the lower setting down quite rigidly and then it cuts very well with a 5′ Rhino mower. The Bolens G174 does not have height control. The Woods 3 pt hitch finish mower which came with it uses chains attached from the leading edge of the mower to the tractor end of the top link for a minimum-height stop. Correctly adjusted, these chains do a good job of regulating the cut. They are particularly useful when the operator has to lift the cutter over an obstacle and then resume. What the 2005 Kubota B7510 lacks which I understand the new models have is precise height control. I’ve now trimmed around ten acres of trees with it and it has done a very good job, but I have to reset the height by trial and error every time I move it. This is an area for improvement. I may steal the check chain brackets off the top-link of the Bolens and install them on the comparable shaft on the Kubota. If anyone knows of a vendor for these simple Woods chain plates (check chain bracket, part #23898) stamped out of 1/4″ steel, I’d like an additional pair. Kurt at Steensma Lawn and Power Equipment in Kalamazoo, MI was happy to take my order for the parts.

Update, 6 January, 2014

The B7510 starts pretty well in winter. Frigid conditions required a block heater. The local dealer provided one which replaced a twist-in plug on the side of the engine block. Note that Kubota calls for very long (to me) preheating intervals. My Massey Ferguson and TAFE both need just ten seconds to preheat, but a Kubota needs upwards of a minute in cold weather, and 20 seconds at a minimum. 15W40 non-synthetic oil works fine in winter, as well.

Update, 2 January, 2016

The Kubota’s ease of winter starting contrasts sharply to the Bolens G174’s cold-bloodedness.  Despite the rudimentary heating element glued to its crankcase, if I wish to use the Bolens in very cold weather I have to put it to bed each night beside the stove in my woodworking shop.  It’s a garage queen from ice-in until ice-out.

A false economy  24 April, 2015

When I bought the tractor it was missing one cap on its battery, the hole covered with duct tape.  By the time I replaced the tape with a plug borrowed from a Polaris battery, spilled acid had rusted the cooling tubes and radiator screen.  Two years later I found myself with a set of HST cooling tubes glowing orange from rust.  This required a thorough cleaning and paint job on the affected area.  The replacement battery only cost $89.00 from the dealer and works much better than the 10 year-old leaker in front of the fan.  Why had I waited this long to replace it?

A surprise:  the engine needs far less pre-heating with the new battery.  The thing had started well all winter, so I hadn’t suspected that the 10 year-old battery was losing its touch (apart from leaking acid out the top, of course).

Safe when others must operate it 2 December, 2017

Heart surgery slowed me down last summer. Running the Kubota was more than I could handle, so my wife decided to mow what parts of the 2 acres of rolling lawns that she could. Turns out she did most of the mowing over the summer and rather enjoyed her new gardening implement. A retired electrician returned a decade of favours by stopping by to do whatever climbing and heavy lifting required. He lifted the 5 gallon cans of diesel to fuel the Kubota and mowed under the apple trees on the steep slope. Bet did most of the rest.

Nobody removed the mower for service, though, so it went almost 200 hours without grease or sharpening. In the fall my wife even mowed 1-mile trails through the fields and woodlot so that I would have a good surface for the walks which were part of the post-surgery therapy. When I finally cleaned it up and greased the mower, it seemed not to have suffered for the neglect.

Yesterday we pressed the Kubota into service to power a medium-sized logging winch. While I did not need to skid logs with the tractor, just control the felling of a bunch of dead trees, it carried the 540 lb. weight and, with the blade of the winch dug into soft ground, had lots of pull. The B7510’s a little light for the job, as a couple of hard pulls to control the fall of tall, crooked trees produced 4 wheel wheelies. Nonetheless, the Kubota did the job safely in a pinch, without damage to anything. The short length was a real asset in this thickly forested area. Again the safety interlocks on the tractor made it safer for a visiting operator to run it.

UPDATE, 29 December, 2018

At well over 800 hours now, the Kubota has proven to be by far the most useful tractor in the shed.  Its recent implements include the 7.5 kw generator, a lightweight chipper, the lawn rake and the sweeper, and occasional bouts on the snow blower, winch, and box blade.  Last summer I actually had to repair it.  The tachometer cable failed.  The local dealer had one for $35, though I had to dislodge a mouse nest in the dash to effect the repair.