Steep Slope Mowing Questions/Thoughts?

[crashz]

This weekend I picked up a mowing job for a customer. Looking at the property on Google Maps, it looked great. But its very steep. So I mowed in low range, 4wd and kept a very slow crawl, going up and down the slope, only turning when I could at the top and bottom. It did it, but my tractor struggled with the hill. Fortunately RickB' tip on setting the back of the brush mower higher that the front worked really well and the thick grass didn't slow me down.

I estimate it to be an average of 3:1. Along with the very steep hill, its pocked with gopher holes, dips and a ridge about 2/3 of the way up the hill that gets steeper. Oh and its covered in poison ivy. Some spots on the ridge could only be done by lowering the loader bucket to the ground and using it to level and stabilize the tractor facing downhill.

The whole time I was cutting, I kept thinking "I'm never doing this again!". This was the most challenging job I've done yet and will be a mark at which I measure other jobs.

Customer is a nice guy and appreciated the job I did. He also paid well and gave me a tip. And I picked up another job from his neighbor. So it looks like I will be cutting this property again. But am I damaging my tractor? I have three concerns:

- Obviously rolling over. Going up and down worked, but it feels bad going over the ridge climbing uphill. The surprise gopher holes are the killers too. I think I'm going to stake them out with stakes and florescent tape prior to the next mowing. Poison Ivy be damned.

- The steep slopes make me wonder what I'm doing to my engine and transmission. Are they getting enough oil? I keep them topped up to the highest level on the dip stick and top of the observation bubble on the trans, but is that enough? I didn't have any power loss, and no oil light (but I wasn't always staring at it nor could I see it in bright daylight anyway). Very concerned with any damage in that arena. Keep in mind that machine is using every one of the 25HP+ up and back down the slope.

- Heat. I'm literally crawling uphill for a couple of hours straight. Temp gauge stays very low, bottom 25% of the gauge. But that engine temps. How about the trans?

What do you guys think?

 

[repete]

Got pictures?

 

[deezler]

What are you mowing with, a standard brush-hog rotary cutter? 5'?

I think if your temp gauge stays low, and no oil pressure warnings occur, you're generally safe. But it's certainly rather undesirable. The oil pan should allow the pick-up tube to stay submerged at pretty severe angles. If you suck air instead of oil, you'll lose oil pressure FAST. If so, key-off and stomp the brakes to creep down to the bottom and check the oil.

Does the 2501 have a hydraulic oil cooler? Or fan underneath like some other kubotas do?

Does the hill have a less steep side? At the cost of a lot of time, you could only mow when going downhill, then drive back up around to the top. Reading that back after typing it, sounds kinda dumb.

Main thing, I think, would be to try to never do this job on a very hot day (90+). Our tractors appreciate cool temps also. I would feel around the HST circuits; you should be able to touch the HST filters without scalding your hand, IMO. But synthetic hydraulic oil can handle a lot of heat, you'll probably notice drive-ability loss before it truly hurts anything.

 

[kthompson]

When I first read your post thought wow strong grade. Then thought on it some. If I am following you it rises about 1 foot for every 3 feet. The rise for a wheel chair ramp is 12 to 1 is what I understand. So your rise is 12 to 4 if I am doing the math correctly. I did not take rulers to view that, only did an estimate and think you are fine. You may want to really measure it to be sure the true grade you are working with.

 

[oldnslo]

Most if not all engines in tractors are designed to operate at some given slope. What this slope is is usually very hard information to find. Usually going uphill puts the oil towards the pick up tube and downhill moves the oil away from the pick up tube.

No clue on where the pick up is for your HST pump though.

 

[crashz]

I really wish I took photos. Did this job on Sunday. When I do the neighbor property, I'll get photos and post them here.

Yep - 5ft brush hog. Various field grasses, some pretty thick, other areas fairly sparse. The L2501 has a hydraulic oil/HST oil cooler in front of the radiator. No noticeable heat issues, but I wasn't touching the transmission case or filters.

I will say, it never skipped a beat, and after the work was done, the tractor actually seemed to run better. I kept an eye on the dash, but also had many other items to pay attention too.

I mentioned a 3:1 slope because that is what I think it averages. There are areas where its steep, but not very concerning. I started with those But other areas had me leaning in towards the steering wheel to keep up right and not to lose traction. At one point, the tractor felt light in the front going up. Coming down, I kept the bucket on the ground at some points. The steepest part of the ridge was done by backing up to it from either uphill or down, but never crossing it.

 

[dodge man]

I think you are fine, just make sure it dry when you do it.

 

[JWR]

Geez Crashz, where to start ? I guess I'll irritate Kubota people first. I own 3 and they are great machines BUT none except their rare highway maintenance low profile units are designed for very steep ground. For starters you can't get the rear wheels far enough apart for reasonable comfort on steep ground. Two of mine are about the same size and weight as your L2501. I put 6" wheel spacers on each side of the rear of one of mine and that makes a huge difference. I use a 5ft Bush Hog on that one too. Friends did the exact same 6" spacer thing on both an L3400 and on their M6040 and considered it mandatory for safe operation. Second, from what you have told us, you are not on "steep ground" to start with. 3:1 if we interpret you correctly means a 33% slope. Virtually every old farmer in the state of WV mows something steeper than that all the time but rarely with a Kubota because of the rear wheel spacing. I consider a 40% slope routine with very little concern whether going across or up and down. A 50% slope is strictly up and down for me and anything much above 50% I just don't need to mow. Find a place you think is the steepest you have and measure the slope. Maybe it is steeper than your eyeball suggested?? Tires: Are you using AG tires or something else? Makes a big difference if you wish to avoid sliding and losing control a lot. Don't worry about engine, transmission etc. None of those things will care under the conditions you describe. [Note: some larger MF 's have been delivered, mine was, with fuel pickups that would cause the engine to starve for fuel on a 40% slope even with half a tank of fuel (!!!) That I've not seen on a Kubota.]

Anyway this is always a fun subject for discussion. Tell us more.

 

[Smokeydog]

You did it safely and what you described safe for your machine. Conditions do change with weather, time of year, limbs, saplings, holes, machinery, etc. ROPS up and seatbelt on?

Probably groundhogs not gopher. Groundhogs have much bigger holes to worry about. That’s where bigger tractors with bigger tires really helps.

Slope Is rise : run. 1:3

High hazard work should pay more. I quit doing custom work long ago. Hard to see the profit margin on small jobs.

Wheel spacers help. Have 2” on the rear of the B26. Liquid ballast in the rear tires helps with traction.



Tilt gauges help. I have run two for measuring both planes, but more interested in side slope. Mowing yesterday up to 20 degree no problem. 30 degree real tippy. Have to really watch terrain, speed and FEL position.

 

[crashz]

Thanks guys! To answer some questions:
- R4 tires
- Liquid ballast in the rear tires, gallon of Berrymans in each front.
- Good, dry conditions and south facing slope.
- I normally run my machine with the ROPS folded down. I know its unsafe, but its always on flat ground. For this job, I put the ROPS back up. No way would I do it without the ROPS up and seat belt on.
- Smokeydog, you are probably right, must be groundhog holes. My entire front wheel would fit in the hole and the back could roll over, but with a slight dip.
- Oh - did I mention the Poison Ivy? I applied a blocker (Ivy Block wipes) before mowing, applied sun screen, wore long pants and washed with Tecnu when I got home. I'm covered right now. Worst is my face and scalp!

As far as steepness, I really need to measure it. I was estimating based on known slopes That I have walked extensively. But no hard data. I feel that its steeper than 1:3 (I usually use 3:1 conversationally, but get what you mean Smokey), but I tend to be a little shy on slopes. I've never rolled my tractor, but have seen plenty of heavy equipment and trailer dumps take a tumble. I have no doubt that if I rolled, it would be violent and it wouldn't stop until I reached the road at the bottom.

I'll see about trying to run up there a getting a quick photo tomorrow.

 

[Smokeydog]

There are level/tilt apps for phones. Have cheap electronic digital angle gauge for the break press.

Tire air pressure checked.

Unfortunately have rolled three tractors in fifty years. Shameful. Growing up lost neighbors and friends to tractor related accidents. Two without ROPS. Didn’t get hurt and surprised the tractors suffered little damage. Like most accidents the cause was a combination of several things instead one big thing.

Prefer R1 tires for steep work. Have one steep slope I could come down, stop and backup with R1 tires that can’t go up with with R4. Learning to accept the R4 tires limitations on the current tractors. That slope is growing up now. Ground hogs like the steep stuff too.

 

[MHarryE]

35° engine max operating angle any direction. Going uphill half the time, downhill other half, should not be causing a problem assuming you are not lugging. Since Kubota doesn’t utilize a hydraulic oil temp monitoring system, I keep an I-R thermometer with me and check if I am concerned. Really like to see hydro components under 200° continuous but some can go higher. Steering cooler.

 

[dragoneggs]

If it is truly 3 to 1 slope (about 20deg) I see no real issues. But the sounds of it, maybe it is more? I mow up and down slopes steeper than that. Obviously you need to go slow especially if their are hole and mole hills. This would command a premium because of the added time. As mentioned. Mow dry, up and down and hopefully you can pivot on flatter ground but other than that. Make them happy and earn some money. Win/win. Oh and ROPS up and seat belt on for any slope or FEL work... ALWAYS in my book unless going into my garage.

 

[Smokeydog]

35° engine max operating angle any direction. Going uphill half the time, downhill other half, should not be causing a problem assuming you are not lugging. Since Kubota doesn’t utilize a hydraulic oil temp monitoring system, I keep an I-R thermometer with me and check if I am concerned. Really like to see hydro components under 200° continuous but some can go higher. Steering cooler.

Interesting and useful spec on the operating angle. Don’t know if I have seen that before. Same for transmission I suspect?

One of the future projects is to measure hydraulic oil temperature at the oil cooler when operating under hard use conditions like bush hogging. Bought two thermocouples long enough to reach from oil cooler to dash on the M59. Like to see inlet and outlet temperatures in real time. Got to figure out how to secure the Fluke dual input instrument. Good topic for new thread on hydraulic oil temperature measuring.

 

[rScotty]

Interesting and useful spec on the operating angle. Don’t know if I have seen that before. Same for transmission I suspect?

One of the future projects is to measure hydraulic oil temperature at the oil cooler when operating under hard use conditions like bush hogging. Bought two thermocouples long enough to reach from oil cooler to dash on the M59. Like to see inlet and outlet temperatures in real time. Got to figure out how to secure the Fluke dual input instrument. Good topic for new thread on hydraulic oil temperature measuring.

I hope you write up the hydraulic oil temperature measuring and also what you find when doing jobs. Might as well add gauges for front-to-back and side-to-side tilt while you are doing it. I'd like to put the same on our M59.

If anyone has the an engine & transmission diagram either to scale or with measurements we could figure out where the limits are.
That basic engine block used in our M59s has been used by Kubota for a lot of tractors for decades. We ought to be able to find the slope limits somewhere.

Going up and down hills can have weird effects on cooling. Going downhill the radiators are lower than the rest of the tractor, so a lot depends on whether the fluid is statified by density (hot fluid is generally less dense and floats on the cooler fluid), where the fluid pump is picking up the hot fluid, and all the rest of the things that determine how the fluid is getting pumped through the radiator.

Remember: "You have to rise before you run", makes it rise over run. I've never heard of slope described the other way around. I suggest that if slope is used the other way around conversationally, it is probably a very local usage - but difficult to change.

rScotty

 

[JWR]

Good info Crashz. Those R4 tires are not the right tool for that job. I realize what you got is what you got. R1 AG tires are much better getting up and down steeper slopes and much less likely to get you into an inadvertent slide. The liquid in the tires helps traction but does very little for roll resistance. Ground hog holes are a menace, esp if you hit one on the lower side while mowing across. Evening going straight up/down a gnd hog hole is usually not just the hole but also a dirt pile beside it and can severely destabilize the tractor contact with the ground. Ever been to the PA Ag Progress Days up near State College? They used to do a neat demo with a remote controlled tractor and a dummy in the seat on about a 40% slope. They purposely go back and forth with everything OK and then hit a hole on the downhill side which turns the tractor over into a roll. Very informative demo!

 

[crashz]

We took a ride on Friday night to the customers place. See photos. To me (and my wife, she freaked out about it), it was very steep. But the pictures make it look kind of tame. The second is the ridge I spoke of. I have a theodolite app on my phone, but didn't want to attract any attention from the neighbors, so I just quickly took these from the car. The next time I do this field I'll put the angel finder on and get accurate measurements.

Maybe I'm just being a wimp about it. i know the tractor seems to struggle with it. I bet (but didn't try) that it would not climb the slope in Medium range.

 

[crashz]

BTW - good info on the slopes that tractors typically can handle. I'm feeling more comfortable about the average of the slope and what the tractor can handle (though I may change the transmission fluid early this year).

I will be mowing the neighbors property on Saturday (weather dependent), which is a little less steep, but longer runs. I'll bring a temp gun and take some temps while I'm out there. Also get some angle measurements.

Scotty - you are completely correct about the slang of terms that are used locally or among groups. This is probably one of millions.

 

[crashz]

JWR - sounds like a great demonstration. I might never mow slopes anymore though! I'd like to check that AG show out.

 

[rScotty]

We took a ride on Friday night to the customers place. See photos. To me (and my wife, she freaked out about it), it was very steep. But the pictures make it look kind of tame. The second is the ridge I spoke of. I have a theodolite app on my phone, but didn't want to attract any attention from the neighbors, so I just quickly took these from the car. The next time I do this field I'll put the angel finder on and get accurate measurements.

Maybe I'm just being a wimp about it. i know the tractor seems to struggle with it. I bet (but didn't try) that it would not climb the slope in Medium range.

I would call that a very scary slope. Doubt if I would do it myself. Luckily I don't have any that steep that need tractoring. That's where I would call in someone with specialized equipment. Too much pucker factor & not enough safety factor.
rScotty