Using Filled tires with a BH92 Backhoe

[JWR]

I’m SAYING it DEFINITELY robs power bad pulling hills in Higher Gears.
Like bush hogging & traveling Up HILLS.

You’re not going to notice it at all on flat ground OR in low range.

Dry Clutch tractors would heat the clutch way more starting off on hills being heavier.

I love fluid filled & certainly encourage it.
All 3 of my current tractors has all 4 fluid filled 90%

I even have both my 31hp Zero Mowers fluid filled for traction because I have steep banks & hills.

It definitely robs power pulling hills & way worse in thick grass.

So yes it robs HP in my applications.

I agree that things vary quite a bit from application to application. I pull a 7ft Bush Hog brand hog weighing 1500 lbs on hilly pasture, usually involving 45% slopes and in places a little over 50%. Almost none of my part of WVa is flat. Always wear a fairly heavy DL250 FEL with either my 1000lb pinch bucket or more often lately with a grapple on it. Never felt any lack of power. Sometimes have a lack of traction (with 4WD and fluid in the tires.) Of course I am never in higher gears doing this. Biggest variable in getting up and down the steepest places is the soil condition (moist, dry, hard, soft.)

 

[FatTire]

I have an L5740 with loaded tires and have the BH92 on it about 20% of the time, and previously had the BH92 on an MX5100 also with loaded tires. Never had any problems. I've asked two Kubota dealers about that note. Neither felt there was any issue, FWIW.

 

[rScotty]

I just purchased a BH92 for my L4701. In the operators manual it states " While BH92 backhoe is installed on the tractor, liquid ballast in the rear tires should be removed". That's a problem as I have my tires filled. I really don't want to remove the beat juice from the tires. There is no explanation in the manual as to why they recommend that.

My thought is the hydraulics in the stabilizers are not designed for that much weight, and it is print to relieve the company of any sort of liability should they fail. That's just a wild arse guess.

So, what's the deal?

Tim

The stabilizers are possibility. They might fail. Along with that, give some thought to what happens to the stresses on the tractor axles and rear end housing when the stabilizers lift it off the ground. The whole back of the tractor is designed to resist the axle stresses in one direction - normally the axles push up to resist the weight of the tractor pushing down.

When the tires are off the ground, all the design loads are reversed. The tires are now being pulled down by gravity and the axles become a lever pushing UP on the tractor and trying to lift the center differential with all that tire weight out there on the end of the lever.
The differential itself can probably handle that load, but how about the rear end casting?

My guess is that some can and some can't. Maybe take a look at yours and some diagrams of how it is built to get a feel for how strong that rear end casting is. Particularly the axle bearing supports. Larger ag and commercial tractors use a doubled axle bearing and wider support on each side to spread that load.

The same goes for the subframe attachement to the tractor. The subframe mount is designed for the tractor weight and backhoe forces. The load on the subframe increases a lot when it is also lifting filled tires off the ground.

Bottom line is that the warning could have to do with strength of the tractor design rather than liability.

rScotty

 

[D&D]

Does the manual mention whether if that’s with the 3 point or subframe mount? Tires touching earth or elevated?

 

[rScotty]

Does the manual mention whether if that’s with the 3 point or subframe mount? Tires touching earth or elevated?

It's easy enough to just not use the stabilizers to elevate the tires if they are loaded. Then there's no problem. And it's probably more stable that way anyhow.

 

[oosik]

If beet juice in your rear tires has any type of negative impact on any of your activities - you have a whole lot bigger problem than beet juice.

 

[FatTire]

Does the manual mention whether if that’s with the 3 point or subframe mount? Tires touching earth or elevated?

The manual is talking about BH92 with subframe mount. rScotty's comment about axle forces when rears are lifted is a good one, although on the other hand I can't think of many (any?) reports of L-series rear end failures. Most of the problems are front axle such as wheel bearings..

 

[BCLoco]

The manual is talking about BH92 with subframe mount. rScotty's comment about axle forces when rears are lifted is a good one, although on the other hand I can't think of many (any?) reports of L-series rear end failures. Most of the problems are front axle such as wheel bearings..

I just read the pre-op portion of the manual. The key is in the wording:

IMPORTANT:

• Do not add liquid ballast or any other weights to the front tires.
• While BH92 backhoe is installed on the tractor, liquid ballast in the rear tires should be removed.

They aren't concerned about fixed ballast like cast iron weights. It's the increased tip-over potential of sloshing liquid ballast that they are warning you about. And they say "should be removed" not "must be removed".

So it's not a load thing. Definitely not a rear end thing. Rear castings are designed to take loads in all direction, otherwise you'd hear of them snapping all the time. Lots of people jack up their rear ends by jacking under the drawbar support first, then putting the axle stands under. Sometimes a rear wheel comes off the ground working on torn up terrain, or if someone accidentally backs onto a rock or stump. It happens. Especially on rough snow-covered terrain, where the tires are frequently wearing heavy chains on top of the usual liquid or cast ballast.

Feel free to run them loaded if you're confident in your ability to keep the shiny side up

 

[rScotty]

I just read the pre-op portion of the manual. The key is in the wording:

IMPORTANT:

• Do not add liquid ballast or any other weights to the front tires.
• While BH92 backhoe is installed on the tractor, liquid ballast in the rear tires should be removed.

They aren't concerned about fixed ballast like cast iron weights. It's the increased tip-over potential of sloshing liquid ballast that they are warning you about. And they say "should be removed" not "must be removed".

So it's not a load thing. Definitely not a rear end thing. Rear castings are designed to take loads in all direction, otherwise you'd hear of them snapping all the time. Lots of people jack up their rear ends by jacking under the drawbar support first, then putting the axle stands under. Sometimes a rear wheel comes off the ground working on torn up terrain, or if someone accidentally backs onto a rock or stump. It happens. Especially on rough snow-covered terrain, where the tires are frequently wearing heavy chains on top of the usual liquid or cast ballast.

Feel free to run them loaded if you're confident in your ability to keep the shiny side up

If you want to argue like that, take into account how technical writing differs from legal. In technical writing like tractor manuals, when something is not even mentioned that does not imply that it is included or excluded. What it means is that If fixed ballast is not mentioned, it is simply not mentioned...period. No conclusions can be drawn at all, and certainly you can't then say, "So it's not a load thing".

As to rear end's being broken or stressed, just because something hasn't broken doesn't mean it can't. There's a reason why things are mentioned in manuals. It'a a guide, not an all-encompassing rulebook.

Exclusionary logic may work in debates, but it doesn't help hold a tractor together.

Front tires... well, that's another subject. So far we have only been thinking and discussing rear tires loading & backhoe stresses. As to front tires, that prohibition against loading front tires with fluid or with any weight is common to a lot of tractor manuals. No, I don't know why. I've wondered that myself.

rScotty

 

[BCLoco]

If you want to argue like that, take into account how technical writing differs from legal. In technical writing like tractor manuals, when something is not even mentioned that does not imply that it is included or excluded. What it means is that If fixed ballast is not mentioned, it is simply not mentioned...period. No conclusions can be drawn at all, and certainly you can't then say, "So it's not a load thing".

As to rear end's being broken or stressed, just because something hasn't broken doesn't mean it can't. There's a reason why things are mentioned in manuals. It'a a guide, not an all-encompassing rulebook.

Exclusionary logic may work in debates, but it doesn't help hold a tractor together.

Front tires... well, that's another subject. So far we have only been thinking and discussing rear tires loading & backhoe stresses. As to front tires, that prohibition against loading front tires with fluid or with any weight is common to a lot of tractor manuals. No, I don't know why. I've wondered that myself.

rScotty

They make sure to specify any ballast in the bullet point right above it, but then they forgot to put that in the second one even though you're saying it's the weight they're worried about? Come on man get serious.

If it were strictly a weight problem, they'd have mentioned it. It's a liquid sloshing concern. As in: the tractor gets a bit wiggly because you're operating across a grade, the ballast sloshes to one side and suddenly it's not just wiggly, it's going over.

As far as the rear end thing, when people start posting threads about their rear casting cracking because they jacked their tractor up, then I'll eat crow. Totally ridiculous.