Why it is a bad idea to raise a Kubota tractor on a car hoist (UPDATED)

May 30, 2013

UPDATE: 4 July, 2014

The attached photos show a safer method of lifting the front of the tractor for mower installation.

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2 January, 2016

For two mowing seasons the chaining method illustrated above has worked without a hitch for weekly installations.  Most weeks the B7510 runs other implements on the property between sessions on the 2 acre lawn.

UPDATE ends here.

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Original article begins here:
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As long as I used the Bolens compact tractor to mow the lawns I could sharpen the blades by the simple expedient of raising the mower on the 3 pt hitch and diving underneath with my trusty angle grinder.

The rocks haven’t changed, and though I am using the newly-acquired Kubota mower at its maximum height, occasional trolls have still lept out of the sod to engage the new knives in combat. Things came to a head yesterday when a suddenly-emerging rock caught the middle knife a good one. Things sounded rough, recovered, and I made another circuit of the plot where I park utility trailers before I realized that the grass was getting a Mohawk cut with the centre blade out of action. This wouldn’t do.

A check underneath indicated that the blade had come loose, so I moved into the auto shop to effect a repair. 30 mm sockets are not common in shops. My tractor wrenches wouldn’t fit, either. Fortunately I found a specialty wrench in one of Charlie’s tool drawers and it allowed me to tighten the thing up to where it would run again.

But the cut wasn’t very good. I had to accept that the blades were dull, and that this would be a regular problem. Standard procedure involves removing the mower deck each time to sharpen the blades. The B7510 is designed to drive its front wheels over the hulking pressed-steel deck, but everything has to be set to a 1″ cut for this to work well, and I need the 4″ height.

I needed a quick and efficient method to access the blades for maintenance.

The tractor is all-tires-no-frame from the point of view of a car hoist. After not very much thought this morning I grabbed a couple of hardwood boards off a lumber pile and set them across the arms of the car hoist to provide a wooden path for the tractor wheels. I added a collection of walnut blocks to allow the tractor to climb up onto this improvised cradle on the hoist. In low range, 4WD the tractor eased into position and I set the parking brake. No problem so far.

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The standard shake of the vehicle when just off the floor proved that this was definitely not a car on the hoist. Cars lift by their frames and the metal-to-metal contact feels very solid. The tractor wobbled about far more than I liked. The tires are big and soft. They flex.

I kept my distance and ran the Kubota up for photos. I noticed that the left blade had a noticeable bend and would need to be replaced. The others were far from new.

Off I went to the local Kubota dealer, Weagant’s Farm Supply in Brockville. I showed a photo of the tractor on the hoist to the parts guy and he took all of the time he needed to convince me that I shouldn’t work on the tractor on the hoist. His line was that it would do a great deal of damage to the tractor if it fell off. He told me in the shop they always keep the wheels on the floor, and if they need serious lifting power, they bring over a portable chain lift. Big floppy tires don’t go well on car lifts, and the kind of yoke necessary to reach the frame past huge tires would be cumbersome indeed.

He suggested I hang the front of the tractor only from the hoist with a chain. This made sense, so I stole a choker chain from the timber winch and hooked it up.

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That worked fine. I crawled in and used the 1/2″ impact wrench on the 30 mm socket he sold me. The blades were changed in about fifteen minutes of work, so I may well have found my efficient method of attending to the service needs of this mower.

Comments from TractorByNet.com suggest that axle stands would be a good idea in case the chain fails. But the ones we have are much too short. I’ll improvise a pole under the front bumper. In conjunction with blocks for the rear wheels it should provide a usable device to improve the safety margin.

SAFETY UPDATE, 19 June, 2014:

During mowing season for the last year I have used the chain/hoist technique twice a week without mishap. Today while preparing to put the mower deck under the wheels of the tractor, I wound the chain around the front bumper in a more elegant manner than my usual tangle of knots. My dad used to call the knot a “cat’s paw” but I may not have tied it correctly. As I was lowering the tractor the winding suddenly let go and slid down the chain until wheels hit floor with a thump.

This provided cause for thought: once the chain slipped one link it sent a wave of shock through the chain/bumper structure which began to vibrate my tidy wrapping into a liquid cascade of chain, quickly dropping the tractor to the floor.

All of the other times I have lashed the chain to the tractor’s bumper, I have tied it untidily and irregularly. If the chain slipped a link, no matter. It just bound itself tighter. But not this time.

I’ll make up a prefabricated chain yoke to do the job and let you know. The hoist is still a great way to lift the front of the Kubota for mower installation. I just need to work on the chain part.

20 June, 2014: $27 worth of grab hooks and 5/16″ chain seems to have produced a workable solution (See above for photos). With the new hooking system it takes me four minutes to install or remove the mower.

11 October, 2016:  The chain and grab hooks have continued to do a good job over many cycles.

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2 Responses to “Why it is a bad idea to raise a Kubota tractor on a car hoist (UPDATED)”


  1. I would’ve just been worried about the hold on the chain. As long as everything was secure there’d be no issue! Otherwise it seems like you got done what you needed and noticed a few more things to get replace/fixed! Glad it turned out well. Thanks for posting!


  2. […] and not at all for garden tractors, but that is covered in another story in this series entitled Why It’s a Bad Idea To Raise Your Kubota On a Car Lift. […]


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