What size wrench. Large locknut on adjuster bar for boxblade

couleedude

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Kubota L2502 Tractor Package
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I found the nut size on the exploded diagram, but it said 30mm and that wrench was too small. With a tape measure, it appears to be close to 1-1/2". I am purchasing a single wrench for this, not part of a set, and want to get the correct size this time.

Any idea what size that is?
 

OntheRidge

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Plus one on the adjustable! Multi purpose.
 

Russell King

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The nut or bolt size is stated as the diameter of the threaded shank. So it is a 30mm nut but the outside of the flats is larger than the shank. So the wrench size would naturally be larger than 30mm.

When most people talk about a 1/2 bolt they are often really talking about the wrench size not the bolt size so it gets confusing. The actual bolt head is usually around 1.5 times the threaded shank size.

Here is a chart showing the head size for metric thread size bolts sthat says it is about 1.8 inches across the flats. You might want to measure it with a caliper bef buying another wrench. Also larger inch size wrenches often will fit on metric heads, but that doesn’t make them correct but may round off the corners of the bolt head.

IMG_0480.jpeg
 
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Dustball

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With the size of wrench you're hoping to buy and how expensive it could be, you're best off buying a cheap digital caliper from Harbor Freight or Amazon first so you can confirm what size you need.
 
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ruger1980

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M30 is the size of the fastener shank/thread. That would make it 46 mm which is close to 1.5" Buy a 1.5" wrench from Harbor freight or a 18-24" adjustable. Just remember when using an adjustable wrench the fixed jaw should be positioned away from you when you are pulling it toward you or vice versa.
 

OntheRidge

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M30 is the size of the fastener shank/thread. That would make it 46 mm which is close to 1.5" Buy a 1.5" wrench from Harbor freight or a 18-24" adjustable. Just remember when using an adjustable wrench the fixed jaw should be positioned away from you when you are pulling it toward you or vice versa.
46 MM is 1.8 inches, not an inch and a half
 
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NCL4701

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Large Crescent style adjustable or medium smooth jaw Stilson wrench. Figure out a way to store it on the tractor full time.
 

Russell King

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There are adjustable plier wrenches from Knipex that might be really useful for your situation (which I think is adjusting the top link on the 3PH)

They are adjustable for a large size range of hex sizes. Similar to a crescent wrench with smooth jaws but pliers.
IMG_0485.jpeg
 

GreensvilleJay

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FYI an M30 bolt could have 'across flats' larger or smaller than 46mm in that chart.
there's no law that says it MUST be 46mm. have several bolts with 'non standard' flats on them.
some OEMs spec the fasteners and don't use common 'off the shelf' parts.
ALWAYS measure and never use a 'close enough' Metric on Imperial or vice versa.
 
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ken erickson

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I found the nut size on the exploded diagram, but it said 30mm and that wrench was too small. With a tape measure, it appears to be close to 1-1/2". I am purchasing a single wrench for this, not part of a set, and want to get the correct size this time.

Any idea what size that is?
I am unsure what the nut in question is? Originally I thought the "jam" nut for the adjustable top link? Not sure what adjustable bar would be on a box blade.

Reason I ask is that I have a L2501 and will be down by the tractor in the next day or two and will take my dial calipers and measure that nut for size.

If it is the top link jam nut a open ended wrench or adjustable would be suitable rather than a socket.
 

couleedude

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Kubota L2502 Tractor Package
Dec 17, 2024
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Grand Coulee, WA
I am unsure what the nut in question is? Originally I thought the "jam" nut for the adjustable top link? Not sure what adjustable bar would be on a box blade.

Reason I ask is that I have a L2501 and will be down by the tractor in the next day or two and will take my dial calipers and measure that nut for size.

If it is the top link jam nut a open ended wrench or adjustable would be suitable rather than a socket.
Yes, the jam nut on the up/down adjustment bar. Needs a wrench, not a socket.

I have vernier caliper, just not at the location the tractor is at. Large crescent, it is!
 
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ken erickson

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Waupaca Wisconsin
Yes, the jam nut on the up/down adjustment bar. Needs a wrench, not a socket.

I have vernier caliper, just not at the location the tractor is at. Large crescent, it is!
I will measure mine when I am at my land and post it here for general knowledge.

FYI, Kubota and the vast majority of tractor manufactures refers to this part as the “3pt top link”, or simply “top link”
 

NorthwoodsLife

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With the size of wrench you're hoping to buy and how expensive it could be, you're best off buying a cheap digital caliper from Harbor Freight or Amazon first so you can confirm what size you need.
^^^^^^^^ This.

Go to HF and buy a cheap caliper. And while you're there buy a couple of the biggest adjustable crescent style wrenches that they have.... if they appear large enuf.

Cheap calipers at HF are $2.99 last I checked. You don't need digital for nut sizing.
 

North Idaho Wolfman

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"adjuster bar for box blade"

If he said three point top link lock nut, I'm pretty he would get a better answer.
 

Russell King

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I will measure mine when I am at my land and post it here for general knowledge.

FYI, Kubota and the vast majority of tractor manufactures refers to this part as the “3pt top link”, or simply “top link”
"adjuster bar for box blade"

If he said three point top link lock nut, I'm pretty he would get a better answer.
OR is it the adjustable side link he is asking about?