What size wrench. Large locknut on adjuster bar for boxblade

couleedude

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Kubota L2502 Tractor Package
Dec 17, 2024
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Grand Coulee, WA
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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Kubota L47 TLB, Homestead 55" grapple, LP 1684 rear blade, WR Long 84" snowplow
Nov 1, 2020
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Plus one on the adjustable! Multi purpose.
 

Russell King

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L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
Jun 17, 2012
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Austin, Texas
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.

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