# Kioti 3510SE HST with 4030 loader, bolt torque



## StudeHudson (11 mo ago)

Hello all, just purchased a new 3510SE HST with 4030 loader. 
After reading about the loader arm mount bolt issue on several forums, I asked the dealer 
what the bolt torque spec is and do you use loctite when installing them. He told me that 
there was no torque rating, he just tightened the crap out of them and don't use loctite. 
After getting it home and going thru the loader manual, I could not match the bolt head casting
figures (YK 9) to the torque charts in the manual, so I got in touch with Kioti customer service. 
Their response ------
I spoke with our product support department. Our rep investigated and determined that the correct torque spec for the 4030 loader mounting bracket bolts is 106-127 ft lbs. He also recommended using red Loctite when installing the bolts as well as checking the torque every 10 hours.
**this matches the #14mm -8.8 bolt specs in the manual.


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## sixbales (May 18, 2011)

Hello StudeHudson, welcome to the tractor forum.

Are the mounting bolts #14mm -8.8 bolts? If so follow the manufacturers specs. And use loctite on the threads.


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## SidecarFlip (Mar 25, 2021)

Apply 272 high strength threadlocker to previously cleaned (with brake cleaner) bolts and threaded recesses, apply threadlocker, torque to spec and forget about them. 272 won't let them back out, ever. Bedises, unless you heat them up, you won't get them out anyway.


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## Thunderbritches (Sep 7, 2021)

StudeHudson said:


> Hello all, just purchased a new 3510SE HST with 4030 loader.
> After reading about the loader arm mount bolt issue on several forums, I asked the dealer
> what the bolt torque spec is and do you use loctite when installing them. He told me that
> there was no torque rating, he just tightened the crap out of them and don't use loctite.
> ...





StudeHudson said:


> Hello all, just purchased a new 3510SE HST with 4030 loader.
> After reading about the loader arm mount bolt issue on several forums, I asked the dealer
> what the bolt torque spec is and do you use loctite when installing them. He told me that
> there was no torque rating, he just tightened the crap out of them and don't use loctite.
> ...


Hello, I too just received a new CK3510SE with the KL4030 loader. Kioti doesn't come right out and tell you what the torque should be, but they do in a beat around the bush, interpretation process. In your loader manual, section 12 is a torque table and Section 13 is a parts list that lists the size of every bolt on the loader. The loader mounting bolts are 14mm and the torque is different depending on the grade of the bolt. That can be determined by looking at the number on the head of the bolt, 8.8 is about the same as Grade 2 SAE, 10.9 is about equivalent to Grade 5, and 12.9 is about a grade 8 bolt. the torque range is a low of 106 for the grade 2, up to a high 179 for grade 5 & 8. 

I'm an old dog and was taught not to use a thread locker when torquing bolts. A light coating of engine oil on the threads will give you a correct torque. Once everything is torqued, mark the head of the bolt and corresponding surface with a paint pen, to allow for visual confirmation the bolts aren't backing out. Use of thread locker is tempting, but any future torquing of bolts will not be true due to friction caused by the locker. Have fun with it, whatever way you decide to go. Mike


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## StudeHudson (11 mo ago)

Thunderbritches said:


> Hello, I too just received a new CK3510SE with the KL4030 loader. Kioti doesn't come right out and tell you what the torque should be, but they do in a beat around the bush, interpretation process. In your loader manual, section 12 is a torque table and Section 13 is a parts list that lists the size of every bolt on the loader. The loader mounting bolts are 14mm and the torque is different depending on the grade of the bolt. That can be determined by looking at the number on the head of the bolt, 8.8 is about the same as Grade 2 SAE, 10.9 is about equivalent to Grade 5, and 12.9 is about a grade 8 bolt. the torque range is a low of 106 for the grade 2, up to a high 179 for grade 5 & 8.
> 
> I'm an old dog and was taught not to use a thread locker when torquing bolts. A light coating of engine oil on the threads will give you a correct torque. Once everything is torqued, mark the head of the bolt and corresponding surface with a paint pen, to allow for visual confirmation the bolts aren't backing out. Use of thread locker is tempting, but any future torquing of bolts will not be true due to friction caused by the locker. Have fun with it, whatever way you decide to go. Mike


I read the two torque tables, problem is that the bolt heads have YK 9, which does not match up with the numbers on the table. Here is info off the Fastenal site concerning bolt/nut grades
metric  Class 8 - This is a metric nut grading similar to the SAE grade 5 classification, which is used in conjunction with Class 8.8 bolts. This is a medium strength nut.
I pulled one and cypered it at M14 x 1.5 pitch. So it seems to match the 8.8 class and 116 ft lbs torque. 
(106 + 127 =233 /2 = 116.5 ft lbs)
I will also mark each one for a quick inspection after use. 
Some interesting info I found on the Practical Machinist forum concerning this subject--





Torque Specs and Locktite - Page 2


It is the same I have had very good luck sealing things... I don't know how well it locks fasteners but it seals small holes well....



www.practicalmachinist.com





Many thanks for the replies, it has been quite a learning experience. For those of you wondering, here is the background. The reason we have no engineering data or approved procedures is that this is a restoration of a somewhat rare pre-WWII era aircraft and the data doesn't exist. Our engineers are having to reverse engineer stuff. We have elected to use MS/NAS high strength internal wrenching bolts in this application as there are several recorded failures of whatever low strength cut thread bolts were originally used. The aircraft MS bolts are rated at an ultimate load of 186 000 psi - about that of a Gr.8 bolt. Their real appeal though is not their strength, but their amazing toughness and fatigue resistance. (at a cost, about $45 for a 1/2" by 2" long bolt!) One limitation is that in this application they are threaded into a 4130 steel fitting and this limits their torque. Our bolting engineer calculated that the 58ft. lb torque would provide sufficient bolt pre-load and clamping pressure. It was his suggestion to consider Locktite or sumsuch. He correctly pointed out that with high strength fasteners torqued to the correct pre-load, galling of the threads is all but impossible to avoid. This is why thrad lubes are used in many high strength applications such as ARP engine bolts, etc. His other comment is that ordinary screw threads are not airtight and that corrosion can occur. This is due to the thread only bearing on one side of the "V" form with a small cavity on the back side. Obviously, the higher the class of thread, the smaller the cavity. Still, if normal threads were airtight/watertight, pipe threads would not need to be tapered!

Now the really interesting part. A Locktite rep saw this post and contacted me. (Thanks Lindsey) Very interesting long chat. He confirmed that a test setup would be best but mentioned that the low viscosity Locktite products were deliberately engineered not to be too lubricating so as to not screw up published torque values. He said that they behave much like a very light SAE 10 machine oil with a k value of around 0.15 plus or minus. He said that the more viscous products are more lubricating. He said that if the common low viscosity products are applied on the threads only, a torque reduction of about 10 -12 % is about right. The thicker stuff that I am contemplating is between 15 and 20 %. (This is from dry bare steel, not plated steel.) He also mentioned the fact that it is poor practice to tighten Gr.8 and stronger fasteners dry and confirmed the corrosion potential in threaded fasteners. It is a big issue in the oil and nuclear industries.

Tonight I welded a 1/2" Gr.8 bolt to a piece of 4130 the same thickness as the engine mount. After tightening it once to allow the threads to make friends, I repeatedly torqued it to 58 lbs and measured both bolt stretch and angular rotation. I then applied low strength Locktite to the threads only and torqued to the same bolt stretch and angle. Voila, 51 pounds. 

(8.79% torque reduction for the proper bolt stretch)


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## StudeHudson (11 mo ago)

Here is a good comparison chart from McMaster-carr for SAE and Metric fasteners


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## SidecarFlip (Mar 25, 2021)

Only thing I use low strength threadlocker for is things I want to take apart at a later date. ....and, it's threadlocker not Lock Tite. Locktite is a a brand name.


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## StudeHudson (11 mo ago)

More info about lock washers-








NASA: Split Lock Washers Are "Useless"!


"I know we have a problem with loosening but I don't understand why..




www.linkedin.com




First off, please do not use split lock washers to prevent loosening - don't.


SidecarFlip said:


> Only thing I use low strength threadlocker for is things I want to take apart at a later date. ....and, it's threadlocker not Lock Tite. Locktite is a a brand name.


Of course, I use the term "Locktite" as that is a reference most people are used to and understand.
I use their blue product for most stuff I work on.








Red or blue, we’ve got the right threadlocker for you!


New to threadlockers? Everything you need to know about types, application and removal.




www.loctiteproducts.com


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## SidecarFlip (Mar 25, 2021)

I have almost every grade of it here in the shop in 250 ML (expensive) bottles. I only use the Locktite brand. I believe the last time I bought a bottle of 272 high strength is was 150 bucks and I have their cleaner as well but usually I use brake cleaner as it's much less expensive. Threads must be free of oil or other contaminants for them to work properly so they don't work on wet torqued fasteners like wheel retention nuts for instance. Only dry torqued fasteners.


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## StudeHudson (11 mo ago)

More info about lock washers-








NASA: Split Lock Washers Are "Useless"!


"I know we have a problem with loosening but I don't understand why..




www.linkedin.com




First off, please do not use split lock washers to prevent loosening - don't. 

I remembered having read the NASA paper on split lock washers some time back. 
I decided to set my torque wrench at 115 ft lbs and check the bolts torque that the dealer had installed when
mounting the front bucket brackets to tractor. Half of the bolts were under torqued from 1/4 to 1/2 turn. 
I torqued them all to 115 ft lbs and applied a mark with a paint marker so that a quick visual check can be made. 
I also ordered some wedge style lock washers to install in place of the split lock washers.








McMaster-Carr


McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.




www.mcmaster.com


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