How to bolt down a Kohler tank with three bolts?

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WorthFlorida

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I replaced a toilet with a Highline Kohler with the "class 5" flush. It has the new three bolt pattern. The instructions are a bit vague. All it mentions to level the tank turning the nuts. I snugged them down with a socket on an extension and turned them buy hand, no wrench. Every thing seems OK and no leaks, but how far or tight should these bolts be. I attached the instruction and the picture shown is how it looks before the tank is on the bowl.

tank.jpg


It seems like the tank and bowl can never touch each other as in the old two bolt system and this keeps some flex between the two.
 

Reach4

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You should have three points of contact or almost-contact. These are often front left, front right, and rear. If you tilt the tank away from a point, and you can slide a piece of paper into the gap, then you should tighten a little more. You can estimate by how much gap remains how much more you will need to turn. You will need a wrench.

Do not over-tighten.
 

Jadnashua

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That design appears to have a gasket on each bolt between the tank and the bowl. So, you will not get the tank tight against the bowl. Most toilets have molded legs that act as the stops - it does not appear that this design does. As long as you get the tank so it doesn't flop around and doesn't leak, by using a level, you should be able to determine if you've got each bolt at about the same tension. Important note...this assumes that the surface of the bowl is level! It may not be, either because of variations in manufacturing or your floor that it is mounted on.

Is that gasket somewhat resilient? I'd guess it is probably a hard rubber, or something similar. You should not need a lot of torque.
 

hj

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2 bolt tanks also seldom contacted the bowl, and the ones that did often cracked eventually. If the 3 bolts are tightened properly there is NO WAY the tank can "wiggle, (that is the reason for the third bolt). IF you believe the "engineer's drawing" then you also believe you can tighten the nuts with a Crescent wrench.
 

Asktom

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Lean on the tank while you snug the bolts with something other than a crescent wrench.
 

WorthFlorida

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I called Kohler and my adjustments and tightening was right on. Below on the Kohler site they now use a new encapsulated bolt. The ones that came with the Highline Classic are similar. The major difference is just under bolt head is the same material and has a circumference larger than the threads but not as large as the head. The bowl gasket three flanges have a rubber washer to each hole of the tank are inside the bowl hole. This provides that other than the threads the bolt head cannot go through the bowl holes, therefore, rubber meets rubber and it forms a very good leak proof seal. The bolts heads do not and can never touch the bottom of the bowl. The rubber material under the bolt head will expand slightly and might just slip into the hole as in my case but that is OK. Tighten buy hand is preferred until the tank just stops to wiggle. The tank and bowl will never touch and this gives some flex to minimize the tank from cracking should it ever be leaned on. I do not have a picture of the actual bolts but the installation picture is accurate.

encapsulated bolt.jpg
Bowl gasket.jpg
 
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Reach4

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Tighten by hand is preferred until the tank just stops to wiggle.
Interesting system. It looks like it might be easier to install correctly, although the directions could use some improvement. Did you discuss the wrench shown in the directions?
 
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WorthFlorida

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I did mentioned how I tighten them by hand with an extension & socket. He did say that is OK as long as the tank is steady. There really is not much torque needed to compress these rubber like parts. I'm a big guy with big hands so it is easy for me to turn things. I think they show a wrench since it a very common tool that gets the message across with a picture. Actually, it would be very difficult to turn the rear middle nut since it is close to the wall with an adjustable wrench and it is a bit recessed. The bolts do not extend down as much as the old two bolt system where you would need a deep socket. This system is nearly bullet proof but the instructions do need more clarity.

Tonight, I was actually was going to the house where I installed this unit and take pictures but I had to go to a co-worker's home to flush out and replace part of the condensation drain for their A/C. It was plugged up and the Safety Switch was bad, therefore, not turning off the compressor. They had a lot of water overflowing inside the air handler system and onto the floor inside the home. It happens quite a lot in South Florida homes. With our high humidity and daily use the drain system need continuous maintenance. It's all in the 3/4" PVC drain lines.
 

Randy Stegbauer

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After seven more years, Kohler hasn't improved their instructions. You description is the best of the entire internet! Everybody who makes a video doesn't show the *inside* of the tank showing that the bolt heads should *not* be pressed down onto the bottom of the tank. No one describes how "snug" to tighten...except for you! I feel much more confident about installing the tank now. Thanks!
 
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