replacing IBC tote valve

My rainwater harvesting system includes 5 IBC (intermediate bulk container) totes, each with a 1,000 litre (280 gal) capacity.  It was inevitable that the valve at the bottom of one would misfunction – in this case a crack developed at the handle shaft housing and water came out steadily.

This meant I had to study up on how to replace a tote valve.  The valve is removed by turning anti clockwise the ridges on the metal coupler shown below.

There are ibc valve spanner wrenches offered at around $80 which seems steep for a simple tool.  Instead I requisitioned my basin wrench tool which was able to undo the defective valve.

 

When the valve is removed you clearly see the male thread of the tank.

The thread is called a buttress thread which means the thread has one side that is vertical, the other side is inclined and a flat top and bottom.  The water exits the tank through the male thread above.  There were various female buttress threads on internet offer such as S60x6 and S75x6.  Which was the right one for me?  The “60” or “75” refers to the outside diameter in mm of the male thread or, equivalently, the inside diameter of the female thread.  The inside diameter of my defective valve is 75mm.  The “6” refers to the pitch or distance between threads – since the products on offer had the same pitch I didn’t worry about this.

I ordered the new valve through Amazon since a) I know if a problem Amazon will fix it; and b) although the product cost the same on the suppliers website the Amazon delivery charge was less.

The part arrived in 2 days (impressive) but it did not fit – the female thread was too large.  Had I messed up?  I checked and rechecked my measurements and it appeared that the valve I received was an “80” dimension rather than the “75” I had ordered.  What was frustrating was there were no markings on the valve body to identify what size it was.  With the Amazon trump card up my sleeve I called the supplier whose sales rep initially gave me a hard time but when I said that I would simply file a complaint with Amazon there was a sea change and he assured me the replacement part would be shipped that day.  When it didn’t arrive 4 days later (Tuesday) I called again and he, being adroit, thanked me for calling and said he didn’t know how to contact me (duh!) so my call was welcome and they were going to ship that day and I would receive it that Friday plus they would let me keep the wrong part for no change.  I called the following Monday and he said it would arrive that day and IT DID.  And it fitted!

So the Amazon viaduct was helpful, I was not seriously inconvenienced by the delay and I have an extra wrong sized valve which I may be able to cannibalize when the next valve fails.

Follow up

I received 2 comments – 1 below and 1 which I managed to lose, sorry, – questioning whether the basin wrench shown in the photo above could actually grasp the ridges or lugs of the valve.  So I decided to go back to the tank with my basin wrench and take photos of it accomplishing this task.  And I made a discovery – it does grasp the ridges of the valve shown in the first picture but not the ridges of a more recent valve.

Below is a pic of the basin wrench gripping (just) the ridges of the valve with sufficient force to turn it.

The reason why it works on some valves but not others has to do with the width of the ridge.  If you think of 2 ridges, one on the left and one on the right, the wrench has to extend from the left side of the left ridge to the right side of the right ridge.  So, if the ridges are equally spaced on the circumference of the valve, the wrench has to cover a lesser distance with narrow ridges (which it can) than with wider ridges (which mine cannot).  Below are pics of a narrow ridge and a wide ridge.