Modifying water hydrant head....

This post will refer back to the thread in which a water hydrant head was repaired at Wheaton Labs:   https://permies.com/t/276448/Extracting-Headless-Bolt  

The entry photo on that thread is pasted below to start the discussion and questions.  That hydrant is a Woodford and uses a set screw to enable the operating handle to raise and lower the rod that allows water to flow when open and not flow when shut off.  The set screw allows adjustment of the rod (yes??...no??) along with what appear to be other adjustment points.

Our hydrants are Merrill, from the 'Anyflow' models.  Photos accompany to illustrate the difference in the mechanisms between Woodford and Merrill.  The Merrill uses a sliding pivot connector (not threaded) over the rod, the latter generously threaded at the end.  The pivot connector is sandwiched by two adjusting nuts so that you can adjust both up and down to find the 'sweet spot' on water flow and water shut-off. Panel 1 shows this pivot connection with and without the draw straps:  Two metal draw-straps engage with the pivot connector at one end of the straps and with the handle lift points at the other end of the straps.  Thus, lift the handle and the straps pull on the connector to raise the rod for water flow as shown in Panel 2.

The problem can be seen when all is intact:  The adjustment nuts are not very accessible (the top nut not at all!).  So adjustment of flow is a PITA!  You must dismantle the whole head set-up with each small turn of an adjustment nut and reassemble just to see if you met with success.  Very laborious!  Was wondering from those with experience if it would be possible to drill and tap threads through the pivot connector so that it could accept a set screw and operate more like a Woodford and similar hydrants...?  Note that the 'Parts' photo shows the pivot connector being silver in color and that the same on my hydrant is corroded from exposure to the elements.  Would it be better to find the same or similar part in brass or an alloy that was rust/corrosion free?  Would there be a set screw with similar corrosion-free properties when screwed into the pivot connector?  Success here would save me a lot of time and may be of use to many other hydrant users.  Thanks!

Hey John. It's hard to comment constructively at a distance. This is sort of a hands-on thing. I hope you can work out a solution. Cheers!

Thanks, Douglas!  I was mostly hoping to find someone who might say "Use caution when using X, Y, or Z metals if doing such a fabrication attempt for A, B, C reasons" or even "No...you have it all wrong the way a Woodward is adjusted!...".  I know I can get brass blocks and bars either online or locally and will likley try to have a local machine shop shape a few pieces and drill and tap threads so I can give it a shot. Even if it's softer than steel, I like the idea of the brass being relatively corrosion resistant. Nice thing is that I don't have to abandon the curren.t configuration if my attempts fail.  The longer term solution at some point will be to dig up the hydrant and replace it with a new one, but I don't mind experimenting wiht some fixes in the meantime.  Thanks again....and other comments welcome as well if something comes to mind!

......Interesting!  Update to add that a different hydrant that they sell uses either the same or similar pivot connector that *DOES* have a set screw.  If the same dimensions as the one I have , I hope to order one and give it a try before going to a machine shop.  Would be good to beta-test the idea on a pre-made version.

Bad news, Good news.....

Bad news is that the part in question containing the set-screw does not fit over the plunger rod....so I will need to get it machined/drilled out to be able to do so.

Good news is an oddity.  After having been on Merrill's website a bit, an image stuck in my head.  The image was that of the handle, sold separately on one of the webpages.  Today, when I once again was trying to re-adjust the hydrant for flow and shut-off,  I had the handle in my hand and noticed something odd.  The machining of the raised part alongside the handle that engages with the lift straps was oval shaped, not round like shown in the 'NewHandle' photo below.  It had bothered me that the assembled hydrant head had so much play in the handle, but I never focues on why.  Pack rats that we are with old equipment, I recall previous repairs that gifted us with a spare handle....looking more like the 'NewHandle' photo below.  Swapping out the old odd-looking handle with the new gave instant results with stong water flow when open and complete shut-off of water when handle is down!  So one part of our problem solved, but the set-screw issue for rapid adjustment is still to be rectified.  More to follow....