Sia Builds & Restores
MB 14x Piston Helix Rod Repair
Here are my restoration notes for how to replace a broken helix rod on two types of resin-bodied MB 14x piston filler mechanisms...
Type 1 - "C" ring at end of rod.
Step 1
First - I hand drilled a tiny hole right next to the C ring. The idea was to make room for a hook of some sort to go under the C ring and yank it out.
Here is the dental pick I used to pull the C ring out...
Step 2
Next - once I am under the C ring, I pull!
Done!
Finally - a fully disassembled piston!
Here's a video demonstrating the above process...
Type 2 - Cup ring at end of rod.
Step 1
This rod was broken right at the end, making it harder to extract because we have nothing to pull with. So, in such cases, we need to figure out a way to attach something to the remnant rod end that will allow us to pull it out. In order to do this, here I am making a small hole so that I can insert a cork screw...
Step 2
I realized that my Dremel mounted with a washer and cork screw bit will do the job...
Step 3
The corkscrew bit will enter the hole I drilled in step 1 and grab a hold of the remnant rod end. I mount the Dremel on my wood working bench so that it holds the turning knob in place. Then I place a wrench between the washer and turning knob, and I knock the wrench downwards so that the turning knob separates from the remnant rod inside it....
Done!
This felt like a safe and controlled way to extract the cup ring.