Lyman Lubesizers: Piston stuck on the threads

[Farmer&shooter]

I have a collection of all the models of Lyman sizers. Several times I have obtained old sizers where the piston was stuck on the threads so that when you turned the stem, the piston just turned. As you know, without being able to capture the piston some way, so it can screw itself up or down the stem, Houston we have a problem. So now, when I have the piston working, and out, I cut a slot in the top of the piston so that I can capture it with a screw driver to hold it should it ever get stuck again. It is a simple operation with a cut off wheel, or you might even be able to drill a shallow hole so that you could snag it with an ice pick. You just have to have some way of keeping the piston from turning. The picture is of the piston out of an old 45 I just reconditioned that had a very stuck piston. This an easy little bit of insurance that Lyman should have put in when they were made.124489

[JonB_in_Glencoe]

That is an excellent idea !

[Twmaster]

I ended up having to drill a hole all the way through the piston on the 4500 I just rebuilt. Some way to fix that built in would be grand.

Now I'll also say this, the new piston design is much better and likely to not get as easily stuck. The 'O' Rings are not concentric to each other on the new piston design.

Drilling two shallow holes 180* apart from each other so you could stick the tips of a needle nose plier into them would be a good start.

[Farmer&shooter]

Mike,

I am afraid the two drilled holes would only work with needle nose pliers if the piston was stuck fairly near the top. Often however, the piston is stuck at the bottom when someone ran the lubrisizer clear out of lube, and the piston bottomed out. In that case, the piston is WAAAY down in the bore, far out of the reach of any needle nose pliers trying to straddle the threaded shaft.


Math anomaly: If something can go back together two ways, but it will only work one of those ways, you have a one in ten chance of getting it right the first time!

Ralph

[Twmaster]

I have needle nose pliers that will reach.