Schrader 888 tire valve

[Charles Reese]

What is the thread size (ID) of the Schrader 888 valve stem? I had a set of 5 originals nickel plated and now there is a slow leak in 2 of them (they held fine before plating). I assume this is the result of the threads of the internal valve gizmo not seating properly on the new plating. Thought I would chase the internal threads and see it that helps. The internal gizmos are new so that could be a source of problem as well but was afraid the originals would have dry rotted.

 

[George Miller]

What is the thread size (ID) of the Schrader 888 valve stem? I had a set of 5 originals nickel plated and now there is a slow leak (they held fine before plating). I assume this is the result of the threads of the internal valve gizmo not seating properly on the new plating. Thought I would chase the internal threads and see it that helps. The internal gizmos are new so that could be a source of problem as well but was afraid the originals would have dry rotted.

I worked for Schrader, but we were in the cylinder division. I think tire valves were not standard threads. You can by a little tool that will clean the threads and redo the seat. I think the seat is the problem. Check at a parts store or tire store.