I recently serviced this Seiko Pogue 6139-6005 for a regular ClockSavant customer. This watch came with a number of unusual well-hidden curveballs and issues. First let's talk about screws. Watch movement screws are tiny and highly customized per-movement and per-part, with a near infinite range of variations in size, pitch, heads, specialized shoulders, and the like. If one mixes-up screws in a movement, this can produce significant work and frustration for the next watchmaker not-to-mention all kinds of running and functioning issues. Similarly, if a screw is lost and must be replaced, or it is replaced with an incorrect one, all of this can represent more work than one might think. In this particular watch, about 20 of the screws were in the wrong place or entirely incorrect and from another movement calibre all-together. Many wouldn't even tighten, some were poking-through and interfering with other parts and some lacked the proper "shoulder" to assure a part could move freely once the screw was tightened. Sorting all this out, and sourcing replacement screws, took time and was a sure sign botch was here. Next, the chronograph failed to set and reset consistently. When dealing with this issue, too often the chronograph is damaged by an impatient or inexperienced person working on it, leaving a mess to decipher. They mindlessly begin performing the wrong adjustments. In this case, fortunately that didn't happen in the past. The cause however was one I don't see as often-- a column wheel with unusual wear on it. Likely due to lack of lubrication. The column wheel is a key component of a chronograph's "programming" for start/stop and reset. If it becomes badly worn, the chronograph can exhibit issues that easily mimmic those you might find with other chronograph parts. The watch is now running nicely once again, as an added bonus, is now water resistance once again.