Seiko 7s26 full stripdown service, restoration and watch repair tutorial

my wife's cousin shoved this Seiko automatic in my hand a while back it was a complete non runner as you can see it looks in fairly bad shape now quite certain that this watch has never been serviced in its lifetime and so is well overdue for a complete stripped down a clean and lubrication the movement has come to a complete stop and were not whined and I'm guessing that over the years the oils and greases have dried up and are acting as an abrasive rather than a lubricant the case is quite mucky so let's start by removing some of the crud before we remove the movement from the watch case here I'm using pegwood as it's hard enough to remove dirt and grime but it's soft enough that it does not scratch or damage the stainless steel case now I've removed the bulk of the grime I can unscrew the case now I want to remove the crown and stem this is a spring-loaded setting lever so to release the stem I need to press down on the setting lever in the divot and the stem will be released now I need to remove the movement from the case and I can replace the winding crown I'm just neither hands to make it and it'll be easier to remove them to protect the polybag I can use my hand levers to lift that watch hands and they come off fairly easily next I need the dial and this dial is just friction fitted there are no dial screws so a little bit of gentle prising will allow the dial to be released from the movement then going to hands are by placing them in a dust tray there is a circlip which retains the day disk I can lift this away using my hand levers and now I can use a little bit of erotic Oh to lift away the day disk now the movement because it was not being wound automatically so I have wound the movement manually and it has started let's take a look at the performance so I'm just placing this on my time graph and I can see that it's not too good really the amplitude is rather low at a hundred and ninety something degrees and in one position is showing a + 35 second add a gain in another position is even worse so I'm going to continue to strip this down I start by removing the oscillating weight and now I'll just remove the balance assembly now the second reduction wheel and pinion is held secure with a left-handed screw so I'm just going to remove that and now I can remove the power from the watch by releasing the clickspring and with the power removed I can safely remove the ratchet wheel and as you can see it's quite dirty and it's quite clear the reason why this watch would not wind up so let's continue and we can remove the pallet fork we start by removing the cover plate which is retained with three standard screws and one small cross headed fruit screw and with the removed I can remove the cover plate and I'm advancing the calendar train so that the calendar wheel is not fouling the lower cover plate and that allows me to remove it easily I can remove the our wheel and the calendar intermediate wheel the minute wheel the day disc and the calendar driving wheel I need to remove the can opinion so I'm using my can opinion remover and now I'm just removing the plastic spacer movement ring this is clipped in place turning the move again I can remove the main train wheel bridge and this is secured with free screws comes away fairly easily so now I can remove the rest of the train wheels and the barrel not forgetting of course the clickspring that the keyless works is now exposed so the next job is to remove the keyless works the pole Dutchman Whaler held with this circlip so I've just removed that and that's exposed quite a lot of dirt and grime on the pole bearing and the first reduction whale is in an awful state underneath here so let's open the barrel and have a look at the mainspring as you can see the old lubrication is in a really poor State so I've removed the barrel Abba and I can start to remove the spring from the barrel and that's it the movement has been completely stripped down and I've cleaned all the parts and now of course it's time for reassembly now as you can see them I can start off by reassembling the Train of wheels well the third wheel and they are the center seconds wheel you no need to prepare the I'm going to just remove these shock settings are going to make sure that the jewels are spotlessly clean and once they're 100% clean I can reassemble these and use my automatic oiler and oil from the underside you and I'm applying here mainspring braking grace to the barrel wall and now it's time to bind the mainspring back into the barrel and for this I'm using my mainspring winders now I'm not 100% happy with this particular mainspring it looks pretty old and fatigued to me so I will be ordering a brand new one for this particular movement and I'll be looking for one of those to be delivered shortly but for now I just want to test the movement and see what improvements we can make in the meantime and now with the back in the barrel I can refit the barrel Arbor and I can snap the barrel lid back on so with the ambled let's place that back in with the train of wheels and now of course we also need to refit the keyless works you you you and continuing with our train wheel bridge reconstruction we're just going to refit the first reduction wheel and it's pole to the to the plate and now I can fit the plate to the movement and when I'm don't all the pivots are located in their respective pivot holes I can be secure the plate to the movement with the free retaining screws and now I can refit the ratchet wheel and the second some wheel can go back into place now testing to make sure that the the poll is doing its job now it's time to the escapement will start with the pallet Fork so I'm just placing a little bit of wind on the mainspring so that I can test the operation of the pallets and I'll lubricate the pallet stones and now I can assembly that's all good now I can remove the upper and lower shock settings and make sure that they're spotlessly clean and lubricate them and I can use my automatic oiler to do that you you now with the Esk place I just want to replace the movement ring and that just snaps back into place and I just want lubricate all the lower bearings you piñon and the minute wheel the driving for the calendar the calendar disc and the intermediate wheel the our wheel and the correct will and now I can cover plate as you can see this has the calendar jumper spring integral now I can put a plate and if you remember this is secured with three screws plus one very small cross headed screw and I can just give that a quick check just to make sure that the calendar is jumping over and that looks okay and I'm testing that date change driver will just put on the day disk now and we'll make sure that the jumper spring is located correctly and we can put back the circlip again we'll just give that a quick test and that all looks good I'm just going to demagnetize the watch right then let's give this another check on the timing machine and see where we are and as you can see that is significantly better than before the amplitude is higher but I would expect it to be even more higher than that before it was around 197 degrees of amplitude and now it's over 240 degrees of amplitude changing the position of the movement I can see that there is a slight increase in performance but I would expect this to be at a minimum 260 degrees of amplitude placing the movement on my watch analyzer I can see that there is an issue when the movement is dial down which seems to rectify when it's in the dial up position I disassembled the lower shock setting again cleaned and real Oubre gated it and now the movement is running at a much more healthy amplitude of over 260 degrees I can be happy with that especially considering how worn this movement is now I'm not going to be polishing this watch to a factory-fresh state but I do want to at least hand it back to my wife's cousin looking better as well as functioning better so I'm going to clean and buff up the case and make it look more presentable and it's probably a good idea to replace the scratched glass as well and can just reassemble the dial-in hands you I can place the movement back into the nice clean watch case to the o-ring on the crown and also the o-ring on the watch back and now I need to replace the oscillating weight the first reduction will the hole in the first reduction wheel gets aligned with the brass post on the balance coke and the center of the oscillating weight gets lined up with the winding stem and they were just that down into position and now we can do they watch back thank you for watching I hope you enjoyed that if you've not done so already please consider subscribing to this channel and if you click the bell icon when you subscribe you will be informed whenever I upload new content and if you are interested in learning more about what repair then please be aware that I have a watch repair course available via my website which is linked in the description of this video you

Channel: Watch Repair Channel

Views: 933,657

Rating: 4.9220901 out of 5

Keywords: watch repair channel, watch repairs, watch repair lessons, watch service, mark lovick, watchrepairtalk.com, watchrepairlessons.com, seiko watch, seiko 7s26, seiko automatic, 7s26, seiko skx, watch restoration, restoration

Id: tDa1ZZFwoBU

Length: 39min 3sec (2343 seconds)

Published: Mon Apr 22 2019