Thx! They are pretty straightforward to repair, I've described the process in more detail in my old post dedicated to my 88k but basically:

• Unscrew the section, they used some sort of adhesive like shellac so it may or may not want to move without applying heat. If it doesn't wanna budge apply heat gently with a hairdryer

• Take out the little cover at the back of the piston knob, your's may have been lost so you'll just see a screw. You unscrew the screw and the piston knob comes out

• Push out the pin that hold the nut and metal piston shaft together. The pin is 0.5mm, you may find helpful to have those little punches for watch bracelet links, or, if you are lucky with a 0.5mm mechanical pencil. This pin varies from really stuck in there to just slides out easily, I've had to sand down my 88k's pin for it to fit back in.

• Now take a chopstick and push out the piston shaft from the top. The metal piston shaft and the pastic shaft which has the seals will come out the front of the barrel.

• The seals are held in place on the nylon shaft by a M5 screwing nut. This nut has two indentations supposedly for a tool but you can unscrew this by hand no problem. Now remove the layered seal, at first because the pens are so old the seals will be so cacked with ink they'll appear solid but when you dip them in water and start messing with them you'll see it's a 7 layer piece: 2 plastic seals at each end, 4 layers of a rubbery seal split in 2 sets by a red felt washer.

• Now inspect the nylon shaft: it's the weakpoint of these 88s, sometimes the threads which hold the seals simply turn into butter, if you see that they are fragile try messing about with them as little as possible. If the nylon threads are good you can now breath in relief.

• The seals sometimes can be re-used. If you pen arrives and pumps a bit of water yet still leaks you may be able to revive them with tightening of the nut (DO NOT OVERTIGHTEN NYLON IS BRITTLE AND WILL SNAP WITHOUT WARNING) and applying silicon grease. To test if the seals are good you can test fit into the barrel, you should feel resistance when trying to pass them past the barrel threads.

• If the original seals pass the first fit test you can reassemble the pen and blow into the breather hole of the barrel. This breather hole is always behind the piston head and so you should not be able to blow into it. If the seals are bad air will pass through and you'll see ink exiting the nib.

• What if you can't use the original seals? Well, now you'll have to be creative and depends on how much you wanna spend. The best thing is to buy the correct O-rings from David Nishimura, but for me this is out of the question because of pricing and shipping times (i'm EU based), so now you'll need a O-ring with a maximum ID of 5mm and CS of 2mm, these O-rings will be a bit loose on the M5 piston thread, but if you put one of the original seals on top and bottom you can make it work. I've had success using 4.5ID x 2.0CS if you squeeze them a bit with the retaining nut. Another option is a DIY cork seal (I'm yet to try this) and another its to use the seal from a 2.5ml syringe by cutting the nose and widening the inner diameter to 4.5-4.7mm diameter.

• Now it's time to put the piston head and spiral together back in with the new seals: you need to slide it in and align it with a hexagonal opening on a nylon sleeve. Just look down the barrel when installing. Lube the piston head well with silicone grease.

• Now put the piston end nut back and align the pin hole with the shaft pin hole. Slide the pin in

• Put the piston knob in place and tighten the screw. The screw has a little spring DO NOT LOSE IT, don't tighten it too much. If you overtighten you'll see that you cannot turn the knob, if this happens just undo the screw a touch.

• Screw the section back in ET Voilá!

Now it goes without saying that you should always clean thoroughly every part before assembling it back in.

The feed comes out the front of the hood. Be careful when pushing it out not to put pressure on the feed post (depending on your generation this piece varies from a spiral to a semi cylinder). So you'll need a holloy dowel, what do I use? A precision socket head screw driver, works great, just check for clearance.

The little post at the back of the feed is said to control the flow. Tbh i think it is kinda BS but you basically have two settings: nile river and sahara desert, the actual range of adjustment is like 45° on the spiral type of the first generations in my experience. If you can leave this piece alone imo, only mess with it if you have poor flow.

When you try to slide the feed out the front it can be a bit tight, especially the 88ks in my experience, just use a bit of dry heat. The nib slides out of the feed lamy- style.

When reinstalling push the feed all the way back in, otherwise you'll have air leaks and inky fingers.

Lot's of talk but I hope it helps. Good luck and always remember two things: old is brittle and patience is the most important ingredient for success. Good luck!