Don't forget to replace the little tiny o-ring inside the shaft hole! It's not an easy one, but it's do-able with some perseverance. There'll be bad words, but keep at it! Use brass picks! You can see it in this picture:
If I can do it with my shaky hands, I think most people should be able to do it: but yep, perseverance is the name of the game
Skip, one of my weapons of choice for this job is using spit of a little dish soap: while silicone grease is a wonderful lubricant, I find it just a bit too slippery while trying to get these in. I grease them up after I get them in: it keeps sentences like, "Mother (expletive deleted)! Where the (expletive deleted) did it go?" when it shoots halfway across the room never to be found again because they can act like watermelon seeds being pinched...
It's no worse than a Mistral or MR12 o-ring. Same technique. I sometimes stick a bamboo skewer into the hole before trying to fit the o-ring back in. That keeps it from trying to squeeze out the bottom when you're fitting it through the top.
Phil- I cant say this too often here "but brilliant minds think alike", that's exactly what I was going to try. That's a good thought JB, the inside where the shaft moves is what really needs the lube.
I got all of it out. I put 4 bamboo skewers through the holes on the diaphragm side, and an old HP diaphragm on the body side (to prevent damage). I then put a C clamp over the whole contraption and used it as a press. It came apart like nothing. Now on to cleaning and assembling.
I figured it was time for an update here. I finished putting my Hydro-twin II together. That tiny O-ring wasn't too bad, I used a skewer and a plastic pick. It took 3 tries but I got it. When I put it on a tank there was some free flow, but the second stage adjustment was set too tight. I pulled the second stage out but I didn't take it apart, the seat can be replaced without taking the second stage apart. I loosened the adjustment until there was some play in the second stage lever, and then it locked up. The IP was only 40 psi, so I brought it up to between 130 and 135. Its solid as a rock. Time to figure out a hose loop for it. I'll probably use a USD/Voit set up. I wish I could get orange hoses to go with a black mouth piece, but I don't see those out there. Phil- the label on mine slipped just like yours did.