Red=Remove, Green=Look
1- Remove the cover on the end of the rail to expose this.. the screw from the cover actually holds the tensioner restraint in the place. Remove this restraint to let the spring/tensioner out. From there you should be able to remove the one screw above the wheel to take the whole tensioner assembly off and give you all the slack you need to pick the carriage up off the rail.
You don't have to take the whole assembly off the printer, just lift it up off the rail by tilting the front up and lifting it off.. then set the front of the assembly down on the platen and let the gold rear part of the frame rest on your rail. I do all of this on the removable access station on the left side of the machine, this makes it easy to work around the head. There is no reason to disconnect any hoses or electrical connections except for the encoder strip reader.
2. Remove all screws (red arrows). The top four hold the ink/air line bracket. The bottom 8 remove the back plate.. taking off the back plate also means the belt will come free from the plate.
3. To remove the height adjusters, you'll need to hold the nuts in place while you turn the bolt. Don't lose the two belt clamp things. There are five bolts that the trolley plate slides up and down on, they will need to be removed to remove the trolley. Also note the ribbon cable, it is removed from the board, you will see it when you remove the carriage cover.. just use needle nose pliers to pop up the clip and the cable should slide out easily.. it's a tight spot.
4. This is the side of the trolley that is up against the carriage assembly.. Note the two adjustment screws for the encoder reader.. don't mess with them.. if you need to adjust them do it before you put it all back together.
5 & 6. To remove a bearing/wheel from the trolley, pop it out with screw drivers by putting them in and rotating them.. Don't nick the wheels when you're doing this. By wheel I mean the hard plastic ring on the outside of the bearing.
7. It should come out in one piece like this.
8. To remove the post, lay the bearing in something that will allow the post to hang through, and knock it out with a punch and mallet... I used holes in the trolley plate to show you.. works fine.
9. This is the bearing seperated from the post.. note the post has a rounded side and a squared side.
** From here I don't know about replacing the wheels on the bearings, I took this to a machine shop because my wheels were bad. **
10. To put the post back in the bearing, you will put the squared end into the bearing (the bearing is rounded).
11 & 12. With the squared end in the bearing, hold the post between your fingers and tap it with the mallet until the post is flush with the other side..
13 & 14. To reinstall, just press it with your finger as far as you can. You can then use your punch to tap it the rest of the way in.. the bearing should be as far down as it can go.
15. If your post is loose in the trolley you can use your punch to make a dimple in the aluminum.. this will hold the post in place.
16. Bags of bearings! Replacing a bad bearing is just a matter of having one pressed in place, but replacing a broken wheel is something I haven't solved.
Good luck.
I'm sure there are better ways to do this, but it works. I know this machine inside and out so feel free to ask more questions.