REAR CARRIAGE BUSHING ON HP Z3100 and Z3200 Printers
Notes on Tools, Materials, and Procedures by Mark Lindquist

Rear Carriage Bushing Replacement
HP DesignJet  Z3100 - Z3200
 
Mark Lindquist 12/10/2014 - updated --1-10-2017
 

Rear Carriage Bushing on the HP DesignJet  Z3100 - Z3200 PRINTER

By Mark Lindquist  |  August-December 2014-1/5/2017 © 2017 Lindquist Studios All Rights Reserved

HP Z3200 Rear Carriage Bushing

HP Z Series (Z3200) REAR CARRIAGE BUSHING REPLACEMENT



The rear carriage bushing (top in photo above), which is the flimsiest of parts in the printer, is easily broken.

Thankfully, Bob Wert of LPS, one of the most brilliant repair guys on the face of the earth, has come up with a super quick and easy fix for replacing the Rear Carriage Bushing.  Bob is a brilliant technician.  See the video below. Thank you Bob!

I'm leaving everything below because it's how repairing this part was done in the past, but really, skip all of it and just do it the way Bob Wert shows in the video.  While you're at it - just buy the bushing from LPS.
 

(Notes in green from John Nollendorfs:)

"Nowhere is it well documented exactly where this bushing is located and how it can be easily damaged. Before sliding the carriage off the end of the rail, the bushing is located on top of the carriage, and needs to be carefully depressed when sliding the carriage back in it's guide slot. If you can be very careful sliding the carriage off the end of the machine, you will notice the bushing, as you start to pull the carriage off the rails. Start sliding the carriage very slowly, and observe the bushing on top, as it slides out from under the rail."

Thanks for that tip John. These bushings are getting hard to find and they are easy to break. They are also becoming pricey. Here is an example:

Pricey Bushing

Rear Carriage Bushing replacement for HP Q5669-60687 on Z2100, Z3100, Z3200

A replacement is available for about 15 bucks here

An enterprising guy on eBay with the user name of "oldva"actually decided to manufacture a replacement that is beefier and much more reliable (bottom in photo above). "...tough, abrasion and impact resistant urethane and contains continuous strand carbon fiber tow running the full length of the bushing."

I ordered the bushing replacement from him and installed it and it works perfectly. Sometimes he runs out on eBay.

From his listing:

“...Last year the 'rear carriage bushing' in my Z2100 printer broke which allowed the print heads to scrape across the media it was printing on. I was lucky in that the broken part fell on the floor under the printer, so identification of the problem was easy and I didn't have to go 'digging' into the printer to recover any broken pieces that might jam things up. This 'bushing' is one of the components that set the height of the print heads over the media. Without this 'bushing' in place the print heads may contact the media, especially if printing on a thick media, such as canvas or board and leave drag marks in the print path.

I searched and searched for a replacement part, but at the time none were available, not even from HP ! It appears that this bushing is a common failure point, as I have found numerous inquires on the internet regarding it. So, "Desperation being the Mother of Invention" , I headed down to our workshop, where we do have some equipment for molding plastic parts. After noting the failure point of the old bushing, I designed a mold for a new style bushing which would correct the weaknesses of the bushing design. I have been running the re-designed bushing for a year in my printer without any more problems.

This listing is for 2 of the re-designed bushings, so you will have a spare. It is made from a tough, abrasion and impact resistant urethane and contains continuous strand carbon fiber tow running the full length of the bushing. The tabs on either end of the bushing are much thicker than stock, but the center area maintains the 2mm thickness of the stock bushing, so print head height remains correct.

Included are photo illustrated instructions of an easy method (I've had a lot of practice) of installing the bushing in a Z2100 printer, that does not require the degree of dis-assembly suggested in the Service Manual. It is still necessary to remove the cover over the right side of the printer which requires a Torx 15 screwdriver, and in addition you will need a small flat blade screwdriver and needle nose pliers or large tweezers and a good light source.

The $15 price includes 2 rear carriage bushings, illustrated installation instructions and free postage in the USA."

On Luminous-Landscape forum, a member, "Roscolo" discusses a replacement procedure shortcut:

"First, you do this at your own risk. If you need to install a new Rear Carriage Bushing, I think the odds of you screwing something up are infinitely greater if you follow the instructions in the z3100 Service Manual (take the whole printer apart) than doing what I outline below (only remove the Right Cover), but, bottom line, they tell you to do it their way. I think my way is better, but don't blame me if you screw it up.

If you replace your belt on the HP z3100 / HP z3200 it is EASY to break or lose the Rear Carriage Bushing. It is also VERY EASY to miss this problem until AFTER you have replaced your belt and reassembled your printer and find that it is dragging the heads or the carriage on your paper/canvas, streaking/smearing ink, and making some loud banging noises when the Carriage travels to the right. So when you replace your belt, double and triple check that your Rear Carriage Bushing is on AND that it isn't cracked (it is extraordinarily flimsy plastic) and you won't have to do what I did.

BUT if you need to replace or install the Rear Carriage Bushing on the z3100 / z3200, the manual tells you to essentially disassemble the ENTIRE printer just like you have to do to replace the belt. YOU DO NOT HAVE TO DO THIS (if you're careful.) Just remove the Right Cover. When you pull the Carriage all the way to the right, (use a bright light shining in there so you can see), you will see the hole where the far end of the Bushing goes and the hole where the near part of the Bushing goes (look at the diagram in the Service Manual). I just used a pair of needle nose pliers to hold the bushing so I didn't lose it, (don't let go!) and using a tiny 4 inch screwdriver (tiny like you could remove the back of a watch with it), was able to gently force the far end of the bushing into the far hole. Then CONTINUING TO HOLD ON TO THE BUSHING WITH YOUR PLIERS, push or pull back that fleshy colored piece of rubber thingy in the way, and you can easily apply tension to install the near end of the bushing into the corresponding hole. If you bend the fleshy rubber thingy a bit, use your pliers to bend it back like it was. This saved me about 8 hours of headache NOT having to tear down and rebuild the entire printer AGAIN, and eliminated the likelihood that I could just as easily lose/break the bushing again when having to put the Carriage back on!

I did this on the HP z3100. I have not done it on the z3200, but my understanding is the printers are exactly the same in construction."

The rear carriage bushing also carries oil to lubricate the carriage guide rod.
See diagram below:



The above illustration is for educational use and may be subject to copyright
 

By Mark Lindquist | August-December 2014-2017 © Lindquist Studios All Rights Reserved