asked Jun 28, 2009 at 1:18pm
Hp HP Color LaserJet 2840

2840 printer problems

My HP 2840 color laser prints a multi-colored strip on the right side of the page. Getting worse and just replaced all ink and drum about 2 months ago...any thougths would be appreciated.

Hi. I've been having similar problems with magenta dots and yellow lines. I've cleaned the printer as much as possible. Do you suppose these are caused by drum problems? I have plenty of toner in the cartridges and don't want to replace those yet if I don't have to.

by Tri4Life on Nov 4, 2010 at 2:53am Add comment
Remove the drum and flip up the cover and see if the mark is on the drum roller. If it is the drum is bad.
by dmzcompute on Jun 28, 2009 at 6:44pm Add comment
Generally if the drum all colors are effected. Remove the magenta toner and the yellow toner and wipe off all the toner from the roller and turn the roller and wipe again. Sometimes you get some foreign matter on the black roller which moves the toner so there is a raised spot(s) which cause issues. Cleaning the roller sometimes removes those items.
by dmzcompute on Nov 4, 2010 at 4:00pm Add comment
Generally if the drum all colors are effected. Remove the magenta toner and the yellow toner and wipe off all the toner from the roller and turn the roller and wipe again. Sometimes you get some foreign matter on the black roller which moves the toner so there is a raised spot(s) which cause issues. Cleaning the roller sometimes removes those items.
by dmzcompute on Nov 4, 2010 at 4:01pm Add comment
My printer was working fine until the black toner cartridge
was used up. I replace the black toner cartridge immediately,
but now I am getting only about 40\% print coverage on a page
on the right hand side. I ran numerous pages thinking the
image drum need to adapt to the new black toner cartridge.

I bought an new imaging drum and install it. This helped a
slight amount and now I have 50\% page print coverage on the
right side.

Any ideas on what to do?
by webtex1 on Nov 24, 2010 at 8:13am Add comment
Your post is not very clear. When that model has problems printing on the right side, it's because the carousel gear has gotten out of alignment. I just got done aligning one so I'm fresh on the procedure. The cause is remanufactured cartridges. The printer I worked on had all remans in it. The magenta and yellow toners were both extremely hard to turn and caused the carousel to jump out of alignment. I came up with a quicky fix that doesn't involve hours of disassembly. I would suggest you pull out the black toner and try and turn the gear on the end. If it's stiff, then get back to me and I'll tutelage you on how to realign it.
by moe on Nov 24, 2010 at 1:49pm Add comment
The only tool you'll need is a large paper clip. Open the cartridge lid. Look on the right side near the top. You'll see a blue triangle. Just above it is a square cut out. Straighten out one end of the paper clip and stick it down along the bottom of the cut out. You will feel something release. That's the carousel brake. You can now spin the carousel around and remove all the toners. Line up the blue triangles on the sides of each toner color with the blue triangles on the toner slides and lift them out. The weight of the remaining toners will cause the carousel to turn, so you'll have to hold it so you can pull them out. It's not easy, but you'll figure it out. Once you have all the toners out, get a flash light. Turn the carousel to the black toner position. Now look over to the left toner slide. To the right of it, you'll see a white gear. There are 2 small plastic pins on it. On the big black carousel gear, there is a vertical line etched in it in the black cartridge area. You want to turn the carousel until the line is pointed at the center of those 2 pins. The left cartridge slide should be aligned with the track on the black cartridge. If you look at the right side, it will be off a bit. To realign it, grab the black carousel gear with your fingers and pull towards you while holding the left side stationery. Then move it in the direction it needs to go until it's close to alignment and let go and then push it outwards until it seats in place. Check the alignment of both ends and make sure they are close. If not, repeat until they are. I had to do the last one a few times until I was satisfied. Then reinstall the toner cartridges, making sure the colors match up with the colors on the carousel.
by moe on Nov 24, 2010 at 2:13pm Add comment
moe this works great thanks again!

I followed the steps to realign the carousel gears, put the cartridges back in, and BINGO.

by gungadin on Sep 29, 2011 at 10:39am Add comment
Ok I am about to Throw this HP 2840 all in one color laser printer off a 20 story building. For about 6 months I have been experiencing a lot of dots throughout my printed pages after changing out some new / Amazon replacement toner cartridges. No they are not brand new but refurbished toner cartridges and New drum. After that it did not correct problem.

I ran the internal cleaning spec from the manual buttons on the machine. to my surprise the first page was nasty black. I cleaned it several times just to be sure.

Again I got black and blue toner dots on the leading edge on top of page and on left side of page and blue dots about every one inch on the right side.

Spoke to HP India Support who did diagnostic and they said it must be a hardware issue.

To my surprise when I open up the top and took out all toners and Drum there was a tone of toner throughout the bottom. I took a strong vacuum and vacuumed and then blew out anything i couldnt see. I proceded to then use cue tip, cotton balls with 90\% alchol to gently clean any residue. I even took off the back panel and did those wheels.

Bottom line all other dots are gone, except the one Blue dot every inch on the right side all the way through the page.

What can I do before I trash this Thing!
by unknown on Oct 28, 2011 at 9:39pm Add comment
If only in one color it has to be the toner cartridge. You probably have a little bit of dirt or bump on the cyan roller that applies the toner. Best method is to remove the cyan toner and clean off all the cyan toner down to the black roller and then turn the roller and do it again and again. Put back in the printer and hopefully the mark will be gone.
by dmzcompute on Oct 29, 2011 at 2:13pm Add comment
Moe, you said,

"If you look at the right side, it will be off a bit. To realign it, grab the black carousel gear with your fingers and pull towards you while holding the left side stationery. Then move it in the direction it needs to go until it's close to alignment and let go and then push it outwards until it seats in place."

My two large black gears (left and right side) seem to be connected to the metal bar directly and don't move independently. What am I missing?

Also, I'm going for a match on both sides, right? The alignment marks on the black gear to the nubs on the smaller white ones?

by debsaok on Oct 31, 2011 at 11:15am Add comment
By pulling the gear inwards you disengage it and it allows it to rotate independently of the gear on the left. When you get done, you can eyeball the right and left slots for the toner cartridge and they should be exactly parallel with each other.
by moe on Oct 31, 2011 at 2:01pm Add comment
The color has faded on the left side (about 1") of my printer. The text is fine, but anything in color (pictures,etc.) is faded and the rest of the page is fine. Any suggestions anyone?
by unknown on Nov 28, 2011 at 10:57am Add comment
My 2840 is not cleaning the drum by the looks of things. its printing fine with black and white images but when i print colour the image is reprinted on the page over and over while getting lighter. The problem only started after replacing the drum. I have replaced the drum with a new one with it doing the same problem
by dnxwelkom on Apr 20, 2012 at 4:40am Add comment
By new, do you mean new OEM or new remanufactured? - moe
Getting a wide (2") vertical band on right side of the page, also several narrow ones on middle / left. Researching root cause... Can this be anything other than an imaging drum problem? Is there a way I can inspect (or better, clean) the drum?

Printer is used; was told imaging drum was replaced recently. Supplies Status indicated it was replaced Aug 19, 2011 and ran 1700 pages. Other cartridges have ink and appear to be genuine HP units (at least, they don't show empty... my exp. with remans is they show empty.)

The inside of this printer is full of loose toner, but from the video I pulled up on YouTube on cartridge alignment, seems to be common.
by noiseguy on Apr 24, 2012 at 7:12pm Add comment
You know... I look inside this printer and can see bands of blue/black toner stuck to the green roller of the imaging drum (the roller that clearly states "do not touch". The bands roughly correspond to where I'm getting the wide gray vertical bands on these prints.

Is there a way to clean this stuff off without trashing the imaging drum? Or is this just indicative of other issues and I need to replace the drum (or some other part of this printer?)
by noiseguy on Apr 24, 2012 at 7:45pm Add comment
You need to replace the drum. The wiper blade is bad.
by dmzcompute on Apr 24, 2012 at 8:39pm Add comment
OK, thanks for the input.

Read more elsewhere, wiped down the drum with alcohol and lint-free rag; figure if it needs replaced anyway it hardly matters what I do to it.

Streaks went away, print quality isn't great (it's light) but an improvement. After printing a couple test pages, now the entire imaging drum is now coated with toner. I assume that the wiper's suppose to be removing this toner as it rotates.

Do these imagining drums hold toner... act as a waste repository for toner? B/c this one seems to be full... just rotating the green drum while cleaning it was re-depositing toner back on it. I had to rotate it over a couple of times to get most off.

At any rate I appear to have at least isolated the issue to the one part. The wiper blade, I assume, is not a separately available part.
by noiseguy on Apr 24, 2012 at 9:16pm Add comment
Hi guys,
These posts seem to be in line with my problems. 2840, remanufactured drum and toner carts, getting a grey stripe all the way down the page. If I yank the drum and check, I can see a band of toner going all the way around the drum corresponding to the stripe on the page. I can rub it right off with a piece of paper. When I reinsert the drum and the printer does its initialization routine, more of the errant toner seems to come off and it's better for a while.

After reading up on this stuff, I came to the conclusion that the wiper blade or whatever equivalent it uses isn't getting everything. I guess it must be inside the drum unit since I can't see it anywhere. Do they just get bad with age or something, or is it more like there's some debris in there causing the issue?

I'm not really sure what it is about these drum units that supposedly runs out with age or what the remanufacturing people do to them to supposedly restore them to a more new-like working order. Obviously this is a get-what-you-pay-for proposition, but is this sort of thing generally an issue with remanufactured units?
by Ray Kremer on Jul 23, 2012 at 9:17am Add comment
Some remanufacturers do their due diligence and replace wiper blades, drums, etc. Some just add toner and package it back up.
by moe on Jul 23, 2012 at 9:21am Add comment
Indeed. Though on the 2840 the toner cartridges are separate from the drum unit.

I don't know if it's worth the effort to try to take this thing apart to see if I can fix the wiper blade. It works fine most of the time so I'm not really sure what goes on in there.
by Ray Kremer on Jul 24, 2012 at 4:47pm Add comment
I was speaking in generalities. That unit isn't easy to disassemble. The wiper blade would be located below the drum. You would have to take both sides off, unhook the drum shutter and remove the metal side plate holding the drum axle. The wiper blade is then visible. Held in by a couple of screws.
by moe on Jul 24, 2012 at 4:55pm Add comment
The cartridges are all installed but the printer will not work and on the L.C.D. states to install supplies. ( shows two not installed ) The alignment is off as the right side is about 3 teeth ahead of the left side . I found this when I replaced the black cartridge with a new one . The old cartridge was making a loud noise and the gear was very hard to turn. I think it need realignment. Please advise .
by richy D on Jul 24, 2012 at 11:37pm Add comment
Well do a search on this site for alignment of the carousel. I am sure this is your issue as the contacts are not working if you are 3 teeth off.
by dmzcompute on Jul 25, 2012 at 5:31am Add comment
Like I was saying about remanufacturers, there's good ones and bad ones. Common problem with the 2840 reman cartridges is they seize up. This causes the large carousel gear on the right side to jump out of alignment. I've posted the procedure to realign a few times. Like dmz suggested, do a search on the site.
by moe on Jul 25, 2012 at 9:40am Add comment
Thank you so much for your direction . With the information on this site and a video on youtube it was repaired . You should pad yourself on the back and feel good about helping others with there printer problems. This would have been a large expense to replace and the timing was not good . Thank you again so much. - richy D

Finally solved the problem of the gray - black vertical stripes. As it was suggested I disassembled the imager unit. It is not difficult: remove the screws on both sides of the unit and remove the plastic covers. Pay attention to the plastic tabs as well, you need to press the tabs in order to remove the side covers. Remove the moving lid from the unit. Facing the drum to you remove the upper front section plastic cover. Remove the screw from the upper back part and remove the plastic cover as well. Remove the two metal plates on the sides after remove the screws. Please note there is a white round plastic part coming off from an axle removing the left metal plate. Do not forget to put it back at the time of reassembly. The imaging drum can be removed if you bend the side plastic wall a bit. Reaching this state you can see the blades quite dirty. Remove the screws of the blades, remove the blades and clean both of them. Clean the skeloton unit. Be carefull: do no turn upside down the skeloton. On the right side there is a rectangular hole leading to the waste tank area. Turning upside down you will have a quite a mess of fallout of dust. Clean the imaging drum carefully with soft tissue paper and isopropil alcohol. Wear thin rubber gloves and wash your gloved hands frequently in order to avoid further dust contamination. Work slowly and patiently. Remember every diassemble step in order to be able to reassemble. After installing the cleaned unit I got the demo print as a white with some yellow part. I was not suprised because I thought I have a misaligned carousel. I have checked the marks on the two sides and found the carousel alignment right. I placed back the cartridges paying attention to rotate the carousel to the right position. Every cartridge should go into its slot effortesly. Tried printing again. At that time the printing was OK. I think what helped is to release the break of the carousel by a stick, removing and placing again the cartridges and removing the stick to operate the break on. I think the carousel can be misaligned two ways: first at the left and right gears, second the carousel's cartridge feedig position relative to the standing cartridge feeding position. These two should be in line precisely to be able to acceprt the cartridge without any friction. It was a good experiment. Good luck!!

by Mita on Feb 9, 2021 at 11:56am Add comment