itso

asked Apr 17, 2012 at 4:52am
Hp HP LaserJet 4

HP LJ 4+

We have this printer and has started not pushing paper out. I opened the back and press the lever so the Paper Jam error does not come on and when we send a print job the rollers, which are HOT are not turning.

Is this the Fuser, if so what is the proper name or part #?
Is it difficult to replace?
Is better just to buy a new printer?

Regards
IS there a good resource for buying the HP Jetdirect NICs for the HP LJ 4+?

We have another HP LJ 4+ that when the ink is laid to the paper it ALWAYS has streaks and just a lot of ink all over the paper.

I have tried another cartridge, no change.

Any ideas?
by itso on Apr 17, 2012 at 4:59am Add comment
We have some working used NICs. The printers use toner, not ink. What you describe is a toner cartridge problem. Take the cartridge out and pull the drum shutter open. You'll see the drum covered with toner. If you turn the gear with your right thumb, the drum should be cleaned by the wiper blade inside the cartridge. You want to turn it in a clockwise direction, away from your body. We do carry replacement wiper blades as well. - moe
In most cases, it's the coupler gear that drives the fuser that has worn out. It is also possible for the heat roller gear on the fuser to break. You would have to remove the fuser assy. and turn the gear manually to check it. You can also see the coupler gear inside the printer. It's probably turned yellow and is missing a tooth or two. We can supply you with either gear and videos for replacement.
by moe on Apr 17, 2012 at 9:40am Add comment
"You would have to remove the fuser assy. and turn the gear manually to check it." How do I do this?
by itso on Apr 17, 2012 at 5:12pm Add comment
there are only 2 screws, right in front of the fuser unit on the bottom metal plate, holding the fuser unit in. remove those 2 screws and the fuser unit pulls right out.
by seriously on Apr 17, 2012 at 6:27pm Add comment
Ok, we are talking about the back of the printer, where you open the door, correct? - itso
Correct.
by moe on Apr 17, 2012 at 11:12pm Add comment
I took this part out and have a picture of it, but see no where to upload, to make sure I get the right part.

If I turn the gear hard enough it moves, but not much. I see no teeth missing.
by itso on Apr 18, 2012 at 2:52pm Add comment
Here's a pic of it http://www.fixyourownprinter.com/reference/guides/fuser/ex
Did you look at the gear in the inside of the printer? Lower left as you're looking in the opening at the back where the fuser used to be.
by moe on Apr 18, 2012 at 4:51pm Add comment
Moe is correct. Try removing the fuser, visually check the gearing on the fuser and try to turn it. If all the fuser gears are ok and you are able to turn it its more than likely the fuser drive gear asm. You can inspec this by removing the toner, and manualy turn the gears at the right side of where the toner sits. Any worn or damaged gears and this would have to be replaced. Easy enough to do, only a few screws(3/4) and can be acessed by removing the board and cover at the RHS of the printer (as you face it from the front). With the screws removed release the asm from the rear of the printer with the fuser removed.
by unknown on Apr 19, 2012 at 5:02am Add comment
Ok, I have the printer and have pulled the toner cartridge out. There is a gear on the right, which I try to turn and can not. I am not sure if it takes much force to turn, but from what I have tried it is not moving.

I am guessing this is what drives the toner as well. With this in mind, if this was broke then the toner would not be distributed to the paper correct? This is not the problem.

Toner goes to the paper, the paper is just not passing through this fuser assembly, because it does not turn.

Job goes to printer, printer picks up paper, lays toner to paper, passes paper to fuser, JAM. Fuser not moving. - itso
John,

A bit more than 3 or 4 screws need to be removed. The formatter has to be removed along with the main motor. It is better to order the kit from this site as it gives full instructions.

http://www.fixyourownprinter.com/kits/hp/K21
by dmzcompute on Apr 19, 2012 at 5:36am Add comment
Sorry, 3/4 screws was ment for the drive gear asm, if i didnt make that clear ;). Not for the total repair
by unknown on Apr 19, 2012 at 5:40am Add comment
The gear won't turn because you're trying to drive the fuser as well. If you take out the fuser, then you'll be able to turn it and the coupler gear in question is at the back of the drive train. Easier to see it from the back.
by moe on Apr 19, 2012 at 2:27pm Add comment
The fuser is sitting on the table, there is nothing in it. No fuser nor toner.
by itso on Apr 19, 2012 at 3:05pm Add comment
We are referring to the white gear at the end of the black foam roller? I just tried it with a printer we have in the shop. Fuser out, the gear turns with a little effort and I was using my left thumb, which is my weaker one.
by moe on Apr 19, 2012 at 5:00pm Add comment
let's cut the frustration and just watch this video at youtube:

http://www.youtube.com/watch?v=qcnNkzi5BAg

part 2:

http://www.youtube.com/watch?v=KWRJnKlUxhw
by seriously on Apr 19, 2012 at 10:04pm Add comment
So, I need to replace the drive line gear? According to the guy in the video, this should turn pretty easy. The one in this printer will not move at all.

I don't understand how the toner got to the paper then, because the toner cartridge sits on this gear too.
- itso
So, I need to replace the drive line gear? According to the guy in the video, this should turn pretty easy. The one in this printer will not move at all.

I don't understand how the toner got to the paper then, because the toner cartridge sits on this gear too.
by itso on Apr 20, 2012 at 4:56am Add comment
"We have some working used NICs." Where are they and price?
by itso on May 2, 2012 at 10:42am Add comment