Vintage printing: help identifying an HP Laserjet 4000 part

Hi everyone,

I have got a question about the good old printer HP Laserjet 4000.

Does anyone know the name of the big black part (internal component) that integrates nearly all the assemblies (Fusing, Delivery, Printer Drive, Paper Feed Guide, Tray 1 Pickup, Tray 1 for instance)?

Its reference is RB1-8665 and its shape is on the drawing enclosed.

Thanks for helping me!

In engineering speak, this would be referred to as the chassis. Not sure where you found the reference code but that essentially is the name. It's likely you wont find this part available from a part supplier as its not a consumable or service part, but you might find it on ebay or something sold by somebody who parted one out.

I do consultation work in the mechanical and electro-mechanical space. I may be able to help you if you would like to share with me the problem you are trying to solve. I can help advise on repair options, repair limitations, and more.

Hi MrBird,

Thanks for your answer!

Though it might seem unbelievable I have not found any online listing for the RB1-8665 yet.

I have many spare parts from my HP Laserjet 4000 N and I am trying to figure out what they are.

Yes, it's the main chassis, as @MrBird has mentioned.

The LJ4000 is still an excellent printer if in good condition, but it's an old workhorse today.
They were often found in corporate-office settings, as they were priced above the reach
of most consumers at the time. I owned one years ago because I found it headed to
a client's trash heap. I was able to salvage it because I serviced those printers(mechanically)
at the time of acquisition. I could still even rebuild the fuser assembly if I had the parts
(and there are a LOT of parts to a proper rebuild!).
Mine needed only a paper-sensor, pickup roller, and fuser cleaning.

As mentioned, this is very unlikely to be made available as a part on its own.
If you're really determined to get one, you'll do better to seek a same-model printer
being sold for parts/repair, but it's a heavy beast, so you'll have to pay for shipping.
Acquire the printer, then you'll have a nearly full set of parts to try against the other.

While the N-model is not the same in all its electronics, there are many parts which
can be used interchangeably. However, there are some mechanical differences.
Unfortunately, I don't recall what they are other than a couple of paper sensors
or display assemblies or pickup rollers, or similar.
In short, the LJ4000 does not equal the LJ4000-N, or vise-versa.