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Jeff Liebermann Jeff Liebermann is offline
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Default HP LaserJet 4000 paper feed issues again.

On Sun, 12 Oct 2014 10:53:21 -0700, "David Farber"
wrote:

I removed the tray assembly 1 (that's the manual feed unit) and looked for
any irregularities.


I was referring to Tray 2. Unscrew the well hidden screws holding the
Tray 2 assembly to the printer, and the tray and the tray mechanism
should fall off. Take it apart and I think you'll find yet another
solenoid. I'm not sure and have no easy way to check right now.

So I put it back together and for now, it's working
again.


I hate it when that happens. It should fail again just when you need
the printer most.

It would seem to me that it couldn't be a roller problem if the
mechanism stalls out and giving the pickup roller a little push gets it
going again.


I beg to differ. The timing of the paper feed is controlled by the
solenoid you fixed. Mangle the timing in any manner, and it will act
something like what you've described.

The page count is over 40,000 now. I wonder how many new
printers last that long.


On the 4000/4050/4100 series, I have so replace the rubber parts, some
gears, and rebuild the fuser at about 50,000 pages. Much depends on
the environment. In a really clean office, I can sometimes go to
about 75,000 before anything needs replacing. At a local auto shop,
I'm lucky if anything prints 10,000 pages before something goes awry.
The worst was a machine shop, where everything was coated with a
mixture of metallic dust and lubricant, which operates like an
abrasive. I have 4200/4250/4300/4350 printers in tax preparation
offices that show well over 150,000 pages. The trick here is that I
do a pre-emptive cleaning and roller replacement every year before tax
season. That's about $25 in parts, $75 in labor per printer. After I
started doing that, I've had no after midnight phone calls from the
tax customers demanding I run over and fix their overloaded printer.
The most I've seen on a printer was a LJ4+ with over 250,000 pages. It
didn't die from overuse, but rather fell apart when someone dropped it
during an office reorganization.



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