LaserJet 4 Plus grinding noise -- but it's not a LaserJet 4 Plus????

There is definitely a gear issue with my LJ 4 Plus -- at least the top
cover and part number in the back *claim* to be a LaserJet 4 Plus. The
gear issue has something to do with the fuser or related gear mechanism
because there is a grinding whenever the rollers move. The paper also
stops at the fuser, resulting in a printer jam.

So, I replaced the one gear (comes with it's own metal arm) that
attaches to the main motor mechanism and is supposed to move the fuser
mechanicsm. That was not the problem, however. The larger, thinner
gear (of the e three that are on the side of the fuser) snapped in two.
So, I then ordered a replacement for that.

When I got the replacement, however, it was the wrong gear. The gear
that broke has 34 teeth. The one that I was sent (which I confirmed
through HP's service manual *is* for the 4 Plus) has 42 teeth. The
printer replair place (web-based) didn't believe me until I sent them a
photo of the fuser gear mechanism. They confirmed that the fuser is for
a LaserJet 4, *not* 4 plus.

They also claim that it's *impossible* to fit the fuser for a 4 into the
chassis for a 4 Plus, but this toner cartridge is most definitely for a
LaserJet 4.

So, I still am getting gear issues *and* it appears that some way, some
how, I have a LaserJet 4 fuser in a LaserJet 4 Plus which is supposed to
be impossible. I'm afraid to buy a 4 Plus fuser because a 4 and 4 Plus
fuser are not supposed to be able to fit into the same chassis.

Has anyone run into anything resembling this while in a non-intoxicated
state? I am completely stumped and the printer repair place that I
was dealing with is completely stumped by this as well.

John:

I agree with your Repair place. The LJ 4 Plus and the LJ 4 have different
Fuser and you can't swap Fuser. Here are the part numbers for each Fuser:

LJ 4 Plus: RG5-0879
LJ 4: RG5-0454

One of the quick way to tell a LJ 4 Plus and LJ 4 is to check the Menu. LJ 4
Plus has Power Save Mode setting. LJ 4 doesn't.

Dewaine
John Berger wrote:

There is definitely a gear issue with my LJ 4 Plus -- at least the top
cover and part number in the back *claim* to be a LaserJet 4 Plus. The
gear issue has something to do with the fuser or related gear mechanism
because there is a grinding whenever the rollers move. The paper also
stops at the fuser, resulting in a printer jam.

So, I replaced the one gear (comes with it's own metal arm) that
attaches to the main motor mechanism and is supposed to move the fuser
mechanicsm. That was not the problem, however. The larger, thinner
gear (of the e three that are on the side of the fuser) snapped in two.
So, I then ordered a replacement for that.

When I got the replacement, however, it was the wrong gear. The gear
that broke has 34 teeth. The one that I was sent (which I confirmed
through HP's service manual *is* for the 4 Plus) has 42 teeth. The
printer replair place (web-based) didn't believe me until I sent them a
photo of the fuser gear mechanism. They confirmed that the fuser is for
a LaserJet 4, *not* 4 plus.

They also claim that it's *impossible* to fit the fuser for a 4 into the
chassis for a 4 Plus, but this toner cartridge is most definitely for a
LaserJet 4.

So, I still am getting gear issues *and* it appears that some way, some
how, I have a LaserJet 4 fuser in a LaserJet 4 Plus which is supposed to
be impossible. I'm afraid to buy a 4 Plus fuser because a 4 and 4 Plus
fuser are not supposed to be able to fit into the same chassis.

Has anyone run into anything resembling this while in a non-intoxicated
state? I am completely stumped and the printer repair place that I
was dealing with is completely stumped by this as well.

John Berger wrote:
There is definitely a gear issue with my LJ 4 Plus -- at least the top
cover and part number in the back *claim* to be a LaserJet 4 Plus. The
gear issue has something to do with the fuser or related gear mechanism
because there is a grinding whenever the rollers move. The paper also
stops at the fuser, resulting in a printer jam.




Have you had this for a long time and it has been printing well?

Till now.

Or did you just buy this and it hasn't worked at all?

The remark about the menu being different for the HP4 and HP4Plus is useful.

There is a difference in the printer engines between the PH4 and the
PLUS model, and the cartridges would be incompatible.

On Sat, 12 Feb 2005 15:27:38 UTC, jbuch
wrote:

There is a difference in the printer engines between the PH4 and the
PLUS model, and the cartridges would be incompatible.

The print engines ARE different, as you say....but they use the SAME
toner cartridge (the 98A or 98X).

--
Bob Eager
begin a new life...dump Windows!

That was it! This is *actually* a LaserJet 4, *not* a 4 Plus! THere
is no power saver menu.

This printer was a "trash interception" from work. They were going to
throw it out because it's old technology and because it was clearly
broken. Looks like somewhere the top cover and part number piece on the
back were switched to represent a LaserJet 4 Plus. Intentions of why
that happened not withstanding, I'm just glad to know that's going on.

Mt wife, who worked with a regional, government IT shop, said that what
must have happened is that the toner cartridge went bad and the forces
of that broke the gears on the fuser. There was toner on the
electrostatic drum, which she said (as per the HP and IBM service
representatives that she had to deal with regularly) is a sure sign that
the toner cartridge is bad.

So, this damned thing is actually a 4, and I have to get a new toner
cartridge. Oh, well. It's still better than my old LaserJet IIIp
(which needs a cartridge as well) *and* it's was still cheaper than
buying an LJ4 on eBay.

Thanks for everyone's help in getting the mystery solved!

Dewaine Chan wrote:
John:

I agree with your Repair place. The LJ 4 Plus and the LJ 4 have different
Fuser and you can't swap Fuser. Here are the part numbers for each Fuser:

LJ 4 Plus: RG5-0879
LJ 4: RG5-0454

One of the quick way to tell a LJ 4 Plus and LJ 4 is to check the Menu. LJ 4
Plus has Power Save Mode setting. LJ 4 doesn't.

Dewaine
John Berger wrote:


There is definitely a gear issue with my LJ 4 Plus -- at least the top
cover and part number in the back *claim* to be a LaserJet 4 Plus. The
gear issue has something to do with the fuser or related gear mechanism
because there is a grinding whenever the rollers move. The paper also
stops at the fuser, resulting in a printer jam.

So, I replaced the one gear (comes with it's own metal arm) that
attaches to the main motor mechanism and is supposed to move the fuser
mechanicsm. That was not the problem, however. The larger, thinner
gear (of the e three that are on the side of the fuser) snapped in two.
So, I then ordered a replacement for that.

When I got the replacement, however, it was the wrong gear. The gear
that broke has 34 teeth. The one that I was sent (which I confirmed
through HP's service manual *is* for the 4 Plus) has 42 teeth. The
printer replair place (web-based) didn't believe me until I sent them a
photo of the fuser gear mechanism. They confirmed that the fuser is for
a LaserJet 4, *not* 4 plus.

They also claim that it's *impossible* to fit the fuser for a 4 into the
chassis for a 4 Plus, but this toner cartridge is most definitely for a
LaserJet 4.

So, I still am getting gear issues *and* it appears that some way, some
how, I have a LaserJet 4 fuser in a LaserJet 4 Plus which is supposed to
be impossible. I'm afraid to buy a 4 Plus fuser because a 4 and 4 Plus
fuser are not supposed to be able to fit into the same chassis.

Has anyone run into anything resembling this while in a non-intoxicated
state? I am completely stumped and the printer repair place that I
was dealing with is completely stumped by this as well.

The Toner cartridge is used on the following printers in addition to LJ 4
& LJ 4 Plus:

HP LJ 5
Apple LaserWriter 600/630
Apple LaserWriter 16/600 PS
And on eof the Canon Model that I forgot.

D.

Bob Eager wrote:

On Sat, 12 Feb 2005 15:27:38 UTC, jbuch
wrote:

There is a difference in the printer engines between the PH4 and the
PLUS model, and the cartridges would be incompatible.

The print engines ARE different, as you say....but they use the SAME
toner cartridge (the 98A or 98X).

--
Bob Eager
begin a new life...dump Windows!