unknown

asked Aug 24, 2003 at 10:09am
Hp HP LaserJet 4M

HP Laserjet 4m Paper Jam

Im trying to fix a paper jam issue on a vintage HP Laserjet 4m

Heres the problem:

The paper jams about 1 cm into the lower exit roller. This recurs at exactly the same place each time. There is no accordian style crinkling of the paper. The jam occurs when using either the cassette tray or manual feed. Ive tried different papers to no avail. The print quality appears to be good.

Things Ive tried so far (after browsing through some of the posts in this forum) :

The paper pickup rollers seem fine.

I removed the fuser assembly and checked the gears which appeared normal. The gears on the motor assembly also appear fine. I dont hear any clicking noises when the motor runs.

The exit sensor arm moves freely although it does seem to wobble a bit. Im not sure if this is normal. I blew some compressed air over the sensor just to be sure.

I also removed the exit assembly and cleaned the rollers with isopropyl alcohol. The rollers have been changed once before using the accordian jam kit from this site. They appear to move freely, so Im guessing that the trouble lies elsewhere but I could be wrong.

The problem still persists. Any suggestions?
Are the exit rollers newish?
Ian
by unknown on Aug 24, 2003 at 11:08am Add comment
Ian, the rollers appear newish. They were probably replaced a few months ago but Im not sure. On closer inspection of the exit sensor, a nub on which the paper-end of the arm pivots appears to have broken. I have opened up the fuser assembly (the nub is part of the plastic casing with the 'Caution Hot surface' sticker. I think I'll glue on a small piece of plastic and see if it fixes the problem. Ill post my findings once Im done. Is it possible to replace just the plastic casing?
by unknown on Aug 24, 2003 at 11:57am Add comment
Dear Rajiv
Although Im by no means an expert, it would seem that your problem is in the fuser rather than the exit roller. I say this because of the fact that there is no accordian effect. ie the paper stops being pushed by the fuser before the roller stops pulling it, therefore no accordian.
I hope your makeshift attempt to repair works. I dont know about the availability of casing only. Might not it be better to try and obtain a replacement fuser if necessary perhaps a second hand one or a reconditioned one. Presumably you are in the USA. Perhaps you might email Moe on this website to see if he can supply one.
I cant help since I am in the uk.
Hope this helps
Ian
by unknown on Aug 24, 2003 at 1:17pm Add comment
Surprizing the paper got that far. If you need one of those fuser exit guide plates, we have them in stock.
by moe on Aug 24, 2003 at 1:59pm Add comment
The sensor arm was the problem and my hack seems to be working quite well. I fashioned a plastic pivot and fixed in place using some superglue. I just printed a 100 page document without a single jam. This certainly is a nice printer.
by unknown on Aug 24, 2003 at 3:43pm Add comment