HP LaserJet 4300 - Wrinkling Paper

That is a real good idea.  I'll get some and try it if we wrinkle any more.

I accidentally noticed some small indentions on the edge of the ream of paper in Tray 4.  When I took several examples of the wrinkled paper, the wrinkles matched with the indentions on the edge.  The indentions look like they were left by some sort of paper moving arm at the time of manufacturing.

We opened a new ream of paper, same marks.

We opened a third ream, different paper company, and there were no indentions.  I have put that third batch of paper in the printer.  We will see if the problem goes away.

check if the paper runs straight; i mean nice against the sides without skewing

How would one do that.

I would love to removed the covers and watch the paper move through the printer as it is printing, but I have never figured out how to get an HP to print with covers removed.  There are simply too many little sensors that notice when something is missing.

As an update, The paper was not the problem.  The new paper wrinkled in the same location.  I did, manually, stage - by - stage, push, pull and otherwise force a piece of paper through the entire paper path.  I could not find anywhere that it was getting caught.  Also, upon closer inspection, I noticed that the printed letters in the wrinkles were NOT malformed.  This made me reassess and realize that the paper must be flat before the fuser, otherwise I would expect malformed characters.

I also noticed that the wrinkles still seemed to be very well pressed, like they had been ironed (fuser).  In all of this examination, I have removed and inspected the fuser and the path leading into, and out of it.  Since that inspection, at last check, no more wrinkled paper.  Is it possible that the fuser was some how misalligned?

That sounds like a really good possibility, but I know that I've never seen that before as an issue and I've used a ton of HP printers in that 4xxx range.

Same here.

Never seen vertical wrinkles (except in the case of bad paper) before.  I like the hp4000 series.  They are fast, reliable workhorses.  The one bit of information that makes me beleive this may be the problem is the fuser removal process.  Correct me if I am wrong, but I seem to remember most, if not all, other hp 4000 series printers utilize capture screws to hold the fuser in place.  This 4300 simply had the two "push buttons" on the bottom of the fuser that allow you to pull it out.  Maybe that allows some slack, or wiggle room in the positioning of the fuser?

Can't answer that right off.  I don't think that I've ever had to remove a fuser.  We do almost no maintenance on the printers because we have so many. We contract with a service to do maintenance on the printers and as I said, I've never ever seen this particular problem.

you open it during the print and see the paper in the print station, or after it..

Thanks for the comments.  

There is a new development.  It is now wrinkling paper from all trays.  This includes standard 20lb paper as well as 28lb bond paper.  It does seek to be caused somewhere in the upper part of the printer.  

I am looking real closely at the fuser as the culprit, but it only has 35,000 pages on this one.  A good HP service tech is going to look at it today and let me know what he thinks.  His initial pmpression is that the fuser is bad.

Anyone have a fuser cause this problem, or is he just taking the easy way out recommending the fuser be replaced?

We are ordering a fuser today.

I'll update this post if it corrects the problem.