loud thumping and gear grinding noise

[Mattuk]

Did you ever change the pump. I have two printers in bits at the moment. One for spares and one that works apart from the grinding noise. I can see how the small cog underneath is raised to engage the Pump cog and also lowered. Whilst this is free to move up and down I can't make out which bit is the problem.  When the grinding starts the pump does infact turn.   So what did you find in the end?

[LuSiD]

I am sorry but I didn't have the time (or the patience) to deal with this printer. I went and bought a Canon Pixma instead. No more HP printers (or laptops) for me.

[Mattuk]

After taking apart another 5520 I can now see what the problem is.  It is not the pump. It is the print head which fails to move back from the entreme right edge once the small trigger catch is engages a cog to bring the cleaning tray forward.

As the the cleaning tray is moving forward, the pump roller ( which is now being driven ) is still turning towards you looking from the front of the printer.

When the cleaning tray get to the final postion, the small triger latch is still engaged and as the tray has reached its final position the print head now needs to move to the left about 5mm ish to disengage the small trigger lever that locked the cog to drive the cleaning tray

If you just slight push the print head about 5 mm to the left at that stage the noise stops and the gears continue to turn the pump.  I have not yet decided why the print head does not do the final move....

[polymer]

this printer was never quality enough or priced high enough to take it apart. HP feels the same way too.
I have a different HP printer now that is worse... eats paper... but again, the cost is low enough for HP to not care about that.

I'm curious how LuSiD likes the Canon... the Canons I've had in the past were ink hogs. I'm printing a lot if text (black /white) and don't want a printer eating up the color for that.

[egrB]

Mattuk, I have the same observations - the problem is in the cleaning tray. 

Instead of moving/pushing the print head you can pull the power cable out and try to free it up by spinning the sprocket on the left side of the printer back and forth manually. 

So here's what I got so far. I'm going to check what makes it jam. Is it because of some mechanical problem or software glitch, which makes this tray moving while it should not. 

[Mattuk]

I have the 5520 printer with the probelm and also a 5510 that I have in bits to try and find the problem.

From what I can see is...  Towards the right hand side of the printer there is a small toggle lever that operates when the printer head pushes against is as it travels to the far right hand side. When this happens this toggle lever raises a small cog which then enables the gears to move the cleaning tray forward.

The problem is that when the cleaning tray gets in it final position the Print head asembly is still holding the toggle switch to the right and therefore as the tray cannont move any more the cog which is still engaged starts to jump as it is still being forced to turn.

It seems that if the print head needs to moves back to the left a few mm to release the toggle switch witch will release the drive to the tray cog and then the same drive unit which moved the tray can continue to turn and drive the pump without any noise... 

I am driving the system with the large cog on the left so I can see exactly what it does......

I cannot figure out why the print head does not allow this toggle swtich to release.  The head has free travel..  I have tried all the possible solutions and even removed the backup battery to see if the Firemware was corrupt.

Regards   John

[Mattuk]

To add a bit more clarity. This is an upside down view of the cogsso you can see how it work.....

The small toggle lever in the previous picture is linked to the pulley shaped wheel ("A")  and when the print head assembly moves to the right hand side is pushes that pulley shape ("A") complete with a cog ("B") to engage with ( with this cog "(C) ). 

That then starts the cleaning tray to be driven forward.

As the cleaning tray gets almost to it final position the other white cog ("D") is lifted by a plastic peg on the under side of the cleaning try and engages with ("E") and ("F").

This then engages the pump...  The problem is that the pump cannot turn because cog ("B") is still latched to cog ("C") and as the cleaning tray is already in it final position cog ("B") and ("C") are fighting to turn but can't as it is also still engaged into the rack teeth on the cleaning tray which can't move any more forward..

If the print head move slightly back after the cleaning tray was in it final position the toggle switch wount dis-engage and the pump could turn.....  Hope this make a bit of sense....

[egrB]

John, thank you, that's a really great update. My thought now is that it's not a mechanical problem.

Turn the printer off and move the carriage to the center. Then just immitate the carriage parking position manually by pushing the toggle lever to the right. While pushing it spin the axle to move the cleaning tray to get it fully moved out.

There is no way to avoid grinding noise without stopping the engine in this position, but it continues spinning. If you leave the lever the tray just go off back, which is not the right position for parking carriage.

What do you think?

Best regards,

Egor 

[Mattuk]

Hi

"Turn the printer off and move the carriage to the center. Then just immitate the carriage parking position manually by pushing the toggle lever to the right. While pushing it spin the axle to move the cleaning tray to get it fully moved out"

I have done all that many time to see how it works,,

There is no way to avoid grinding noise without stopping the engine in this position.

This is true..  The question is...  what should be happening when the cleaning tray reaches its final position and cannot move any move forward?

If you leave the lever the tray just go off back

No,,,,  not really.... because the cleaning tray has moved forward,  and underneath the cleaning tray there is a plastic peg which lift up another gear to engage the pump. As long at the cleaning tray is in it final position, the pump cog is also engage. If you gengle push the print head away from the right hand side so that the toggle switch is dis-engaged, the noise stops and the pump continues to turn,,,,,

So there is a problem with the print head position.   The toggle switch is doing the correct job by driving the tray forward and as the tray get almost to its final position the underside lever raises the another cog to drive the pump. This mechanical movement cannot be changed.

Thats how it works, 

The part that is wrong is that the toggle switch does not get released by the print head movement so the motor is trying to drive the pump and also trying to move the tray which is at is limit,,, hence the tray cogs jump.......

I am wondering if it is a frimware problem. The transparent band with the makers is clean so the head knows where it should position itself...

I do no have a working printer to see if the print head does move back from the extreme right by about 5mm after the tray is in its final position to release the toggle switch and in it final position the underside lever is still engaged to drive the pump......  If it does that ( and I am sure if should ) then that is the problem....

[egrB]

I'm wondering does it make sense to move this transparent band slightly left.  

Here is the video with the same issue. https://www.youtube.com/watch?v=seVkzWWSScY

Seems that the head position is static during the tray movement.