GR3750 Inking Roller Problem. Thanks in advance!!

[c.chris]

Hello;

I have a drum locked inside the unit previously and I follow some posts here to unlock the drum from the unit. Since the drum roller inside is not in the "home" location, so I open the back cover of the unit and pull the belt until it comes back to "home" position. Now I can insert back the drum.

However, when I pull the belt, I also unlock a hock at the back of the unit that control the "inking roller" -- I don't know the terms but "inking roller" means the plastic roller that sit right below the drum that press the paper to the drum in order to let the drum press the content on the paper.

So, now the "inking roller" will not come up and press the paper to the drum. Paper will not pass through the unit anymore and now I am stuck.

Any idea to get this problem fix? Thank you very much!!

Chris

[CableGuy]

Pressure roller

Hi that part you are refering to is called the 'Pressure Roller'. One of a few things could be causing your problem....

1. The alignment sensors could be dirty causing the machine not to see the paper in that area and therefore the pressure roller will not engauge. You'll need to clean both sensors there.
2. The cable from the pressure solonoid may be broken, i.e. the wires are broken inside the plastic covers
3. The pressure setting could be out and would need reseting to their correct positions.
4. The pressure hook and/or lever may be worn out and would therefore need replacing and the settings done.
5. Your timing could be out, which needs to reset into the correct position.

Hope this helps

[c.chris]

Thanks for your reply CableGuy. Now I know it calls "The pressure hook and/or lever".

I un-hook the pressure hook when I pull the belt to make the rotary back to home position. The pressure hook should always hookup or not? I found it is hard to hook it back now.

Chris

[CableGuy]

Pressure hook

Hi
When the drum is in 'home' position the pressure hook should NOT be engauged. This only engauges when the paper is under the drum.

[c.chris]

Hi CableGuy,

It is now un-hooked and I monitor the pressure hook action during printing (actually it wouldn't print since the pressure roller will not grab the paper to press through the drum right now). I found the timing for the hook action is wrong. It supposes move a bit to hook up the lever when it goes up. However, now it move a bit when it is down. So it cannot hook up the lever.

Is there any way to reset that hook action timing?

Thanks.


Chris

[CableGuy]

Hi

Sounds to me as if the drum timing belt may be out and that may be causing the hook to release too early. But not standing infront the machine myself, I couldn't say for sure. If you are not used to working on these I would recommend that you get an engineer to set it up for you, because it is very easy to turn the machine into a boat anchor if you go fiddle about with settings that shouldn't be adjusted.

[c.chris]

I wish the attached picture will make it easier to troubleshoot the problem.

IMG_0208.jpg

I monitor the movement of the hook when test print a page. It move up and it SHOULD move a bit to hook up the lever but now it doesn't move when it is up. Instead, it move a bit (hooking action) when it is down. I think it is a timing issue on the hook to perform the hooking action after I unhook it manually.

If there is any dip switch or reset key combination, I would like to give it a try.

Thanks, CableGuy.

Chris

[CableGuy]

Looking at the picture, it seems that the parts are not worn. As far as the settings go, they are mechanical adjustment, not done using dip switches. As I said earlier, it is best done by a qualified engineer as it is possible to cause more damage by adjusting the wrong things.
Good luck

[c.chris]

Hmmm... business is bad and I really want to save $140 Canadian about this. Any chance you can post me the related information and I will take me chance on that.

Thank you very much CableGuy.

Chris

[c.chris]

Any "guru" can give me some hints? I think it just about resetting the pressure hook timing.

Thank you.

Chris

[joelsa12]

Too many answers not enough info!

There are many things that can cause the pressure roller not to engauge. Please send photo of the two round discs that are located in the back middle of machine. By looking at these I will be able to tell if the machine needs to be timed or if it is a part. Thanks.

[c.chris]

Great!

Here is the picture of the back:

IMG_0202_1.jpg

As a reminder, originally the drum stuck inside and I follow some guides here to take the drum out. Then I pull the rotary to "home" position. At that time, I unhook the pressure hook. Then the "problem" happen.

Thank you very much.

Chris

[joelsa12]

Out of time

You need to loosen the drive belt.(done at the paper feed clutch) And the disc on the right while sitting at the back of the machine needs to have the small timing mark on the disk right under the sensor that reads it. The disc on the left should have the dot right in the middle of the sensor just like it is. Looks like something was impeading the drum while the main motor was still driving. Good luck.

[joelsa12]

Did you fix it?

I save you money and no feed back????? You need help and once you get it you are gone. A simple thanks is good enough. Next time I will not be so fast to diagnose your ills.

[c.chris]

Oopps... I am not gone yet. I am still try my very best to follow what you said... I am just too focus on that and I would like to get some progress before I give you reply.

Sure you have my heartily thanks. THANKS and I will post the result later as well.