Suggestions JV33 - Magenta starvation but comes back after hard clean

[eesanopi]

So I tried the steps you shown me. I pulled ink from both lines gently and ink were drawn out on both (vacuum on both lines). It wasn't just air like how it was shown on your video.

I am not too sure if I performed it correctly but the problem is still there. Just a reminder that the cap top is just about brand new.

Maybe the print head is faulty? It is several years old.

Sorry to hear that but I think is not the printhead, if the cap top is sealing good then you could have air bubbles in the line, it can be formed because a loose nut in the line, a damaged oring inside nuts, etc. When you do a hard clean vacuum pump removes the air bubbles, but they form again because the leak.

You need to do a full inspection in the ink line, from the cartridge valves up to the dampers, to do this remove the back guard under the cartridge station and review hose connections to the valves, pull the hose firm to check if it is loose (take care because if hose outs from the valve you can have an ink spill), do the same for both cartridge valves, check if the nut is tight to the valve (caution, excess or torque can damage valve connection), check fittings between both ink lines in same way, review the fittings to the upper damper connectors, When you need to do a hard clean check during the ink pumping if you reach to see any bubble in the ink line, for this do you need to remove the printhead cover, you need to be patient and observant in every detail. Maybe i could send you some pictures from this parts next sunday.

Regards

Edgar

 

[odshawaii]

Sorry to hear that but I think is not the printhead, if the cap top is sealing good then you could have air bubbles in the line, it can be formed because a loose nut in the line, a damaged oring inside nuts, etc. When you do a hard clean vacuum pump removes the air bubbles, but they form again because the leak.

You need to do a full inspection in the ink line, from the cartridge valves up to the dampers, to do this remove the back guard under the cartridge station and review hose connections to the valves, pull the hose firm to check if it is loose (take care because if hose outs from the valve you can have an ink spill), do the same for both cartridge valves, check if the nut is tight to the valve (caution, excess or torque can damage valve connection), check fittings between both ink lines in same way, review the fittings to the upper damper connectors, When you need to do a hard clean check during the ink pumping if you reach to see any bubble in the ink line, for this do you need to remove the printhead cover, you need to be patient and observant in every detail. Maybe i could send you some pictures from this parts next sunday.

Regards

Edgar

Thank you for the tips Edgar. Any pictures you can send would be of great help.

Here in Hawaii, we don't have Mimaki technician so these technical troubleshoots can be a bit hairy for me.

 

[eesanopi]

Hi, I didn't have time to take pictures las weekend, but I did some trims from PDFs, I hope it will be useful for you

Remove the cover in a red circle showed in picture 1, you'll see the ink lines attached to the cartridge valves through brass nuts (in picture 2 red arrow is pointing the valve and yellow arrow is pointing ink line), under this joint you'll find a coupler similar to picture 3, you need to review and retighten all this nuts, take care with the torque to the the cartridge valve, to much torque can damage the valve ouput because is plastic (picture 4), sometimes if is to old this part could be cracked and let air enter to the system. Nuts have a oring inside, check if it is in good condition (picture 5).

Regards

Edgar

 

[odshawaii]

Hi, I didn't have time to take pictures las weekend, but I did some trims from PDFs, I hope it will be useful for you

Remove the cover in a red circle showed in picture 1, you'll see the ink lines attached to the cartridge valves through brass nuts (in picture 2 red arrow is pointing the valve and yellow arrow is pointing ink line), under this joint you'll find a coupler similar to picture 3, you need to review and retighten all this nuts, take care with the torque to the the cartridge valve, to much torque can damage the valve ouput because is plastic (picture 4), sometimes if is to old this part could be cracked and let air enter to the system. Nuts have a oring inside, check if it is in good condition (picture 5).

Regards

Edgar

Aloha Edgar,

See attached pics:


I opened the cover in the back to inspect the valves and ink lines. The lines are filled with ink and the brass nuts seem to be torqued securely to the lines.

I did not attempt to undo any parts as I didn't want to risk making my problems any worse.

Overall, it appears to look like it's in good condition but please advise.

Thanks, Joe

 

[eesanopi]

Aloha Edgar,

See attached pics:
View attachment 137026 View attachment 137027

I opened the cover in the back to inspect the valves and ink lines. The lines are filled with ink and the brass nuts seem to be torqued securely to the lines.

I did not attempt to undo any parts as I didn't want to risk making my problems any worse.

Overall, it appears to look like it's in good condition but please advise.

Thanks, Joe

Hi Joe.

As yo say, in this pictures all looks very good, so I can't help you with additional tips, my only advice is you need to be very observant to try to detect the failure when it is present, sorry.

Edgar