Air in lines Mutoh 628

[Racegrafix]

So I ran out of ink in two cartridges which introduced air into lines. I have tried using the little charge to fill lines but no change. Any advice on what to do? Nothing seems to change it.

 

[Solventinkjet]

It's probably a cap top or maintenance station issue. When a cartridge goes empty and doesn't flag the machine, no air should get in at all. If air did get in, one or more connection along the ink line is failing. The more likely case is the cap top or maintenance station aren't pulling ink properly and when the cartridges went empty, after you inserted new cartridges, the failing station couldn't pull ink back down into the head. I'd start with a cap top and flush the waste tubes to make sure they aren't clogged.

 

[Racegrafix]

It's probably a cap top or maintenance station issue. When a cartridge goes empty and doesn't flag the machine, no air should get in at all. If air did get in, one or more connection along the ink line is failing. The more likely case is the cap top or maintenance station aren't pulling ink properly and when the cartridges went empty, after you inserted new cartridges, the failing station couldn't pull ink back down into the head. I'd start with a cap top and flush the waste tubes to make sure they aren't clogged.

Im using refillable cartridges, so it seems like air would easily enter if empty ( i could be wrong).
The cap you are talking about, is that where the printhead normally sits? With the rubber seal? I have cleaned the rubber seal and no change.

How would I flush the waste tubes?

Thanks again for the reply, Im certainly no expert and need all the help I can get.

 

[Solventinkjet]

Im using refillable cartridges, so it seems like air would easily enter if empty ( i could be wrong).
The cap you are talking about, is that where the printhead normally sits? With the rubber seal? I have cleaned the rubber seal and no change.

How would I flush the waste tubes?

Thanks again for the reply, Im certainly no expert and need all the help I can get.

It depends on the bulk system you use but yes, if it's an open container, air could get sucked in that way. Once you put new ink in, it should be able to fill with a little charge. If it doesn't I would suspect the station or cap top as well. It should fill even with a couple of strong cleanings.

The cap top is the part the head sits on when not printing. If that hasn't been changed in about a year, I would definitely start there.

 

[Saturn]

What does the print look like? Or what issues are making you think it has air from cartridges?

I had a 628 for about 2 years and it ran trouble free except right before I sold it the pump off the maintenance station (between the captop and waste bottle) clogged up. Not only will you have missing nozzles, etc., but if you've been paying attention to the sound of things, you'll hear that it's not activating/sucking when it's supposed to. I had to manually pull a few cups of cleaning fluid through the pump to get it running again. Solventinkjet will sell you a syringe/plunger and tubes if you need them. Once I had the pump cleaned out it ran like a top again. Never permanently lost a nozzle or had any deflections. The guy I sold it to is still running it like crazy too.

I don't think the 628 includes a pump in their maintenance station, so you will want to clean it yourself if you can.


On a side not, the thing was a sipper on ink. I never understood the bulk ink thing, unless you were running two shifts or something. I got out right before the Mutoh ink switch, but Signwarehouse had a decent OEM replacement ink that was a few bucks cheaper than Mutoh's.

If they were 30" inches instead of 24" they'd be worth their weight in gold. Very underappreciated little machine—It weighs 70lbs and is only like 4' feet wide. Perfect first machine if you can run with the size.

 

[Racegrafix]

What does the print look like? Or what issues are making you think it has air from cartridges?

I had a 628 for about 2 years and it ran trouble free except right before I sold it the pump off the maintenance station (between the captop and waste bottle) clogged up. Not only will you have missing nozzles, etc., but if you've been paying attention to the sound of things, you'll hear that it's not activating/sucking when it's supposed to. I had to manually pull a few cups of cleaning fluid through the pump to get it running again. Solventinkjet will sell you a syringe/plunger and tubes if you need them. Once I had the pump cleaned out it ran like a top again. Never permanently lost a nozzle or had any deflections. The guy I sold it to is still running it like crazy too.

I don't think the 628 includes a pump in their maintenance station, so you will want to clean it yourself if you can.


On a side not, the thing was a sipper on ink. I never understood the bulk ink thing, unless you were running two shifts or something. I got out right before the Mutoh ink switch, but Signwarehouse had a decent OEM replacement ink that was a few bucks cheaper than Mutoh's.

If they were 30" inches instead of 24" they'd be worth their weight in gold. Very underappreciated little machine—It weighs 70lbs and is only like 4' feet wide. Perfect first machine if you can run with the size.

The bulk is just cheaper by far, thats the only reason..probably 1/5th the cost. The prints are fine minus the two color with air in lines.

I ordered an OEM cap to try that. I can see the ink has moved overnight after cleaning the cap on it extensively. Does it have lines connected to the cap? Thats what I picture but unsure.

 

[Saturn]

The pump off the captop should have three tubes I think, two drain and one breather. There's not much you can mess up, unless you actually snap off plastic pieces using too much force, so it pays to kinda poke around in there and learn how and where those tubes go. Most frustrating thing is "unlatching" the captop while making sure all the tubes stay attached and dealing with the big spring. Take pictures to remind document where things all go. If you Google "Mutoh captop replacement" you get videos like this, which can be useful.

Another indicator of the drain side being clogged, is if immediately after a cleaning cycle there's still any ink in the captop. Or if you put some cleaning fluid in it, run a clean, and there's still fluid sitting there.

Just as a point of reference, I would clean/swab my captop, wiper, and around the head at least a few times a week.

 

[Racegrafix]

The pump off the captop should have three tubes I think, two drain and one breather. There's not much you can mess up, unless you actually snap off plastic pieces using too much force, so it pays to kinda poke around in there and learn how and where those tubes go. Most frustrating thing is "unlatching" the captop while making sure all the tubes stay attached and dealing with the big spring. Take pictures to remind document where things all go. If you Google "Mutoh captop replacement" you get videos like this, which can be useful.

Another indicator of the drain side being clogged, is if immediately after a cleaning cycle there's still any ink in the captop. Or if you put some cleaning fluid in it, run a clean, and there's still fluid sitting there.

Just as a point of reference, I would clean/swab my captop, wiper, and around the head at least a few times a week.

Awesome info guys, you guys are extremely helpful.

 

[Racegrafix]

Just a follow up for anyone else, the cap top was the issue, and its back printing perfectly now.
Huge thanks to everyone.

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