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Richards
07-02-2015, 03:33 PM
I had a fuser unit in a KM c450. The stripping fingers on top of the fusing roller were gouging the roller. It was near its life limit; so I replaced it with a 'used' fuser (bad idea) It worked for only a few impressions when these stripper fingers began to gouge the fuser roller. Now I am going to replace this one with a new fusing unit, but want to be sure that this new one does not get gouged as well. Could I be dealing with a worn gear? What else could it be?
Thanks

allan
07-02-2015, 05:21 PM
Is it making a noise? Wait for the machine to be cool. Check the gears. But there is not really suposed to be any source outside of the fusser that would cause the pawls to scratch.

So if the machine is not making a noise and if the gears aint loose stick the new one in.

EarthKmTech
07-02-2015, 11:16 PM
some kind of aftermarket toner in use destroying the fuser ?

Richards
07-03-2015, 12:29 PM
Is it making a noise? Wait for the machine to be cool. Check the gears. But there is not really suposed to be any source outside of the fusser that would cause the pawls to scratch.

So if the machine is not making a noise and if the gears aint loose stick the new one in.

Thank you for the info. Every now and then there is a slight noise. I have not tracked it down, but will today. Does the fuser roller swell as it ages?

Richards
07-03-2015, 12:31 PM
some kind of aftermarket toner in use destroying the fuser ?

I pretty sure I buy oem toner, but I will check that out. Thanks

EarthKmTech
07-03-2015, 12:36 PM
c450 is a belt fuser, on the other side the pressure roller clear coat blisters, wrinkles and peels off due to minutes accumulated while hot regardless of pages printed before total destruction. Never seem them swell.

blackcat4866
07-04-2015, 12:29 AM
Do you have an adequate lead edge void (3mm or more)? Does your enduser do heavy fill images?

Lack of leading edge void can cause more accordian jams in the fuser claws. Many multiple prints of heavy fill images can also can also cause more accordian jams at the fuser claws. Accordian jams in the fuser are the usual cause of heat belt gouging. You can adjust the leading edge void, but there is not a lot you can do about the heavy fill originals, except making shorter runs and alternating images with lighter fill. =^..^=

EarthKmTech
07-04-2015, 07:33 AM
Do you have an adequate lead edge void (3mm or more)? Does your enduser do heavy fill images?

Lack of leading edge void can cause more accordian jams in the fuser claws. Many multiple prints of heavy fill images can also can also cause more accordian jams at the fuser claws. Accordian jams in the fuser are the usual cause of heat belt gouging. You can adjust the leading edge void, but there is not a lot you can do about the heavy fill originals, except making shorter runs and alternating images with lighter fill. =^..^=


This man knows exactly what he's talking about (hope really not a woman, i dont know)

I saw this recently on a 654 series, it still happens to this day and thought, gee, I havent seen this in YEARS since i used to work on HP laserjets in the 90s.

blackcat4866
07-04-2015, 01:53 PM
... (hope really not a woman, i dont know) ...

Most stick with "cat", but yes I am a man last time I checked. =^..^=

Richards
07-04-2015, 08:38 PM
Do you have an adequate lead edge void (3mm or more)? Does your enduser do heavy fill images?

Lack of leading edge void can cause more accordian jams in the fuser claws. Many multiple prints of heavy fill images can also can also cause more accordian jams at the fuser claws. Accordian jams in the fuser are the usual cause of heat belt gouging. You can adjust the leading edge void, but there is not a lot you can do about the heavy fill originals, except making shorter runs and alternating images with lighter fill. =^..^=

Thanks. There have been few accordian jams - none since I installed this newer 'used' fusder.

This machine runs mostly b&w, 12 x 18, 24# through the bypass. What I did notice is that when there is a jam about a 1/3 of the sheet is through the fuser. To remove the sheet, it is being pulled down (opposite the normal direction) You can hear the gears jump. Could the sheet be being removed wrong?

I did tear the machine down to the gear assembly and it all looks good from what I can tell.

Any help is really appreciated.
Thanks

blackcat4866
07-04-2015, 09:09 PM
Thanks. There have been few accordian jams - none since I installed this newer 'used' fusder.

This machine runs mostly b&w, 12 x 18, 24# through the bypass. What I did notice is that when there is a jam about a 1/3 of the sheet is through the fuser. To remove the sheet, it is being pulled down (opposite the normal direction) You can hear the gears jump. Could the sheet be being removed wrong?

I did tear the machine down to the gear assembly and it all looks good from what I can tell.

Any help is really appreciated.
Thanks

As you know it's preferable to remove the jams in the paper feed direction, but sometimes it's just unavoidable to pull out a page against the feed direction. It doesn't do any damage to the gears. The risk is that one of the flags will poke through the paper, then that flag gets broken or dislodged as the paper is pulled. It's less likely on the 24#, since it's harder to pierce the heavier media.

You haven't mentioned leading edge voids or fill yet. Did you miss the point? =^..^=

Richards
07-05-2015, 10:32 PM
As you know it's preferable to remove the jams in the paper feed direction, but sometimes it's just unavoidable to pull out a page against the feed direction. It doesn't do any damage to the gears. The risk is that one of the flags will poke through the paper, then that flag gets broken or dislodged as the paper is pulled. It's less likely on the 24#, since it's harder to pierce the heavier media.

You haven't mentioned leading edge voids or fill yet. Did you miss the point? =^..^=

Thanks for the reminder. I did not think the lead void area was the issue since there were few accordian jams. On second thought, HOWEVER, when using the 12 x 18, 24# paper there are registration marks that do not print entirely because they are too close to the edges. In addition, a 12 x 18 100# coated text sheet is printed sometimes (less than 10% of the total copies). These copies do have very large fill areas.

So how do I adjust the lead edge void area? Is it in the print area adjustment?

Many thanks

blackcat4866
07-06-2015, 12:36 AM
Service Mode > Machine Adjust > PRT Area > Top Margin

Book specs are 5.0mm +/- 0.5mm. The heavier the fill, the larger the lead edge void that you'll need. =^..^=

Richards
08-02-2015, 08:32 PM
Put a brand new fuser in. It ran about 20,000 copies and the fuser went bad again. The lower fuser roller peeled on the operators side. I understand that this model tends to not make its life expectancy, but 20M copies is too low - I would think.

Could it be getting too hot???? Sorry but I am new at this and frustrated.

Any help is appreciated!!! Thanks
Rich

blackcat4866
08-03-2015, 12:33 AM
Put a brand new fuser in. It ran about 20,000 copies and the fuser went bad again. The lower fuser roller peeled on the operators side. I understand that this model tends to not make its life expectancy, but 20M copies is too low - I would think.

Could it be getting too hot???? Sorry but I am new at this and frustrated.

Any help is appreciated!!! Thanks
Rich

20K or 20M?

I'll tell you the same thing that I tell every customer that tells me the machine is running too hot. Did the thermal fuse blow? Then it's not too hot. Normal operating temperature is 180C or ~350F. It's hotter than your flesh ... but so what? =^..^=

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