MP C2500 Fuser Belt Tearing

[ABS tect]

I work on 2500/3000 fusers all the time and have rebuilt a lot of them. Lately though i have been getting the same issue over and over again and i am wanting to know if anyone can point me to the culprit that might be causing this issue or if it is just coincidence. I have in front of me about 5 fusers all with a torn belt. However, the interesting thing is they are almost all torn in the same section...if you are looking at the fuser, and the heating roller is facing towards you (sorry i couldn't get a picture) the left side of the belt is torn. And it almost seems like the belt slowly works its way to the right (the end where there arn't any gears) and then it gets tore up. My gut is saying either the tension roller or the pressure roller bearings...any advice to prevent all these belts from tearing?

[ruben]

Re: MP C2500 Fuser Belt Tearing

Most of the time this is caused by an over heat on the rear of the fuser (rear being the side facing away from you when the fuser is in the machine), causing the black bushings to melt and the belt to move.

It can also be caused by the foam roller coming loose from the shaft. You can tell if you manually turn the belt, and if it skips, then the roller is damaged. Or, take the roller out and look at the edges, if the foam is twisted or coming away from the shaft, then it needs to be replaces.

If the fuser is old, then you may also have a twisted frame, but this is rare.

I very rarely replace the tension roller, usually a good clean is needed.

[NeoMatrix]

Re: MP C2500 Fuser Belt Tearing

Try stretching the springs on the fuser belt idler roller, which will place more pressure on the belt.

I've seen fuser belts slip very easily over the drive rollers with out even turning the gears.
If you're reusing the idler rollers in a fuser rebuild it may pay to replace them every 2nd fuser rebuild.
The diameter of an old fuser idler roller is slightly reduced, adding to the loose belt, so they need to be replaced.

HTH

[TonerMunkeh]

Re: MP C2500 Fuser Belt Tearing

Just put B230KFUSA in and replace the thermistors. Then you pretty much have 5 brand new fusers.

[ABS tect]

Re: MP C2500 Fuser Belt Tearing

Try stretching the springs on the fuser belt idler roller, which will place more pressure on the belt.

I've seen fuser belts slip very easily over the drive rollers with out even turning the gears.
If you're reusing the idler rollers in a fuser rebuild it may pay to replace them every 2nd fuser rebuild.
The diameter of an old fuser idler roller is slightly reduced, adding to the loose belt, so they need to be replaced.

HTH

Now the black bushings on all of them seem to be fine...i have had a lot that have gotten melted but these are not. Now i will definitely replace the idle roller but i am a bit confused about the spring. The only springs i know of on this machine are for the lock levers and tension roller...and wouldn't stretching a spring create less pressure? I guess i am misunderstanding you.

[NeoMatrix]

Re: MP C2500 Fuser Belt Tearing

Now the black bushings on all of them seem to be fine...i have had a lot that have gotten melted but these are not. Now i will definitely replace the idle roller but i am a bit confused about the spring. The only springs i know of on this machine are for the lock levers and tension roller...and wouldn't stretching a spring create less pressure? I guess i am misunderstanding you.

If the idler/tension bushes look fine,it may help to stretch the tension spring just a tad.
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AA06 3952 Compression Spring:Belt Tensioner 2

If it were my fuser unit causing a problem, I might file/grind a bit more out of the tension slot metal frame to
increase the tension roller travel. If it's a customers machine then replace the problem fuser.

[BLADE]

Re: MP C2500 Fuser Belt Tearing

I,d guess the one way drive gear is on backwards

[Mark Bbb]

Re: MP C2500 Fuser Belt Tearing

Having the same problem here. In that case I replace the tension roller springs and the tension roller. I've had this problem now only since 1 year. It happens also on a c2800 that has only 110K on the counter! So, it is not "the using" that is causing it, but "time". Indeed in time these springs get less powerfull, that is why I replace them. But it's funny that only since the last year we have seen this trouble!

[ABS tect]

Re: MP C2500 Fuser Belt Tearing

Thanks so much for all of your help! I understand now what you are saying about stretching out the springs. I went ahead and stretched out those tension springs, as well as replaced all the bearings and gears with new ones. The new fuser is running good so far so lets hope that does it! Thanks again to all who helped