Sharp Model MX-3501N

**Tech2002** · 09-26-2008

Fuser issue with this model. Before system reached even its first 100k of usage the fuser started with a clicking noise. Re-seated unit - this was with two different systems by the way, system made same clicking noise. Changed Web Cleaning Roller - still clicking noise. Checked all gears - look good and moves well. When I opened up the Fuser Pressure Levers noise stopped. I can't figure what else to do less pulling Fuser apart and start replacing gears. I actual ended up replacing both fusers.

Any input? Greatly appreciated.

**NCArt** · 09-26-2008

If the machine has set for awhile, the pressure roller flat spots, there is a tech tip that was written about it. I advise all of my Pastel customers that if they are going to be gone for a long weekend, to relieve the pressure before they leave. On the new 2600/3100 they put a motor in that relieves the pressure when not in use.

**Comingapart** · 09-26-2008

It's a bearing issue.
You can re-lube the bearings with a particular grease, but that doesn't really help for any length of time.

They just do this, as of now there is no good fix.

**Tech2002** · 09-26-2008

The clicking noise I am referring to is that it sounds like a gear is hanging up, that the fuser is trying to move but is hung up. This makes sense when I have taken the pressure off the primary roller by releasing the pressure levers.

It is strange that I have two identical machines with the same issue. Would changing the barings or the main gear be advisable or helpful?

Thanks for the replies.

**NCArt** · 09-26-2008

I would look at the pressure roller first...if it is flat, it will be real obvious. I had 3 machines with this problem before I figured out what caused it.

**blackcat4866** · 09-26-2008

You're going to hate this but it works. Get Molykote HP-500 high temperature grease (part # UKOG0235FCZZ). There are small tubes, so you will only get a few fuser treatments from each tube.

Disassemble the fuser. Grease the contact surfaces between the driven roller and its bearings, and the non-driven roller and its bearings. Re-assemble the fuser. You won't be able to adequately lubricate the surfaces without disassembly. Don't get any grease on the heat lamps or they may blow.

The good news it that it will last the whole PM cycle without ticking. Just save yourself some time and lubricate the bearing surfaces when you are rebuilding the fuser.

I have had very little problems with the ticking since I've started doing this at the rebuild. Sharp came up with some kind spray lubricant, but I could not bring myself to use it. It's just too risky spraying lubricant near the ends of the roller. =^..^=

OMD-227 · 09-28-2008

easy one guys....

I see this all the time....

The problem is with the spacing on the UHR & LHR each side of the bearings. Sharp has updated the UHR & LHR kits to include several spacers on each side of the bearings. This holds the bearings square alot better on the roller shaft and prevents the clicking noise.
Of the many fuser units I have installed the new modified rollers into, I have had almost all of them do their full 300K without any problems. Infact, most have been reset at 300K and still going well (after replacing web unit of course).
Here is another well-used fix.......
If you dont have the new modified rollers or the individual spacers available to you yet, take the pressure off the rollers with the pressure lift levers, remove all side covers of the fuser, then rotate the bearing casings (outside part of the bearings) 180degrees from where they were to begin with. Example.... use a flat blade screwdriver, press against the outside of the bearing casing and turn the casing around half way.
I have found this to be a very effective fix if you dont have the new rollers or spacers in stock.... plus its alot quicker than dismantling the fuser to change otherwise good rollers.
These are the same fuser bearings as the Dragon series. The UHR & LHR were made just a fraction too long and the bearing has nothing to hold it square on the roller shaft.
I also agree with Blackcat's grease use. This has also worked for me.
The new mod fuser rollers or turning the bearing casings around are used almost every day here with great success.
This is only for the clicking noise. If you have a thumping noise on each roller rotation, you have a flat-spot due to machine non-use. Replace the fuser rollers, update to latest firmware which has a function to rotate the fuser each Midnight, therefore preventing the flat-spot. The machine obviously needs to be in sleep-mode overnight, and not powered off. This has reduced my UHR & LHR stock for flat-spots very, very much. Just explain all of this to your client. They should be cool with it.

**Tech2002** · 09-28-2008

I appreciate the input from everyone! Thanks!

**Tech2002** · 01-26-2009

I took the fusers apart as suggest - just got around to having to actually do this.

When I took them apart I cleaned - srubbed the ends of the Fuser Shafts with a rubber rejuvenator cleaner (careful - very strong smelling chemical) & Scotch Guard Pad - Works wonders. I then went to Graingers and bought I Chaulking Gun size Tube of High Heat Resistant Grease able to handle heat in excess of - I think it's 400 + degress - Cost - $50.00. Sharp has a small tube, less than an once for $50.00. Only issue with Grainger's Special, it's black and can be messy. If you use this method I'd suggest seeing if you can get if in White or Clear. Because of a gap between the Bearing and the Shaft, there is Carbine that builds up on the Shaft itself. When I went to take the Bearing off I needed to let the cleaner loosen the Carbine build up because there was so much on it that they wouldn't come off. Covered Bearigs and the Shaft with the Grease.

Got it completed on another just the of the other day. I did just ended up doing the Lower Heat Roller. Stopped the noise.