MP 2851 Jam Code 020

[Foo]

PLEASE READ ENTIRE POST BEFORE OFFERING SUGGESTIONS...thanks!

Interesting morning today... MP 2851 w/finisher SR790 and bridge 3rd drawer LCT. 102K on the meter. First call out on it since delivery.
Odd intermittent J020 errors.
I get "why" the error, but the cause has me scratching my bald spot.

First I wanted to see exactly what was happening when the J020 came up.
Hit the button and 8 1/2 x 11 paper left the drawer, went vertical, entered the lower fuser, but never went in between the UFR or LFR.
It appeared the fuser is not turning to pull in the paper. I removed the fuser, dis-assembled, inspected for a cracked fuser drive gear (not cracked).
Removed the entranced ramp an checked for wear or burrs keeping paper from entering the fuser. Also there is no damage marks on the lead edge of the paper.
Next I checked the swivel gear that drives the fuser drive gear. It's in perfect condition.

Removed the bridge unit and finisher...no change still jamming.

So now the weird stuff...
Reinstalled the fuser...still jamming. Unplugged the exit assy above the fuser...still jamming at fuser.
So I take the rear of the machine off to watch the gears driving the fuser. I touch nothing, just watch with a flashlight.
Hit the copy button...passes paper. Hummm, OK lets do a small run, 50 sheets. No issues. Customer prints some needed stuff...no issues.
Send a Fax...no issue. Print some more junk...working fine. I plug the exit assy back in...still printing and copying fine.
Shut off machine, reinstall rear cover. Customer says..."watch it not work". Normal reboot. Try to copy...jam at fuser J 020.
I remove the paper inspect it...lead edge clean just like the 75 previous jams. Though to myself "wonder what happens if I run from a different drawer".
Pick Tray 1...8 1/2 x 14 paper goes right through. Switch back to Tray 3 LCT drawer it makes a couple. I stop and reinstall the bridge unit and finisher.
Tried for 2 more hours and never got another piece of paper (of any size or any drawer) to pass. When it was running, it ran like silk, with no noises or complaints. When jamming, the paper always entered the fuser but would not pass on to the LFR UFR. I even removed the shutter from the PCU, just in case...made no difference.

I realize the J020 error is an exit error. And the reason for the error is that the paper never makes it to the exit switch.
But it can't because it stops before it makes it into the fuser.

First time in a long time I'm stumped on this style of machine.
Just had to install that fuser swing gear on one of these (different machine) 2 days ago...first time for that job too.

Total call time: 3+ hours
Customer Satisfaction: 0

Any help or ideas would be great.

Jeff in STL

[copyaction]

Probably not with this low meter, but when the press roller goes soft it will jam there without entering the fuser

[Polarbear]

Hi

dodgy fusing solenoid maybe? I know these solenoids tend to become sticky over time. Strip clean and refit.

[Foo]

Back after a interesting day in the field.

So I went back to this call this morning.
Started with the "replace the LFR" suggestion. That didn't help but not a bad idea and worth a try.

Next the solenoid...Opened the rear cover and removed enough main board connectors to fold down the main board just enough to get to the solenoid.
I had pushed the fuser drive gear that's on the swivel yesterday and thought it felt sticky. Really have no idea how, in conjunction with the solenoid, it's actually is supposed to work. Removed the solenoid and used a swab stick and cleaned up the plunger and the inside of the solenoid. Applied just enough lube to say I lubed it (really hardly any at all). The gear swivel seems to move nicely with very little effort. Reinstalled the Main board and tested. I watched the solenoid using a flashlight and push the copy button. Paper comes out of the drawer hit the Reg. roller stops...then continues up to the fuser. Then folds in half never entering the fuser. This whole time I'm locked in on watching the solenoid...it never moves. I try several more times and no success and no movement of the solenoid. I do notice the solenoid is in the pulled in "released" position. So that means the swivel isn't pushed up against the fusers drive gear...progress!

So I notice there's a spring steel band behind the swivel gear assy. I reach in with needle nose pliers and tweak the spring steel to ride up against the swivel assy. frame. That pushes the gear noticeably towards the fuser. Reinstall fuser and boom copies. Lots of testing and no issues.

BUT!!! I know this is a temporary fix. The solenoid is supposed to be doing what the spring I just tweaked is now doing. I went to the output section in tech mode and did a test of the solenoid and it did not move.

I know that spring isn't going to hold out for long.

So I'm ordering the solenoid to start. But was wondering if anyone could walk me through what that solenoid does and why. What triggers it. When it should be in the outward "engaged" position. And why it needs to be able to be in a "Released" position.

Thanks...look forward to hearing about how this works.

Jeff in STL

[copyaction]

This was very common on the 1027 and 2027 series, that leaf spring always needed to be "formed" forward to engage the fuser drive gear

[Foo]

But isn't it the job of the solenoid to push the gear in the swivel towards the fuser drive gear?
The solenoid in this machine doesn't move...or at least I haven't been able to actuate the solenoid.

[DougD]

This is just a hunch, but after reading your entire thread, I would be inclined to swap in the duplex unit from a working machine as my next course of action.

[copier tech]

The solenoid is there to release the fuser drive to make it easier for the customer to remove a jam.

They can become magnetised & stop working.

Simply replace it with a new one.

[totoro]

Just a question to verify my understanding. Is the plunger pulled in because the solenoid is on and holding it in? You don't mention anything about the spring that usually holds the plunger in the pulled out position. If the solenoid is powered all the time it, is either the solenoid or the board it gets it's signal from. (bicu?)
I remember dealing with the spring steel band you mention and did just what you did and had no other problems. It could be just as Copier Tech says. I'm not sure if I ever looked at the solenoid you're referring to. I guess I would look at a working machine to verify what you suspect.

[Foo]

Seeing that the solenoid is cheap and the customer is expecting me to return with a part...think I'll order 1 and pop it in.

Let you all know what happens.

Jeff