Sc.503

**techspec** · 03-22-2009

I have found that the timing pulley (AB03 0787, located on page 11- item no:25) requires replacing when this fault appears.

The gear or timing pulley as it is called in the parts manual has a flat section on it where it sits on the shaft, through time this rounds and the paper isn't transported properly from the left hand side of the tandem tray to the right.

Hope this helps. It took me a bit of time to find this fault because if you remove the stepper motor and drive the belt and pulley by hand it moves freely and visually it looks okay. But I would definatelly check out this gear.

**Ollie1981** · 03-23-2009

Originally Posted by techspec

I have found that the timing pulley (AB03 0787, located on page 11- item no:25) requires replacing when this fault appears.

The gear or timing pulley as it is called in the parts manual has a flat section on it where it sits on the shaft, through time this rounds and the paper isn't transported properly from the left hand side of the tandem tray to the right.

Hope this helps. It took me a bit of time to find this fault because if you remove the stepper motor and drive the belt and pulley by hand it moves freely and visually it looks okay. But I would definatelly check out this gear.

I have had this problem many a time on the MP7500 where it usually flags up SC515.

The quick indicator I always use before I get the screwdriver out is to see if I can move the tandem tray rear fence by hand. The stepper motor is geared down so much that it is impossible to move by hand under normal circumstances, if the pulley gear has rounded off then the fence will move and you will see the pulley spin on the motor shaft.

**techspec** · 03-23-2009

Originally Posted by Ollie1981

I have had this problem many a time on the MP7500 where it usually flags up SC515.

The quick indicator I always use before I get the screwdriver out is to see if I can move the tandem tray rear fence by hand. The stepper motor is geared down so much that it is impossible to move by hand under normal circumstances, if the pulley gear has rounded off then the fence will move and you will see the pulley spin on the motor shaft.

You would think that they would make the pulley of a stronger material.

Like you I have come across it in the larger machines