Hard to say what your cause is without knowing the age of the motor -
Here are your starting points -
1 -The grease lubrication of the motor gear is not enough. Most unlikely
2. Motor is broken/Life. **
3. Servo Board is broken. **
4. Tool Carriage fixation to the belt is loose.
thanks mate ill pop the hood and have a fiddle then
any ideas how to access that motor
what is worrying though is the motor is turning the bottom steel roller fine . so would it not
be a servo board problem
The board might be not reading it or a sensor issue. check cabling.
You should run the PECK program that is on rolands web site. This program will create a file with all the statistical data of your printer.
In this case we want to see the hours on the feed motor. This will give an indication of how old the motor is and the probability of it being the issue.
This is an high level maintenance action and warrants a service call which I think you already alluded to.
In any case I think you have taken it as far as an operator can safely troubleshoot.