I have been printing 24 hours a day recently and the Y motor has been overheating so this upgrade part uses a cheapo VGA fan to cool the motor - works extremely well.
This part works with both the OB1 and OB1.4 printers.
This example was printed with a broken Y-motor mount hence the poor print quality.
Print it out at .25mm layer height and 40% fill or better.
Search Ebay for "VGA fan" and you'll find one of these for about a dollar each normally.
Connect it straight onto the 12 volt terminals from your power supply.