How-To Guide :: Soft Serve :: Replacing Standard Gearbox

Spaceman soft serve machines use a belt-drive system where a motor is connected via a belt and pulleys to a gearbox that turns the auger in the freezing cylinder to agitate the product.  Occasionally, these gearboxes need to be replaced.  This article will go over the steps on properly replacing your gear box.  This article refers to standard gearboxes on models without a belt-driven air pump.  For instructions on replacing gearboxes on models with an air pump, please see the SS: Replacing Air Pump Gearbox article.

 

1. Flathead screwdriver
   
2. Philips head screwdriver
   
3. Metric Hex driver or Allen key set
   
4. Metric or adjustable wrench set
   
5. Metric Socket set
   
6. Needle Nose Pliers

How to Replace Gearbox

1. Turn off and unplug the machine.  
   
2. Follow the instructions in the Operator Manual to properly drain, disassemble, and clean the machine.  This process cannot be performed when the machine is assembled.
   

3. Using a flathead screwdriver move quarter-turn panel locks to unlocked position and remove side panels and rear panel as able.
   
4. Using needle nose pliers to pinch the tensioning post, and an adjustable wrench or socket, loosen the tension on both motor mount springs to loosen the belt tension.
   
5. Remove the belt from the pulleys and set aside.
   

6. Locate the two set-screws on the large top pulley attached to the gearbox.  Use an appropriate allen wrench to remove the two set-screws (3mm or 5mm depending on model).  
   
7. Install one of the set screws you just removed into the center set-screw hole on the pulley bushing.  Tighten until the pulley and bushing separate.
   

1. Tightening down this set screw can sometimes seem difficult.  Apply additional pressure until you feel set screw loosen the pulley assembly come free of gear box.  
   

8. Remove the pulley and bushing from the gearbox, and set the set screws aside.
   
9. Use a large socket or adjustable wrench to remove the four bolts from the gearbox mount.  Take care while loosening the last bolt as the Gearbox will fall off without support.  
   

1. Machines utilize a 12mm, 13mm, or 14mm bolt-head depending on model. 
   

10. Separate and remove the gearbox and gearbox mounting bracket.  Notate orientation of gearbox and mounting bracket.
    

11. Clean the gearbox mounting bracket and inspect for cracks or damage that would require replacement.
    
12. Install new gearbox to the mounting bracket and place assembly into the machine, holding in place by lightly attaching all four mounting bolts.
    
13. Using the appropriate socket or adjustable wrench, tighten the four mounting bolts in a cross pattern.  While tightening, ensure gear box remains centered to mounting bracket, and mounting bracket stays centered to rear of cylinder.  Bolts should be torqued sufficiently, however, take care not to over-tighten.
    
14. Reinstall the gearbox pulley, and place bushing inside center of pulley and align.  The gear box pulley should be directly in-line with motor pulley below.  
    
15. Install set screws into the two side holes on the bushing, attaching the pulley to the bushing.  Prior to tightening, check again to ensure gearbox pulley is inline with the motor pulley below and adjust, as necessary.
    

16. Inspect the belt for excess wear or damage and reinstall the belt on the pulleys.  
    
17. Check belt tension.  There should be approximately +/- 0.5 inches of play in the belt.  
    
18. Using needle nose pliers to hold the motor tensioning shaft and an appropriate wrench or socket, tighten the motor mounting springs until the belt tension is set correctly. 
    

19. Lubricate and install drive shaft and drive shaft gasket into cylinder.  This will ensure the gearbox is aligned correctly to the freezing cylinder.  You should be able to turn the belts by hand and not feel or hear any binding, grinding, or other noises.
    
20. Plug in and power on the machine.  press the RESET button and then WASH button.  
    

21. Inspect the belt and pulleys to ensure the belts are not binding, running vertically, and the pulleys are not wobbling.
    
22. Using a clamp-style amp-meter, check the amperage on one leg of the motor power.  Amperage will differ depending on the motor, but should generally be around 1.0 Amps.
    
23. Press RESET to stop the machine operation.
    
24. Re-install and secure outer panels.