top of page

OOLS Service & Repair Scheme

Standard Operating Procedure

Unlike the majority of the free information provided on this site the Service & Repair scheme will involve a cost to the user so it is important that we make it clear how scheme is structured and what levels of work will be undertaken each stage.

The OOLS Service and Repair Scheme consists of two parts.

  • Routine Service - includes consumable spares and completed as per the Standard Operating Procedure

  • Repairs - Work and/or parts required in addition to the Routine Service

Experience has shown that it is rare for a loco to only need a Routine Service and the majority require some form of additional work/parts for them to be restored to full working order. Any locos requiring a repair will also need to be serviced.

Members should bear this in mind before deciding to use this scheme.

Standard Operating Procedure

The service & repair process may be carried out by different people so the club have developed a Standard Operating Procedure to ensure that every service is carried out to the same professional standard. This lists all the service actions that will be carried out on each individual loco.

Initial inspection: 


  1. Inspect the general condition of the loco for damage and missing parts. 

  2. Remove the loco body and generally inspect the mechanism for damage and missing parts. 

  3. Photograph and note any damage and areas of missing parts. Notify the customer and get an acknowledgement before continuing. 

  4. If the loco looks runnable, power up on compressed air or steam on a rolling road or track to make an initial assessment of its condition. 

 Static checks: 


  1. Clean the loco body. 

  2. Generally clean off excess oil around the loco mechanism, check for visible faults. 

  3. Check the visible seals condition; oil and water fillers. 

  4. Remove the rotary valve housing and check the condition of the valve and thrust pad. 

  5. Replace the rotary valve housing gasket. 

  6. Replace the super heater gasket. 

  7. Replace the piston seals. 

  8. Tightness of all screws, including the two screws under the front bogie that secure the steam chest and rotary valve housing to the chassis.

  9. Inspect the lights board and wiper + clean the wiper and board.  

  10. On the A4's inspect the rotary valve housing screw points. The housing is plastic and prone to cracking. 

  11. Check and clean the magnets on the regulator motor. They can collect and build up metallic debris and cause the motor to stall. 

  12. Check to carbon brush housings on the motor pushed fully home. 

  13. Check the alignment of the exhaust ports on the top of the relief valve. 

  14. Check the general condition of the PCB for broken wires, dry joints or corrosion on the soldered joints. On the A4's check the common connection that terminates onto one of the screws at the base of the relief valve. 

  15. Check the tender/loco connecting cable plug/socket for discoloration caused by overheating. 

  16. Check the condition of the wires connecting the lights board. They are prone to burning if fastened too close to the super heater. 

  17. Check for play on the reduction gearbox worm and crown wheel bearings. 

  18. Lubricate the reduction gearbox parts and bearings, particularly the two worm and crown wheels. 

  19. Check the security of the final drive worm wheel for the regulator drive. 

  20. Check the timing adjuster mechanism that it has not loosened from the main timing shaft. 

  21. Remove the front and rear bogies, strip off the wheels and axles, clean and re-lubricate. 

  22. Clean all the connecting rods and crank pins and re-lubricate. 

  23. Check the connecting rods are not bent or interfering anywhere. 

  24. On the underside of the loco remove the plastic cover on the chassis and check the tightness of the differential gearbox screws. 

  25. Oil the driving wheel axles and bearings. 

  26. Check the tightness of the driving wheel nuts, rotate the wheels and check any misalignment or run out. 

  27. Remove, dismantle and refurbish the tender wheels and check the condition of the bearings for free movement.  

  28. Remove the power collectors and polish the contact areas including those on the brass wheel housing plates.  

  29. Polish the bearing housings to a bright finish. 

  30. Polish the U shaped copper contacts on the tender/loco connecting cables. 

  31. Clean the tender body. 

  32. Re-assemble but do not oil the bearings.


Running checks: 


  1. On the rolling road while building steam pressure operate the regulator motor to check for free movement, rotate the regulator driving gear wheel through 360° in both directions. Use the main controller and the Live Drive controller 

  2. While doing the above, check that the forward/reverse gear shifts accordingly. 

  3. When steam pressure is achieved look for steam/condensate leaks before opening the regulator. i.e. the loco/tender connecting pipe, the relief valve. 

  4. With the regulator closed check that no excessive steam exhausts from the whistle or the chimney. 

  5. Observe that the relief valve operates normally. Use a pressure gauge and note the blow off pressure. Adjust if necessary to 2 bar. 

  6. Open the regulator fully to make sure the loco runs at full speed, both forward and reverse. Let the loco get hot. 

  7. Stop the driving wheels with the regulator still fully open. Look/listen for excessive steam exhausting from the chimney. 

  8. Gradually slow down the loco as slow as it can before stopping and check for the timing condition, forward and reverse. Adjust the timing if necessary. 

  9. Check the whistle operation. 

  10. On refitting the main body check that the wiring does not interfere with the main driving wheels or the spur gears for the motor reducer. 

  11. Transfer to a layout and run under load to observe the general performance of the loco. 

  12. Allow the loco to cool completely for several hours and repeat the test on the layout. 

T&C Button.175png.png
bottom of page