Precise details:

Descriptions:

The small model was built from copper castings, Water is pumped through a water jackets to cool the engine . you can run it for a long time.
To start the engine, simply fill the gas tank with butane gas, turn on the gas valve switch, ignit the boiler under the engine, add about 80ml of water to the water tank, heat it for about a minute, and then start the engine by hand-cranking the flywheel.

Feature:
Educational & Scientific Insigh:

Understand the principles of external combustion engines through a fully functional, miniature model. Ideal for classrooms, tech enthusiasts, and anyone curious about mechanical science. Compact & Reliable Design:

Made with durabl brass and wood, featuring a modern water-cooled circulation system that keeps the engine running smoothly and safely. Uses butane gas for clean, efficient fuel. Easy to Use & Maintain:

With minimal moving parts, this engine offers stable operation, low wear and tear, and simple maintenance—making it perfect for beginners and experienced modelers alike. Simple Startup:

Just fill the gas tank with butane, open the valve, ignit the boiler, add water, heat for a minute, and spin the flywheel by hand to bring the engine to life. Watching it work is truly mesmerizing! Unique Gift & Desk Decor:

Whether as a striking conversation piece or an impressive gift for teachers, students, or collectors, this engine model adds charm and intrigu to any desk or display shelf. 

Specifications:

Brand: OKMO

Item No.: R01
Item Name: 1/12 Stirling Hot Air Pump Engine
Material: Brass + Stainless Steel + Aluminum
Colour: RED/Green
Flywheel Diameter: 56mm
Start Method: Manual

Form: Ready to Run
Cyilinder Diameter: 13mm

Stroke: 24mm
Speed: 100-1000rpm(A continuous running time of 15 minutes on a single gas tank.)
Cooling Mode: Water Pump Cooling
Product Weight: 900g
Package Dimensions: 20 x 20 x 20cm

Product Weight: 1350g
Product Dimensions: 125mm x 75mm x 128mm
Package Weight: 1350g
Packing: Box
Ages: 14+

Package included:
1x Stirling Hot Air Pump Engine Model

Q&A:

Q1: Why won’t my engine run smoothly when I start it?

A1: This usually happens because of incorrect fuel mixture or insufficient lubrication. RETROL R01’s precise mechanics require the official recommended fuel and lubricant. Using the wrong type reduces combustion efficiency, causes rough starts, stalls, or even damages the piston and crankshaft. Proper oiling is essential for performance and longevity.

Q2: What happens if I use the wrong fuel? A2: R01 requires fuel with specific volatility and lubrication qualities. Using improper fuel (like regular gasoline or low-quality fuel) leads to poor combustion, carbon buildup, engine jams, or overheating. Lack of lubrication accelerates wear and can cause early failure. Stick to the recommended fuel to ensure smooth power and protect parts.

Q3: Why does the engine suddenly stall after starting? A3: Stalling usually means a blocked oil circuit or unstable fuel supply. Bent fuel lines, loose fittings, or clogged filters restrict flow, causing power drops or flameouts. Regularly check and clean fuel connections to keep it running steady.

Q4: Why does my engine make strange noises or vibrations while running? A4: This usually  points to low lubrication or loose parts. R01’s metal gears and pistons need sufficient oil to prevent friction and vibration. Also, loose screws or mounts cause noise. Always lubricate well and tighten all fasteners to keep it quiet and smooth. Q5: Why does engine power drop after a short run? A5: Power loss can result from incomplete combustion, carbon deposits, or lack of lubrication. Regular cleaning and timely oiling are necessary to maintain efficient operation and avoid excessive wear. Q6: Why doesn’t the engine spin smoothly when I try to start it? A6: Even though RETROL R01 comes fully assembled and tested, factors like dirt or debris inside the moving parts, or insufficient lubrication can cause resistance and make the engine hard to turn. Ensure the engine is properly lubricated before starting, keep it clean, and check that nothing is obstructing the flywheel or piston movement. If problems persist, contact support for inspection. Q7: How do I maintain R01 for long life? A7: Keep fuel clean, lubricate on schedule, clean carbon deposits regularly, and check all fasteners. Proper maintenance prevents wear and keeps performance consistent. Always use official fuels and lubricants.

Q8: How do I start the R01 correctly? A8: Follow these steps: 1. Fill the fuel tank with butane gas, open the valve moderately. 2. Add about 80ml of clean water to the cooling tank. 3. Light the boiler below the water tank to heat water and generate steam—wait about 1 minute for pressure buildup. 4. Gently turn the flywheel by hand to overcome startup resistance. 5. Adjust the fuel valve for stable combustion and smooth running. Why this matters:

Proper steaming ensures enough pressure to move the piston. Water cooling prevents overheating. Turning the flywheel too early or improper valve settings cause startup failure or damage.