VW Industrial Engine Type 122: Timing Belt for the Speed Governor Explained
Many VW Type 122 engines still run today – but suitable replacement belts are rare. Here is what matters.
Timing Belt for the Speed Governor of the VW Industrial Engine Type 122
Many VW industrial engines of Type 122 are still in use today. They operate in stationary applications, in agricultural machinery, technical units or historic systems that are still expected to function reliably. Especially with such older engines, however, the supply of spare parts is becoming increasingly difficult.
One component that is repeatedly requested is the timing belt for the speed governor of the VW Industrial Engine Type 122. This belt drives the speed governor. The speed governor operates the throttle valve in the carburetor on the stationary VW Industrial Engine Type 122. If the timing belt is worn, damaged or broken, a suitable replacement belt is required.
Alphabelt manufactures this timing belt as a high-quality reproduction. The belt is not an original Volkswagen part, but a suitable replacement belt for the technical application on the speed governor. It is 10 mm wide, has 64 teeth and the reference number VW122135171A. It is manufactured from polyurethane with endless steel tension members and without a joint.
What is the VW Industrial Engine Type 122?
The VW Industrial Engine Type 122 is based on a four-cylinder gasoline engine with 1192 cm³ displacement. The engine was built for many years and was not only known as a vehicle engine, but was also used as an industrial engine for stationary drive applications.
Many of these engines were not used in road traffic, but as robust stationary drives. This is why Type 122 engines can still be found today in applications where simple design, reliable operation and easy maintenance are important.
Typical areas of application included:
- Pumps
- Firefighting units and portable fire pumps
- Compressors
- Conveyor systems
- Fans
- Welding units
- agricultural machinery
- forage harvesters and combine harvesters
- vibrating machines
- boat units
What is the function of the speed governor?
When an engine is used in stationary operation, a constant speed is particularly important. Unlike a vehicle engine, which is constantly affected by throttle position, load and driving condition, a stationary industrial engine usually has to operate constantly at a defined speed over a longer period of time.
On the VW Industrial Engine Type 122, the throttle valve in the carburetor is operated by a speed governor. The speed governor therefore performs a mechanical control function in the area of the fuel-air supply. The timing belt drives this speed governor.
Simply explained: The timing belt drives the speed governor. The speed governor operates the throttle valve in the carburetor. This assembly regulates the engine speed in stationary operation.
Why is the timing belt important for the speed governor?
The timing belt is part of the drive unit of the speed governor. It works by positive engagement: The teeth of the belt mesh with the matching toothing and transmit the movement synchronously. For driving the speed governor, this type of power transmission is important because it should take place reliably and without slip.
Like many belts, the timing belt on the speed governor is also a wear part. Over time, the material can age, become brittle, develop cracks or become damaged. Especially on engines that are several decades old or have been standing still for a long time, the condition of the belt should be checked.
If the belt is worn, damaged or broken, the speed governor can no longer be driven as intended. A suitable replacement belt is then required.
Why are suitable replacement belts difficult to obtain today?
The VW Industrial Engine Type 122 is a historic industrial engine. Many of these engines are still found today in collections and workshops or are used by fire departments or agricultural businesses. For such engines, sourcing spare parts is more difficult than for modern series products.
Original replacement belts are difficult or no longer available. Old stock is used up over time, used parts are often not reliably assessable and standard belts do not automatically fit the respective assembly.
This is why high-quality reproductions are particularly important. They make it possible to continue operating existing engines without having to rely on uncertain used parts or damaged old stock.
The Alphabelt Replacement Belt for the VW Industrial Engine Type 122
Alphabelt manufactures a suitable replacement belt for the speed governor of the VW Industrial Engine Type 122. The belt is designed as a reproduction and is suitable for use on the speed governor. It is not an original Volkswagen part.
| Product type | Timing belt / replacement belt |
|---|---|
| Application area | Speed governor |
| Suitable for | VW Industrial Engine Type 122 |
| Width | 10 mm |
| Number of teeth | 64 teeth |
| Reference number | VW122135171A |
| Material | Polyurethane / PU |
| Tension members | Endless steel tension members |
| Design | Molded timing belt without a joint |
| Manufacturer | Alphabelt |
| Note | Not an original VW part. The reference number is used for technical identification. |
Why polyurethane as a material?
The Alphabelt replacement belt is manufactured from polyurethane. Polyurethane is a proven material for technical timing belts because it is dimensionally stable, abrasion-resistant, durable and suitable for precise belt geometries.
For a timing belt on the speed governor, a clean tooth profile is important so that the belt can reliably engage with the toothing. In the case of the VW Industrial Engine Type 122, this is not just any standard part, but a belt that has to fit a very specific older assembly.
What are the advantages of endless steel tension members?
Endless steel tension members are used in the Alphabelt replacement belt. These tension members ensure that the belt keeps its shape and length as stable as possible under load.
This is especially important for a timing belt, because tooth pitch and belt length must match the application. A belt that stretches uncontrollably or does not remain dimensionally stable would be unsuitable for precise transmission.
Why is manufacturing without a joint important?
Alphabelt manufactures this timing belt as a molded timing belt. This means that the belt is not cut from open-ended material and welded, but manufactured in a specially made mold.
The decisive advantage: The timing belt has no joint. This means there is no seam, no splice and no weak point at which the belt would be structurally weakened.
When should the timing belt on the speed governor be checked or replaced?
The timing belt on the speed governor should be checked when the engine is being repaired, put back into operation after a long standstill or technically inspected. A visual inspection is also useful for historic engines, firefighting units, pumps or agricultural machinery.
Possible indications are:
- visible cracks
- brittle or hardened material
- damaged or missing teeth
- frayed belt edges
- heavily soiled or oily belt
- unclear origin or unknown age of the belt
- missing belt on incomplete engines
- broken belt
- repair of the speed governor
A general service life cannot be stated reliably for historic applications, because age, storage, operating conditions, environmental influences and load can vary greatly. If the existing belt is damaged or no longer present, a suitable replacement belt is required.
Who is this replacement belt particularly relevant for?
The timing belt for the speed governor of the VW Industrial Engine Type 122 is particularly interesting for users who want to preserve older stationary engines or make them operational again.
- Workshops
- Maintenance personnel
- Operators of stationary systems
- Fire departments with historic or existing units
- Agricultural businesses
- Collectors of historic technology
- Restorers
- Technical buyers
How can you check which belt is required?
Anyone looking for a replacement belt for the VW Industrial Engine Type 122 should first check the existing application. The decisive factor is whether it is the belt for the speed governor.
Important checking features are:
- Installation location: speed governor
- Engine type: VW Industrial Engine Type 122
- Width: 10 mm
- Number of teeth: 64
- Reference number: VW122135171A
- Design: timing belt
- Material version: PU with steel tension members
If these specifications match the existing application, the Alphabelt replacement belt may be the suitable solution. If you are still unsure, you are welcome to contact us with your technical data, photos of the existing belt or information about the engine.
Not an original VW part, but an Alphabelt reproduction
This timing belt is not an original Volkswagen part. The terms VW, Volkswagen, VW Industrial Engine Type 122 and the reference number VW122135171A are used exclusively for technical description, identification and assignment.
The belt is manufactured by Alphabelt as a reproduction or replacement belt. This is particularly useful for older technical applications where original parts are no longer available.
Compact. Robust. Proven | Fast delivery | Long service life
FAQ: Frequently Asked Questions About the Timing Belt for VW Industrial Engine Type 122
What is the timing belt used for on the VW Industrial Engine Type 122?
The timing belt drives the speed governor. On the stationary VW Industrial Engine Type 122, this speed governor operates the throttle valve in the carburetor.
What reference number does the timing belt have?
The reference number is VW122135171A. It is used for identification and technical assignment of the suitable replacement belt.
Is the timing belt an original VW part?
No. It is not an original Volkswagen part, but a reproduction or replacement belt manufactured by Alphabelt.
What width is the timing belt?
The timing belt has a width of 10 mm.
How many teeth does the timing belt have?
The timing belt has 64 teeth.
What material is the replacement belt made of?
The replacement belt is made of polyurethane and is equipped with endless steel tension members.
Why is a timing belt without a joint advantageous?
A timing belt without a joint has no seam and no splice. This means no additional structural weak point is created in the belt.
Can the timing belt be ordered online?
Yes, the Alphabelt replacement belt for the speed governor of the VW Industrial Engine Type 122 can be ordered online in the shop.
Conclusion: Suitable Replacement Belt for a Specific Application
The timing belt for the speed governor of the VW Industrial Engine Type 122 is a small but important component. It drives the speed governor, which operates the throttle valve in the carburetor during stationary use.
Since original replacement belts are difficult or no longer available today, Alphabelt offers a suitable reproduction. The belt is 10 mm wide, has 64 teeth, carries the reference number VW122135171A and is manufactured from polyurethane with endless steel tension members.
Do you need a replacement belt?
Check the technical data of your existing belt and compare width, number of teeth and reference number. You can view and order the Alphabelt timing belt for the speed governor of the VW Industrial Engine Type 122 directly in the shop.