Baywindow Bus Brake Servo Installation Bundle Kit

These 1/4″ NPT to 1/2″ barbed hose fittings are designed for use on aircooled Volkswagen engines where smaller threaded ports need to be adapted to larger 1/2″ breather or oil hoses. Common applications include oil filler breather outlets and Maxi oil pump fittings, making them an essential component in both standard and performance engine builds.

Each fitting features a 1/4″ NPT tapered thread, allowing it to screw securely into oil filler necks, breather boxes, or Maxi oil pump outlets. The tapered thread ensures a tight, leak-resistant seal when installed with suitable thread sealant. On the hose side, the 1/2″ barb provides a strong and secure connection for breather or oil hose, preventing disconnection under pressure or crankcase ventilation flow.

These fittings are particularly important in crankcase breather systems. As engine pressure builds inside the crankcase, gases must be vented efficiently to prevent oil leaks and maintain engine health. These fittings allow larger diameter breather hoses to be connected to smaller threaded outlets, improving airflow and reducing internal pressure. They are also commonly used on Maxi oil pumps where auxiliary outlets require connection to external oil lines.

For installation, you may also require 1/2″ breather or oil hose, hose clamps, and thread sealant. Depending on your setup, these may be used alongside breather boxes, oil catch tanks, or external oil system components.

Sold separately, these fittings provide a reliable solution for both breather and oil system connections.

Vehicle Fitment

Aircooled VW:

• Beetle (1949–1979) – All engines
• Beetle Cabriolet (1949–1979)
• T2 Split Bus (1950–1967)
• T2 Bay Window (1968–1979)
• T25 / T3 Aircooled (1979–1983)
• Karmann Ghia (1955–1974)
• Type 3 (1961–1973)
• Trekker (1968–1983)
• Buggy / Baja (Type 1 based, 1949–1979)

Watercooled VW:

• T25 / T3 Watercooled (1983–1992) – when fitted with custom breather or oil systems

Key Features

• 1/4″ NPT male thread (tapered for secure sealing)
• 1/2″ hose barb for breather or oil hose connection
• Ideal for oil filler breather outlets and Maxi oil pump fittings
• Improves crankcase ventilation when used with larger hoses
• Suitable for performance and upgraded oil systems
• Durable, leak-resistant construction
• Supplied Separately (1 fitting)

13mm Internal Diameter Rubber Oil Hose, sold by the meter.

Suitable for both oil + oil breather hose.

Uses a universal 12mm – 22mm clip sold separately, part number: HOSECLIP1222

Replacement reproduction brake master cylinder for VW Baywindow Buses from 1971 to 1979 fitted with servo-assisted brakes. This dual circuit master cylinder is designed to restore safe, reliable braking performance on late Baywindow models.

The master cylinder is the heart of the hydraulic braking system, converting brake pedal movement into hydraulic pressure which operates the wheel cylinders or brake calipers. Over time internal seals can wear or fail, causing fluid leaks, sinking pedals, poor braking performance, or brake fluid bypass issues. Replacing a worn master cylinder is essential for maintaining safe braking operation.

This reproduction unit is manufactured primarily for left hand drive models, however it can also be fitted to right hand drive buses by modifying and rerouting the brake pipes to suit the port layout.

Important Fitting Notes

• Brake light switch not included
• Compatible brake switches:
  • 2 terminal switch: 113945515H
  • 3 terminal switch: 113945515G
• Some brake pipes may require rerouting due to different port positioning
• Brake switches must sit below the master cylinder centreline to prevent trapped air during bleeding
• Brake pedal pushrod end play must be adjusted to factory specification of 1mm
• Pushrod length may require trimming on some applications

Specifications

• Quality: Reproduction
• System: Dual circuit servo brake system
• Outlets: 4
• Reservoir centres: 85mm
• Application: Servo-assisted braking systems

Recommended Additional Parts

• Brake fluid reservoir seals
• Brake fluid reservoir hoses
• Brake light switches
• Brake pipe unions or replacement brake lines
• Brake fluid
• Servo vacuum hose and seals

To Fit

Aircooled VW

• VW Baywindow Bus – 1971–1979
  • Servo brake models

Top quality black satin plated (high salt resistance) replacement master cylinder pushrod for use on all VW Baywindow buses with servo assisted brakes. 

Quality: Top quality 

Fitting: Supplied with lock nut, clevis pin and safety locking clip

Applications:

VW Baywindow Van: 1972 – 1979

This brake fluid lower reservoir is a top-quality reproduction designed specifically for VW Baywindow Buses from 1973 to 1979 that are equipped with servo-assisted brakes. Mounted directly on top of the brake master cylinder, this reservoir serves as the lower fluid supply container, receiving fluid from the upper reservoir via connecting hoses and delivering it to the braking system.

The unit features twin outlet pipes spaced 85mm apart, designed to push-fit directly into the top of the master cylinder—making it an essential component in the dual-circuit brake system found in late Baywindow models with brake servos. A proper-fitting and leak-free reservoir is crucial to maintaining reliable braking performance and preventing fluid loss or air ingress into the system.

If your original reservoir is cracked, stained, brittle, or leaking, this replacement offers a clean, secure, and OE-style fit, ensuring optimal brake fluid management and long-term durability.

Applications:

• VW Baywindow Van: 1973–1979 (with servo-assisted brakes)

Elevate the safety and reliability of your vehicle`s braking system with the One-Way Non-Return Valve, meticulously engineered for vehicles equipped with a brake servo.

Whether you`re driving a Baywindow, Type 25 (T3) bus, or an aftermarket conversion on Splitscreen buses, this essential component ensures optimal brake performance and peace of mind on every journey.

Originally designed to meet the rigorous demands of automotive engineering, this valve boasts a legacy of excellence that spans generations.

From its inception as a crucial component in the braking systems of iconic vehicles like the Mk1 Golf, to its continued use in modern aftermarket conversions, this valve has stood the test of time, earning the trust of drivers around the world.

Featuring a 13mm inner diameter hose compatibility, this valve seamlessly integrates into your vehicle`s braking system, providing a reliable barrier against backflow and ensuring consistent brake pressure under all driving conditions.

Whether you`re navigating city streets or embarking on epic road trips, you can trust in the precision engineering of this valve to deliver responsive braking performance when you need it most.

But its benefits extend beyond mere functionality.

Engineered to the highest standards of quality and durability, this valve is built to withstand the rigors of daily driving and the challenges of varied road conditions.

Its robust construction ensures long lasting reliability, giving you the confidence to tackle any adventure with peace of mind.

Installation is a breeze, requiring minimal time and effort to achieve maximum results.

With its straightforward design and universal compatibility, this valve is the perfect choice for drivers looking to enhance the safety and performance of their vehicle`s braking system without the need for complicated modifications.

So why compromise on safety or reliability?

Upgrade to the One-Way Non-Return Valve today and experience the difference that precision engineering can make in your driving experience.

Trust in quality, trust in reliability – trust in this valve.

Features easy installation with hex socket or Screwdriver. Clamps are not affected by hot fuels or engine oils and will not rust or corrode.

Sold Separately.

Suitable for any hose with an external diameter between 12 and 22mm.

This Brake servo was designed to fit the new Brazilian Baywindow Buses.  It can of course be used on any Baywindow with a little bit of modification by fitting one of our Universal beam brackets, part number 211612103GBRACKET, see related products.