On the Volkswagen Beetle up to December 1953 and the single brake system of the Volkswagen Bus, the brake fluid reservoir is screwed directly onto the master cylinder. At the time, this was a perfect solution with the least chance of leakage. That is the reason why this brake system is often used in buggies and all kinds of other home-made creations. The reservoirs for the Volkswagen Beetles between January 1954 and July 1960 are made of metal, where the cap is seen as an extra option, with all the other reservoirs (if applicable) the cap is included.
The later Volkswagen Beetle, Karmann Ghia and VW Thing use a reservoir that is located elsewhere in the car.
In the last production months of the Split Bus the reservoir on the master cylinder was filled directly. With the Baywindow Bus this was no longer possible due to lack of space, the reservoir is refilled by means of a fill-reservoir which is placed elsewhere in the car.
In the third generation Volkswagen Bus, the brake fluid reservoir is again filled directly without the aid of a filler tank. In addition to being a reservoir for the brakesl, it is also the reservoir for the hydraulic clutch.
Note : It is essential that the reservoir is free of leaks, so check it regularly.
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