BA-4 Heater

The gas-electric heater Eberspächer BA4 came as standard equipment on all VW Type 4s. It was necessitated by the simple fact that the old-style heat-exchangers, a design taken over from beetle engines and enlarged, could not handle the passenger compartment size.

The BA4 enables the driver to not only heat up the air coming out of the standard heat exchangers a lot further, it also acts as a stand-alone unit which can be used to pre-heat the passenger compartment, even without the engine running. This is done with a timer built into the main dashboard switch which can be set to run the heater unattended for up to ten minutes.

Volkswagen provided their dealers with a comprehensive workshop manual for the BA4. The register below lists the contents and provides links to jump directly to the Chapter you need.

There are a couple sites on the web that show the same manual, but other people just put the naked scans of each page on the web. The problem here is the file size: There are over 40 page scans, but each single one is between 150 and 250 kilobytes in size. What a nightmare to try and go through on a modem connection. What I did here is use only the pictures and type the text instead of using the scans. Besides, I have the added benefit of a register (see below) to make navigation around the different topics easier.

One interesting side note is the English used in this manual. It is obvious that the manual was translated by a German speaker, as seen by the German sentence structures and expressions which were simply translated word by word. As if a multinational company like Volkswagen cannot get something better than a pretty inept German to translate this important technical manual...

Contents

Description		General overview over the operation of a BA 4 heater, including parts descriptions, maintenance and wiring diagrams.
Troubleshooting		Step-by-step guides for diagnosing and repairing common problems.
Component Testing		Testing procedures for individual components.
Heater and Ducts		Description and removal/installation instructions for the heater body and warm air ducts.
Component Installation		Guide to removing and installing individual heater system components.
Combustion Air Blower		The combustion air blower components and how to tear it apart and repair it.
Fuel Pump		Fuel pump assembly, disassembly and adjustment.