I started writing a manual for the Pierburg 2B5 / 2B7 carburettor a few years ago but didn't get very far with it. I'm not going to do any more work on it so I'll post up the photos and details I collected at the time. Hopefully someone else will take the baton and finish it? Feel free to post any info/photos/whatever related to this carb in this thread. It is quite possible that there are some errors that need correcting, so please post any corrections.
1 Vehicle Applications
The Pierburg 2B5 carburettor was fitted to the 740 models that had the B230K engine, during the 1985 and 1986 model years. Note that Volvo model years run from October to September. For example, the 1986 model year ran from October 1985 to September 1986. The Pierburg 2B7 carburettor was fitted to the 740 models that had the B230K engine between 1987 and 1990. The B230K engine in this period was known as the 'heron' engine and may sometimes be referred to as a B230KH to differentiate it from the earlier B230K engines. For completeness, a full list of the carburettors fitted to the 740 model is tabulated below. The Swiss variant of the 2B5 had different jet sizes to the 2B5 used elsewhere. Also the 2B7 had slightly different jetting to the 2B5 variants. Some of the differences between the 2B5 and 2B7 are that the 2B5 had a fuel return connection whereas the 2B7 did not. Also, the 2B5 utilised a 2-stage choke pull-down diaphragm whereas the 2B7 utilised a 3-stage choke pull-down diaphragm.
The above tables show the carburetted 740 models. There was also a carburetted version of the 760; the B28A. It used a single SU carburettor (volvo pn: 1269717).
2 Carburettor Specifications
