Solex 4A1
The Solex 4A1 is a double register carburetor with automatic start from the manufacturer Solex . In this type of carburetor, two register carburetors are housed in one housing. The type designation stands for 4 throttle valves, construction principle A , version 1 .
Structure and functionality
A 4A1 carburetor is essentially composed of four components: the carburetor cover, the housing, the throttle valve part and the starter device. Since the carburetor is a double register carburetor, it has two carburetor stages each, i.e. four intake pipes and four throttle valves. From idling to about medium load, only the throttle valves of the first two carburetor stages are opened; at full load the throttle valves of the two second stages also open.
Due to mechanical components such as springs, register levers, etc. lying unprotected in the free wind, these types had a tendency to ice up in cold, wet weather with temperatures below freezing point . For example, when driving on the motorway for long periods in sleet, this could mean that the gas could no longer be taken back, but instead had to coast the vehicle at high speed with the engine disengaged and switch off the engine. After a few minutes of standstill, the icing of the mechanics was defrosted again by the engine heat and the journey could be continued.
4A1 carburetor
Carburetor from above
Carburetor bottom
Right carburetor
history
These carburettors were installed in various types of vehicles from several manufacturers in the 1970s and 1980s, mainly in heavy touring sedans with six-cylinder engines . Among other things, they were at BMW (e.g. BMW E21 (model 320), BMW E12 (models 520, 525, 528)) and Mercedes-Benz series W 114 (280, 280C), W 116 (model 280S) as well W 123 (models 250, 280) as well as in the Opel Commodore and the Opel Senator .
Technical specifications
| Parameters | Solex 4A1 (BMW E12 525) |
|---|---|
| Fan diameter | 20/54 mm |
| Main jet stage I | X97.5 |
| Nozzle needle | B5 |
| Air correction nozzle level I / II | 2.1 H7 / 3.7 H7 |
| Idle jet | 42.5 |
| Idle jet | 120 |
| Idle shut-off valve | PE20273 |
| Injection quantity per stroke | 0.6 ± 0.15 cm 3 |
| TN starter gap dimension | 2.1 ± 0.1 mm (at 22 ° C) |
| Idle speed | 900 ± 50 min −1 |
| CO content | <1.5% by volume |
| receipt |
Web links
- Private website with data on use in BMW engines
- Private website with data on use in Mercedes engines
Individual evidence
- ↑ Hans-Rüdiger Etzold: This is how it's done (Volume 68): BMW 5 Series 9/72 to 7/81 (TYPE E12), BMW 5 Series 7/81 to 8/87 (TYPE E28) , Delius Klasing, Bielefeld 1990, ISBN 978-3-7688-0666-4 , p. 105
- ↑ Hans-Rüdiger Etzold: This is how it's done (Volume 68): BMW 5 Series 9/72 to 7/81 (TYPE E12), BMW 5 Series 7/81 to 8/87 (TYPE E28) , Delius Klasing, Bielefeld 1990, ISBN 978-3-7688-0666-4 , p. 108