General information and precautions

Fuel and exhaust systems - carburettor models / General information and precautions

General information
The fuel system comprises a rear-mounted fuel tank, a mechanical diaphragm fuel pump and a downdraught carburettor.

The pump on 1.05 and 1.3 litre models is operated by means of a plunger activated by the camshaft, whilst on 1.6 and 1.8 litre models, it is operated directly by an eccentric on the intermediate shaft.

The air cleaner unit contains a renewable paper element and incorporates an automatic temperature control.

A conventional exhaust system is used on all models, being fitted in sections for ease of replacement.

Precautions
Fuel warning
Many of the procedures in this Chapter require the removal of fuel lines and connections which may result in some fuel spillage.

Before carrying out any operation on the fuel system refer to the precautions given in Safety first! at the beginning of this Manual and follow them implicitly. Petrol is a highly dangerous and volatile liquid and the precautions necessary when handling it cannot be overstressed.

Tamperproof adjustment screws Certain adjustment points in the fuel system are protected by “tamperproof” caps, plugs or seals. The purpose of such tamperproofing is to discourage, and to detect, adjustment by unqualified operators.

In some EEC countries (though not in the UK), it is an offence to drive a vehicle with missing or broken tamperproof seals. Before disturbing a seal, satisfy yourself that you will not be breaking any anti-pollution regulations by doing so. Fit a new seal when adjustment is complete, if this is required by law.

Do not break tamperproof seals on a vehicle which is still under warranty.

Unleaded petrol - usage
For full information on the use of unleaded petrol, consult your VW dealer who will be able to inform you if your vehicle is capable of running on unleaded fuel and, where possible, of the necessary adjustments required. The use of unleaded fuel in a vehicle not designed, or suitably adjusted, to run on unleaded fuel will lead to serious damage of the valve seats.