Engine idle speed check (6000 Mile (10 000 Km) / 6 Month Service)
Note: Refer to the precautions given in Section 1 of Chapter 4 before proceeding.
Note: Before carrying out any carburettor adjustments, ensure that the ignition timing and spark plug gaps are set as specified. To carry out this adjustment, an accurate tachometer will be required.
Ford 1V carburettor
1 Ensure that the air cleaner is correctly fitted, and that all vacuum hoses and pipes are securely connected and free from restrictions, then run the engine until it is at normal operating temperature.
2 With the engine at normal operating temperature, adjust the idle speed screw
Ford 1V carburettor idle speed screw (A) and mixture screw (B)
to obtain the specified idle speed, using a tachometer to ensure accuracy.
Ford VV carburettor
3 This procedure must be carried out with the radiator cooling fan in operation. To keep the fan running during the adjustment procedure, disconnect the wiring multi-plug from the thermal switch (located in the thermostat housing) and bridge the two contacts in the plug with a short length of wire.
Temporary bridging wire in cooling fan thermal switch multi-plug
Disconnect the wire and refit the multi-plug on completion of the adjustments. Make sure that the engine and ignition are switched off when connecting and disconnecting the bridging wire.
4 Ensure that the air cleaner is correctly fitted, and that all vacuum hoses and pipes are securely connected and free from restrictions, then run the engine until it is at normal operating temperature.
5 With the engine at normal operating temperature, connect a tachometer in accordance with the manufacturer’s instructions.
6 Start the engine, run it at 3000 rpm for 30 seconds and then let it idle. Turn the idle speed adjusting screw in or out as necessary to bring the speed to that given in the Specifications.
Ford VV carburettor idle speed screw (A) and mixture screw (B)
Weber 2V carburettor
7 Refer to the information relating to the Ford 1V carburettor for details, and to the accompanying illustration
Weber 2V carburettor idle speed screw (A) and mixture screw (B)
for the adjusting screws. Ensure that the engine fan is operating by pulling the two wires from the sensor, and connecting the wires with a jumper lead.
Weber 2V DFTM
8 Before carrying out this adjustment, ensure that the air cleaner is correctly fitted and that all vacuum hoses and pipes are securely connected and free from restrictions. Run the engine until it is at normal operating temperature.
9 The cooling fan must be kept running during the adjustment procedure. To do this, disconnect the wiring multi-plug from the thermal switch (located in the thermostat housing) and bridge the two contacts in the plug with a short length of wire.
10 Start the engine and turn the idle speed adjustment screw
Weber 2V DFTM carburettor mixture screw (A) and idle speed screw (B)
to obtain the specified idle speed, using a tachometer to ensure accuracy.
Weber 2V TLD carburettor
11 Refer to the information relating to the Weber 2V DFTM carburettor for details, and to the accompanying illustration
Weber 2V TLD carburettor mixture screw (A) and idle speed screw (B)
for the adjusting screws.
Weber (1V) TLM carburettor
12 Before carrying out this adjustment, ensure that the air cleaner is correctly fitted and that all vacuum hoses and pipes are securely connected and free from restrictions. Run the engine until it is at normal operating temperature.
13 Connect a reliable tachometer to the engine in accordance with the manufacturer’s instructions.
14 Increase the engine speed to 3000 rpm and hold it at this speed for 30 seconds, then allow the engine to idle. Adjust the idle speed to within the specified range by turning the idle speed screw.
Weber (1V) TLM carburettor idle speed screw (A) and mixture screw (B)