English – 37
Leak in Fault with
Diuser jets Needle valve
Leak in the impulse pipe Pump diaphragm
Ventilation hole above Control diaphragm
metering unit
Fig 44
Pressure testing the carburettor
Pressure testing should be carried out with the
carburettor fully assembled. The test must always
be done after the carburettor has been repaired,
but can also be carried out when troubleshooting
before the carburettor is taken apart.
Test 1
See Figure 44 and carry out the following check:
1. Connect pressure tester to the carburettor fuel
inlet.
2. Lower the carburettor into a beaker of water.
3. Pump up the pressure to 20 kPa.
4. No leakage is permitted. If a leakage occurs
refer to the table below.
Test 2
1. Plug the connections to the fuel inlet.
2. Create a vacuum to the purge nipple on the
carburettor. No leakage is permitted. In the
case of leakage, leakage spray can be used
even it if is dicult. Try and identify where
the spray is sucked in. It can be used to
show leakages in main jets, idling needles,
measuring cover gaskets and measuring
diaphragms.
Repair instructions