Diagnostics
Before starting carburetor maintenance, it is advisable to check the adjustments on the road or on a road simulator. Information on the selection of exhaust components can be found on the engine compartment wall.
2. Problems with the carburetor usually manifest themselves in difficult starting, sluggish acceleration, backfires, fuel overflow, etc. Particular attention is required for a carburetor with traces of fuel leaks and/or coke deposits.
3. Some faults may be caused by fuel leaks, engine malfunction or electrical components. A fairly complete diagnostic procedure is as follows:
- a) Check vacuum hoses for leaks and proper installation.
- b) Check the reliability of the carburetor-collector and collector-head joints. Tighten the fasteners.
- c) Check the compression value in the cylinder (see Chapter 2).
- d) Clean or replace spark plugs (see Chapter 1).
- d) Check the spark plug high-voltage wires (see Chapter 1).
- e) Check the low voltage circuit of the ignition coil.
- g) Check the ignition timing angle (the adjustment instructions are located on the wall of the engine compartment)
- c) Check the operation of the fuel pump (see Chapter 4).
- i) Check the operation of the "heat/cold" flap in the air filter housing (see Chapter 1).
- k) Replace the air filter element (see Chapter 1).
- l) Check the operation of the crankcase ventilation valve (see Chapter 6)
- m) Replace the fuel filter (see Chapter 1).
- n) Check the resistance of the exhaust system.
- o) Check the operation of the exhaust gas recirculation valve (see Chapter 6).
- p) Check the position of the air damper - it should be fully open on a warm engine (see Chapter 1).
- p) Check for fuel leaks in the pipes, absence of resistance in the form of bends or dents.
- c) Check the operation of the accelerator pump with the engine off: when you press the pedal, you should see a tray of gasoline from the sprayer.
- t) Check the quality of gasoline.
- y) Check the valve clearances and the camshaft cam height (see Chapter 2).
- f) At the service station, carry out diagnostics of the electronic engine and carburetor control.
4. Caution: When diagnosing the carburetor, the air filter is often removed. In this case, burns from backfire flames are possible, take precautions. Repair.
5. If you decide that the carburetor requires repair, this can be done in several ways. If you are going to repair the carburetor yourself, purchase the necessary spare parts, including gaskets. You will also need a special solvent and compressed air to clean the internal passages (see figure 9.5).
6. Alternative repair consists of replacing the carburetor. Replaced only with an identical model.
8. Since carburetors are continually being improved to meet increasing emissions requirements, it is impossible to provide step-by-step repair instructions for all types.
(Publication reprinted from the website «www.hondabook.ru»)