Note: Use only new gaskets and O-rings when reassembling.
Assembling the carburetor body
1. Assemble the carburetor body with the mixing chamber body (bottom or "flange" carburetor), by installing a new insulator and fixing the body parts to be connected with three screws.
2. Install the sight glass on the new O-ring and secure it with two screws.
3. (version with carburetor without additional shutter in the secondary chamber)
Assemble the secondary throttle actuator by installing the following parts in the order shown in the figures: (1) frame, (2) spring, (3) diaphragm, (4) lid, (5) retainer, (6) cable clamp.
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4. (variant without additional damper in the secondary chamber) Install the secondary throttle actuator.
A) Install the sealing ring.
b) Fasten the drive rod and attach the drive housing to the carburetor body with two screws.
V) Install the return spring.
5. (carburetor option with an additional damper in the secondary chamber)
Install corrector ("compensator") composition of the idle mixture when the engine warms up (HIC), by installing the valve seat and HIC valve and securing the HIC body with two screws.
6. (carburettor version with additional choke in the secondary chamber and with the cam switch of the system for increasing the idle speed (FICB)) Attach linkage and secure cam switch (FICB) two screws.
7. (Carburettors with additional accelerator pump (AAR)) Set aperture (1), spring (2) and cover (3) auxiliary accelerator pump (AAR) and secure with three screws.
8. Install the accelerator pump, fixing the spring with four screws (1), aperture (2), cover (3) and guide (4) (if any).
9. Install the solenoid valve (or valves) shut off the fuel supply using a new gasket and a new o-ring.
10. (variant without additional damper in the secondary chamber) Install the small secondary chamber diffuser by securing it with two screws. along with a new gasket.
11. Install the jets and the economizer valve following the sequence shown in the figure:
A) The main fuel jet of the primary chamber with a new gasket;
b) Channel plug with a new gasket;
V) The main fuel jet of the secondary chamber;
G) (Only for carburetor with additional shutter in the secondary chamber) dosing needle guide;
d) Economizer valve;
e) Idle jet with new O-ring.
12. Install throttle opener or throttle lever (TR).
Assembling the carb cap (float chamber covers)
1. (Carburetor option without secondary choke and with high idle control cam switch (FICB)) Install Idle Speed Cam Switch (FICB).
2. Install the positioner ("switch") air damper (SW).
(Carburetor with automatic choke (option with a double diaphragm in the mechanism of its pneumatic drive))
A) Insert the inner diaphragm into the thermostat housing, install the collar and split circlip.
b) Insert the stem of the inner diaphragm into the hole in the thermostat housing.
V) Connect with three screws: spring (1), frame (2), outer diaphragm (3) and cover (4).
(Carburetor with automatic choke (version with a single diaphragm in the mechanism of its pneumatic drive))
A) Insert the diaphragm into the thermostat housing, install the cuff, spring, and retainer with a split circlip.
b) Insert the diaphragm rod into the hole in the thermostat housing.
V) Fasten the spring with three screws (1) and cover (2).
(Manual choke carburetor)
A) Fasten the choke switch (SW) two screws.
b) Install the choke shaft with spring.
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V) Fix the air damper plate with two screws (pre-apply sealant to the threads of the fastening screws).
3. (Carburetor with automatic choke)
Install the spring housing.
A) Install the gasket and thermostat housing.
b) (Carburetor with high idle control cam switch (FICB))
Align the bimetal spring with the choke lever and install the spring housing.
(Carburetor without idle cam switch (FICB)) Align the bimetal spring with the wire loop and install the spring housing by aligning it with the choke lever as shown.
V) Align the center line of the thermostat housing with the line on the spring housing and secure the housing with three screws.
G) Check the operation of the air damper.
4. (Carburetor with float chamber imbalance valve (OVCV valve))
Install a new gasket and secure the OVCV valve with three screws.
5. Install the economizer piston together with the spring and retainer, securing the retainer with the screw.
6. Install a new gasket and needle valve seat in the carburetor cover receptacle.
7. Install needle valve and float.
Hook the wire tie (loop) needle valve for the float adjusting plate. Then install the float and fix it on the axis.
8. Adjust float level.
Attention: Measurements must be taken without the gasket on the carburettor cap.
A) After installing the cover with the float up, measure the gap between the top of the float and the plane of the cover connector.
- float level (raised position) - 8.2 mm
b) If necessary, adjust the level by bending the float adjusting bar (A).
V) Raise the float and, using a caliper with a depth gauge, check the distance between the cover slot surface and the bottom of the float.
- float level (down position) - 47.1 mm
G) If necessary, adjust by bending the float plate marked with the symbol (IN).
9. Install the carb cap (float chamber cover).
A) Install a new gasket; Install the carburetor cover assembly to the carburetor body.
b) Fix the following parts with five screws: Brackets A (1) and B (2), and number plate (3).
V) Connect the idle speed boost link (4).
G) (Carburetor without secondary choke and with high idle control switch (FICB))
Connect the high idle control cam switch rod (FICB) (5).
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10. Install choke switch vacuum tubes (SW) and switch of the cam of the system for increasing the idle speed (FICB).
A) Install vacuum tubes and pneumatic diode (Pneumatic valve VTV) (1) choke position switch (SW).
b) (Carburetor with high idle control cam switch (FICB))
Install vacuum tubes and fitting (2) cam switch (FICB).
11. (carburetor with an additional damper in the secondary chamber) Install the dosing needle by inserting it into the guide in the carburetor cap and sliding on the spring.
Then install a flat washer and tighten the pinch screw.
12. Install the following parts:
A) (For carburetor with automatic choke) spring bracket;
b) (For 2Y-C engines (U) and 3Y-C (U)) vacuum tubes and vacuum hoses;
V) accelerator return spring;
G) (For engines with vacuum hoses)
Vacuum hoses according to the labels installed during disassembly.
13. Attach the wires to the connectors:
A) (For engines with automatic choke) Spring housing wire;
b) (For motors with float chamber unbalance valve (OVCV valve)) OVCV unbalance valve wire;
V) (For engines with fuel shutoff solenoid valve)
solenoid valve wire (solenoid valves).
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14. Check each moving part of the carburetor for smooth movement / operation.