Contents: Disassembly ↓ Assembly ↓
Disassembly
Remove the return spring 8 (see fig. 40) a lever that limits the opening of the second chamber throttle valve.
Remove the cotter pin and disconnect the rod connecting the three-arm lever 3 to the throttle shaft lever.
Release the pneumatic drive rod 9 from the second chamber throttle drive lever.
Compress the spring of the telescopic rod 4 and separate it from the three-arm lever 3.
Remove the screws and detach the cover with the gasket from the carburetor body, being careful not to damage the float and gasket.
Unscrew the mounting screws and disconnect the throttle body from the carburetor body.
Carefully remove the thermal insulation pad.
Disassemble cover 10 (Fig. 49) of the carburetor, for which:
- using a mandrel, carefully push the float axis 16 out of the posts (push towards the rack with a cut);
- carefully remove float 17 with needle valve 75, gasket 11;
- unscrew the seat 14 of the needle valve, remove the gasket 18;
- unscrew plug 13 and remove fuel filter 12;
- disconnect the telescopic rod 7 and the rod 19 of the starting device from the lever of the axis 8 of the air damper;
- unscrew the fastening screws, separate the air damper 9 and the axle 8.
- unscrew the two screws securing the housing 6 of the starting device and remove it;
- unscrew the three screws securing cover 2 of the starting device, remove the cover with the adjusting screw 1 and spring 3, and then diaphragm 4 with rod 5.
Disassemble the carburetor body, for which:
- unscrew the screw securing the three-arm lever 24 (Fig. 50) for controlling the air damper;
- remove bracket 26, lever 24 and spring 23;
- disconnect rod 25 from lever;
- unscrew the screws of the cover 21 of the accelerator pump, remove the cover with the lever and the diaphragm 20 with the return spring 19;
- unscrew the main air jets 10 and 12, turn the housing over and, lightly tapping it, shake out the emulsion tubes 11 and 13 from the wells;
- unscrew the housings 6 and 18 of the fuel jets of the transition system and the idle system and remove them together with the jets 5 and 17;
- unscrew the valve screw 9, remove the accelerator pump sprayer 8 with gaskets, unscrew the adjusting screw 16;
- remove small diffusers 7 and 22, unscrew main fuel jets 14 and 15, screws securing housing 2 of the pneumatic drive of the second chamber throttle valve and remove it;
- unscrew the three screws of cover 4 and remove it, then remove the spring and diaphragm 3 with rod 1.
Disassemble the 8 throttle valve housing (Fig. 51), for which:
- remove the limiting bushings 13, unscrew the idle speed adjustment screw 14 with the sealing ring 15;
- unscrew the screws securing the cover 18 of the forced idle economizer and remove the bracket 23 with the microswitch 24, the cover 18 with the adjusting screw 19 of the mixture quantity, the housing 77 assembled with the diaphragm 20 and the needle 21 of the economizer and the gasket 16;
- remove seat 22 of economizer needle with puller 67.7801.9520;
- bend back the tab of the lock washer and unscrew the nut securing the levers to the first chamber throttle shaft;
- remove the lock washer, levers 1, 2, 4 and 27 with washers and bushing 3 from the valve shaft, and then the pressure spring 26 of the valve and the valve 25 of the crankcase ventilation;
- after unscrewing the fastening screws, remove the valve 11, the axis 12 and the spring 9 of the first mixing chamber;
- unscrew the nut securing the levers on the second chamber throttle shaft and remove levers 5 and 7 with spring 6;
- remove valve 77 and axle 10 of the second mixing chamber.
Assembly
Assemble the carburetor in the reverse order. The float should not touch the walls of the carburetor, but should rotate freely on the axis. The needle valve should slide freely in its seat. In order not to mix up the jets, pay attention to their markings. After assembling the housing, adjust the fuel level in the float chamber. When adjusting, make sure that the needle valve pull-off fork does not interfere with the free movement of the float.