H Type Carburetter Dismantling

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H Type Carburetter: Dismantling


1. Banjo Bolt
2. Banjo Union
3. Fibre Washers
4. Filter Assembly
5. Marks for Replacement
6. Damper
7. Washer for Damper
8. Suction Chamber Retaining Screws
9. Suction Chamber
10. Direction of Removal


(a) Thoroughly clean the outside of the carburetter.
(b) Remove the banjo bolt, banjo union and fibre washers.
(c) Extract the filter and spring assembly from inside the inlet of the float chamber lid.
(d) Mark the relative positions of the suction chamber and the body.
(e) Remove the damper and its washer. Unscrew the chamber retaining screws.
(f) Lift off the chamber without tilting it.


1. Piston Spring
2. Alternative Spring and Washer
3. Piston Assembly
4. Needle Locking Screw
5. Needle


(a) Remove the piston spring and washer (when fitted).
(b) Carefully lift out the piston assembly and empty the damper oil from the piston rod.
(c) Remove the needle locking screw and the needle. If the needle cannot be easily removed, first tap it inwards and then pull it out, do not bend it.



(a) Unhook the lever return spring. Remove the split pins and clevis pins.
(b) Remove the fast-idle cam pivot bolt. Note the positions of the double-coil spring washer and the aluminium spacing washer.
(c) Detach the linkage assembly.
(d) Press up the piston lifting pin, extract the circlip from its groove and withdraw the pin and its spring downwards.


(a) Withdraw the jet downwards.
(b) Detach the jet adjusting nut and spring.
(c) Unscrew the jet locking nut and withdraw the assembly carefully.
(d) Lift off the upper jet bearing and copper washer. From inside the bearing extract the gland and brass gland washer
(e) Remove the gland spring and withdraw the lower jet bearing from the jet locking nut. Note the brass washer under the shoulder of the bearing. Extract the gland and brass gland washer from inside the bearing. Do not disturb the jet locking nut cork washer.



(a) Remove the screw retaining the stay to the carburetter body (when fitted). Remove the bolt or nut retaining the float-chamber to the body. Note the positions of the three fibre washers and the brass washer, or alternatively, the position of the rubber grommets and steel washers.
(b) Mark the relative position of the float chamber and lid. Unscrew the central nut and remove the drain pipe and washers; the stay, washer and cover cap, or the cover cap alone, as is fitted to the individual carburetter. Note the relative positions of the washers and other components. Lift off the lid, noting the gasket between the lid and the chamber
(c) Invert the float-chamber to remove the float.


(a) Push out the hinge pin of the hinged lever from the end opposite to its serrations and detach the lever.
(b) Lift out the needle from its seating and unscrew the seating from the lid using a box spanner 8.58 mm (0.338 in) across the flats. Take great care not to distort the seating.


(a) Slacken the spring clip bolt and remove the clip, spring, and return spring plate (when fitted). If a clamp-type operating lever is fitted, slacken the clamping bolt and remove the lever.
(b) Close the throttle and mark the position of the throttle disc.
(c) Unscrew the two disc retaining screws.
(d) Open the throttle and ease out the disc from its slot in the throttle spindle. The disc is oval and will jam if not withdrawn carefully.
(e) Withdraw the spindle from the carburetter body

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