MINSK Repair Manual page 24

sound. Dirty petrol often gathers around this washer seal on the stopping pin
causing the carburettor to overflow – therefore make sure it is clean.
Check that the overflow hole on the bottom cup of the carburettor is not
blocked as then any excess petrol will not be able to get out, which will make the
bike harder to start.
If you want to perform a thorough clean then remove the float tanks, the
blocking pin (don't loose the tiny washer seal on the pin) and the two jets – the
longer one is for normal acceleration while the smaller one is for when the engine
is running on idle (the same applies for the round version however the idle jet can
not be removed as it is recessed into the metal. Put all the bits into a metal tray and
give them all a good clean with petrol and an air blower. Essentially you are
making sure that all the little holes and tubes in the carburettor and bits are not
blocked up. Don't use anything plastic like a toothbrush to clean the bits as plastic
melts when exposed to petrol. When reassembling the rectangular
carburettor don't forget to put the small black 'U' shaped washer under the
idle jet – the shorter of the two brass coloured jets – and make sure that the
stopping pin has the tiny washer seal on it. The last thing you do before screwing
the carburettor back up again is to put the float tank and stopping pin back on.
This is a finicky little process which takes some nimble hand-work. Again, make
sure that the float can move freely up and down and make sure that when the float
#13 nut
idle screw
#13 nut
petrol button
is in its top most position that the stopping pin actually blocks the petrol from
coming in.
Before you put the carburettor back together again, douse it with petrol – don't
forget the top – and make sure it is clean of any residue from dirty hands.
©Digby Greenhalgh 2000
Minsk Repair Manual
Square Carburettor Top View
21
choke stick
accelerator cable
enters here
air mix screw
petrol tube
connects here