REG. CODE
1-5302-528
MODEL N°
50805
DATE OF ISSUE
31.07.2001
REVISION
00
DATE
31.07.2001
ENDORSED
COMPILER TECO/ATL
32
DISASSEMBLY/REASSEMBLY
VIII
Carburetor
Details
1) throttle rod
2) air adjustment screw
3) spring
4) throttle
5) spring
6) screw
7) main jet
8) loat
9) drain valve
10) float chamber
11) gasket
12) floating pin
13) needle valve
14) idle jet
15) choke plate
16) choke plate command rod
CARBURETOR CHARACTERISTICS
for standard engines with dry air filter
engine
carburetor needle main idle
type
type
main jet jet
LGA 280
FHBC25-21
1.5
86 45
LGA 340
FHBC25-21
1.5
88 45
For cleaning and checks, proceed as follows:
- Totally disassemble the carburetor and carefully wash all parts with petrol or diesel fuel. Never use metal points when cleaning the jets
and calibrated channels.
- Check the needle valve seal and sliding movement in the seat. Replace if necessary.
- Check the condition and free movement of the float.
- Check that the throttle rod is free to rotate throughout its field of action, and that there is not excessive clearance between the rod and
the seat allowing air infiltration.
- Check that the choke plate is not worn and that it rotates freely.
LUBRICATION
Lubrication of internal moving parts is by means of oil, taken from an oil dipper fitted on the rod cap, and centrifuged by the rotation of
the crankshaft. Lubrication of the camshaft, tappets, springs and valves is by means of an ascending flow of sprayed oil, in the form of
emulsion and vapor, that is directed from the lower part of the crankcase towards the head through special passages; movement is
forced by the piston movement. The breather pipe maintains the correct pressure inside the engine casing and prevents oil leaking out
and impurities entering. Before starting the engine, make sure that the sump contains the correct type and quality of oil, as indicated at
table page 15.
43
