Triumph TR6 PI Operation Manual page 181

FUEL SYSTEM - TC
EMISSION CARBURETIER - FAULT DIAGNOSIS
NOTE: Before undertaking extensive carburetter servicing it is recommended that other engine factors and components such
as cylinder compressions, valve clearance, distributor, sparking plugs, air intake temperature control system, etc., are checked
for correctness of operation.
SYMPTOM
1. Poor idle quality
a.
b.
c.
d.
e.
CAUSE
Air leakage on induction
manifold joints.
Throttles not synchronized.
Air valve or valves sticking in
piston guide-rods.
Partially or fully obstructed
float-chamber or diaphragm
ventilation holes.
Incorrect fuel level caused by
maladjusted float assemblies or
worn or dirty needle valve.
ACTION
Remake joints as necessary. Check idle
carbon monoxide level with CO meter.
Re-balance carburetters and re-set
linkage.
Clean air valve rods and guides and
reassem ble. Check piston free
movement by hand· unit should move
freely and retun to carburetter bridge
with an audible click.
Check that gasket(s) are not causing
obstruction or piping obstructed.
Reset float heights and clean or
replace needle valves worn.
f
Metering needle incorrectly
fitted or wrong type of needle
fitted.
g.
Diaphragm incorrectly located
or damaged.
h. . Leakage from ignition retard
unit pipe connections.
Ensure shoulder of needle is flush with
face of air valve and that needle bias is
correct.
Check location with air valve cover
removed, piston depression holes
should be in line with and face
towards the throttle spindle. Renew
diaphragm with correct type if damage
is in evidence.
Re-make connections and re-check
ignition settings.
i.
Temperature compensator
faulty.
With engine and carburetter cold,
check that compensator cone is seated,
and free to move off seat, If any doubt
exists, replace unit with new assembly.
I9.00.0IC
j.
After
leakage
spindle
spindles
considerable service
may occur at throttle
or secondary throttle
Replace spindle seals or spindles as
required.
continued
Triumph TR6 ManuaL Part No. 545277 Issue I