| # |
SYMPTOM |
TRY /CHECK
If the problem gets better, continue in the same
direction.
If the problem worsens, go in the opposite direction. |
| 1 |
Blackens Spark Plugs while driving |
Smaller main jets, lower float levels,
lower power valve number, reset butterflies. |
| 2 |
Blackens Spark Plugs at Idle |
Reset butterflies, Screw in mixture screws,
lower float levels, lower fuel pressure, clean out air bleeds, use
smaller number power valve,
increase static ignition timing. |
| 3 |
Backfires through carburetor |
Screw out mixture screws, increase squirter
size, raise float levels, reset butterflies, increase main jet size,
check engine timing. |
| 4 |
Backfires through the exhaust |
Screw in mixture screws, decrease squirter
size, lower float levels, reset butterflies, decrease main jet size,
check engine timing. |
| 5 |
Doesn't pull at wide open throttle |
Increase main jet size, raise float levels,
increase fuel pressure |
| 6 |
Float levels wont adjust |
Lower fuel pressure, clean needle and seat
assembly, make sure floats move freely |
| 7 |
Float bowls drain down after shut-off |
Retighten bowl screws and power valve,
replace bowl metering block and power valve gaskets, clean out air
bleeds. |
| 8 |
Fuel drips out of boosters |
Lower float levels, lower fuel pressure,
reset butterflies. |
| 9 |
Fuel drips out of Accel/Pump nozzle |
Loosen tension on accelerator pump arm |
| 10 |
Fuel leaks out Throttle shafts |
Lower float levels, lower fuel pressure,
clean out and/or replace needle and seat assembly, reset butterflies,
clean out air bleeds |
| 11 |
Fuel shoots out Vent Tubes |
Lower float levels, lower fuel pressure,
clean out and/or replace needle and seat assembly, make sure the floats
move freely. |
| 12 |
No adjustment on Mixture screws |
Reset butterflies, increase initial engine
timing, lower float levels and fuel pressure. |
| 13 |
Rich while driving |
Smaller main jets, lower float levels,
smaller power valve, (For very rich check for blown power valve
diaphragm) |
| 14 |
Rich at idle |
Reset butterflies, screw in mixture screws,
lower float levels, lower fuel pressure, clean out air bleeds, use
smaller number power valve, increase initial ign timing |
| 15 |
Runs on after shut-off |
Reset butterflies, lower idle RPM, check
engine timing. |
| 16 |
Vac secondaries do not open |
Install a lighter secondary diaphragm
spring |
| 17 |
Sluggish at wide open throttle |
Decrease main jet size, lower float levels,
lower fuel pressure |
| 18 |
Smells rich at Idle |
Reset butterflies, screw in mixture screws,
lower float levels, lower fuel pressure, clean out air bleeds, use
smaller number power valve,
increase initial ignition timing. |
| 19 |
Smokes at idle |
Reset butterflies, screw in mixture screws,
lower float levels, lower fuel pressure, clean out air bleeds, use
smaller number power valve,
increase initial ignition timing. |
| 20 |
Smokes under acceleration |
Decrease squirter size, lower float levels,
lower fuel pressure, reset butterflies. |
| 21 |
Stumbles or hesitates (Light Acceleration) |
Reset butterflies, raise float levels,
reset mixture screws |
| 22 |
Stumbles or hesitates (Hard Acceleration) |
Increase squirter size, reset butterflies,
raise float levels. |
| 23 |
Surges at idle |
Reset butterflies, screw out mixture
screws, raise float levels. |
| 24 |
Surges at cruise |
Reset butterflies, raise float levels, turn
mixture screws out, install larger main jets, install a higher power
valve number. |
| 25 |
Wont idle down |
Reset butterflies, check mixture screws,
lower float levels, check initial timing, check throttle linkage, check
for vacuum leaks |
| 26 |
Wont stay running below 1500 rpm |
Reset butterflies, check mixture screws,
lower float level, check initial timing |
| 27 |
Wont start |
Prime carb with fuel, pump squirters, check
float level, check ignition timing |
| 28 |
Wont stay running |
Reset butterflies, check mixture screws,
lower float, check initial timing. |
