6M -58 E N G IN E FU E L
ROCHESTER CARBURETOR DIAGNOSIS
ALL MODELS 4 M , 4 M V - FOUR BARREL
P hi
E N G I N E C R A N K S ( T U R N S O V E R ) W I L L N O T
r ro D ie m :
S T A R T 0
r
s t a r t s
h a r d
w h e n
c o l d
POSSIBLE CAUSE
CORRECTIVE ACTION
Improper starting procedure used.
Check w ith the customer to determine if proper starting
procedure is used, as outlined in the owner's manual.
No fuel in gas tank.
Add fuel. Check fuel gauge for proper operation.
Choke valve not closing sufficiently when cold.
Adjust the choke thermostatic coil. Use procedure G.
Choke valve or linkage binding or sticking.
Realign the choke valve or linkage as necessary. If caused
by d irt and gum, clean w ith automatic choke cleaner.
Do not oil choke linkage.
If parts are replaced, check adjustments using procedures
C, D, and E.
Vacuum leaks in carburetor base or intake manifold.
Check all manifold vacuum hoses fo r being connected and
in proper location. Check manifold and carburetor base
gaskets for leaks. Tighten or replace as necessary. Torque
carburetor to manifold nuts 10-14 ft. lbs.
No fuel in carburetor.
1. Remove fuel line at carburetor. Connect hose to fuel
line and run into metal container.
Remove the high
tension coil wire from center tower on distributor cap
and ground. Crank over engine - if there is no fuel dis
charge from the fuel line, check for kinked or bent lines.
Disconnect fuel line at tank and blow out w ith air hose,
reconnect line and check again fo r fuel discharge.
If
none, replace fuel pump.
Check pump for adequate
flow as outlined in service manual.
2. If fuel supply is o.k., check the following.
a. Inspect fuel filters. If plugged, replace.
b. If filters are o.k., remove air horn and check for a
bind in the float mechanism or a sticking float needle.
If o.k., adjust float as specified. Use procedure A.
Engine flooded.
NOTE:
To check for flooding, remove air cleaner w ith
engine o ff, and look into carburetor bores. Fuel w ill be
dripping o ff discharge nozzles and carburetor bores w ill be
very wet.
1. Check to determine if customer is using proper carbu
retor unloading procedure. Depress the accelerator to
the floor and check carburetor to determine if the choke
valve is opening.
If not, adjust th ro ttle linkage and
unloader as specified. Use procedure F.
2. If choke unloader is working properly - check for
carburetor flooding.
NOTE:
Before removing the carburetor air horn, use
the following procedure which may eliminate the flood
ing.
Remove the fuel line at carburetor and plug. Start and
run the engine until the fuel bowl runs dry. Turn o ff
engine and connect fuel line.
Then restart and run
engine. This w ill usually flush d irt past the carburetor
float needle and seat.
3. If d irt is in the fuel system, clean the system and re
place fuel filters as necessary. If excessive d irt is found,
remove the carburetor unit. Disassemble and clean.
4. Check float needle and seat for proper seal. If a needle
and seat tester is not available, apply mouth suction
needle seat w ith needle installed. If needle and seat is
defective, replace w ith factory matched set.
1
LIGHT DUTY TRUCK SERVICE MANUAL
Summary of Contents for Light Duty Truck 1973
Page 1: ......
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Page 53: ...HEATER AND AIR CONDITIONING 1A 27 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 115: ...LIGHT DUTY TRUCK SERVICE M A N U A L HEATER AND AIR CONDITIONING 1A 89...
Page 123: ...BODY 1B 3 Fig 6 Typical 06 Van LIGHT DUTY TRUCK SERVICE MANUAL...
Page 149: ...BODY 1B 29 Fig 84 Body Mounting 06 Fig 85 Body Mounting 14 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 171: ...LIGHT DUTY TRUCK SERVICE M A N U A L Fig 2 Frame Horizontal Checking Typical FRAME 2 3...
Page 173: ...LIGHT DUTY TRUCK SERVICE M A N U A L Fig 4 10 30 Series Truck Frame FRAME 2 5...
Page 174: ...2 6 FRAME LIGHT DUTY TRUCK SERVICE MANUAL Fig 5 Underbody Reference Points G Van...
Page 185: ...FRONT SUSPENSION 3 11 Fig 16 Toe out on Turns LIGHT DUTY TRUCK SERVICE MANUAL...
Page 224: ......
Page 266: ......
Page 351: ...ENGINE 6 15 Fig ID Sectional View of Eight Cylinder Engine LIGHT DUTY TRUCK SERVICE MANUAL...
Page 375: ...EN G IN E 6 39 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 376: ...6 4 0 ENGINE LIGHT DUTY TRUCK SERVICE MANUAL...
Page 377: ...ENG IN E 6 41 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 378: ...LIGHT DUTY TRUCK SERVICE MANUAL Fig 37L K Series Engine Front Mount 6 42 ENG INE...
Page 400: ...6 6 4 ENG INE LIGHT DUTY TRUCK SERVICE MANUAL...
Page 401: ...ENG IN E 6 65 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 402: ...6 6 6 ENGINE LIGHT DUTY TRUCK SERVICE MANUAL...
Page 403: ...E NG IN E 6 67 Fig 36V C Series Engine Mounts LIGHT DUTY TRUCK SERVICE MANUAL...
Page 410: ......
Page 423: ...EN G IN E C OOLING 6K 13 Fig 16 Overheating Chart LIGHT DUTY TRUCK SERVICE MANUAL...
Page 424: ...6 K 1 4 ENG INE COOLING Fig 17 Coolant Loss Chart LIGHT DUTY TRUCK SERVICE MANUAL...
Page 456: ...6M 32 ENGINE FUEL Fig K15 Accelerator Controls G Van L 6 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 492: ......
Page 512: ...Fig 18e Vacuum Advance Diagram V8 Engine...
Page 516: ...6 T 2 4 E M IS S IO N CONTROL SYSTEMS LIGHT DUTY TRUCK SERVICE MANUAL...
Page 528: ......
Page 590: ......
Page 593: ...CLUTCHES MANUAL TRANSMISSIONS 7M 3 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 598: ...7M 8 CLUTCHES MANUAL TRANSMISSIONS LIGHT DUTY TRUCK SERVICE MANUAL...
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Page 743: ...FUEL TANKS AND EXHAUST 8 13 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 744: ...8 14 FUEL TANKS AND EXHAUST LIGHT DUTY TRUCK SERVICE MANUAL...
Page 760: ...8 30 FUEL TANKS AND EXHAUST Fig 40 Exhaust Pipe P Models LIGHT DUTY TRUCK SERVICE MANUAL...
Page 761: ...FUEL TANKS AND EXHAUST 8 31 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 763: ...FUEL TANKS AND EXHAUST 8 33 LIGHT DUTY TRUCK SERVICE MANUAL...
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Page 832: ...LIGHT DUTY TRUCK SERVICE MANUAL Fig 106 Power Steering Pump Mounting Typical 9 66 STEERING...
Page 833: ...PUMP ASSEMBLY STEERING GEAR TYPICAL SMALL V8 TYPICAL LARGE V8 STEERING 9 67...
Page 861: ...STEERING 9 95 Fig 134 Power Steering Pump Leakage LIGHT DUTY TRUCK SERVICE MANUAL...
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Page 886: ...11 10 CHASSIS SHEET METAL LIGHT DUTY TRUCK SERVICE MANUAL...
Page 891: ...ELECTRICAL BODY AND CHASSIS 12 5 LIGHT DUTY TRUCK SERVICE MANUAL...
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