Carburetor Adjustment - Ford 4000 Series Shop Manual

2000-3000-4000
cover. Converter freezing could be
caused by:
1. Water lines restricted.
2. Internal fuel leak.
3. Low engine coolant level.
4. Defective engine water pump.
5. Loose engine fan belt.
6. Defective hose or fittings.
7. Air lock; remove top water hose
from the converter and bleed
system.
8. Engine head gasket leaking.
CARBURETOR ADJUSTMENT
116. First, adjust slow idle fuel mix-
ture and idle speed as follows: Refer to
Fig. 108 and loosen the drag link lock-
nuts (18L and 18R). With the engine
running and throttle control lever in
slow idle position, adjust idle fuel mix-
ture by rotating the knurled barrel (16)
to lengthen or shorten the drag link.
When smoothest engine idle operation
is obtained, adjust engine idle speed by
turning the idle speed set screw (13-
Fig. 107) in or out to obtain engine slow
idle speed of 600-650 RPM. Then, read-
justdrag link as necessary to obtain
smoothest engine operation at slow idle
speed and tighten the drag link lock-
nuts. Note that one locknut (18L-Fig.
108) has left hand threads and the
other (18R) has right hand threads.
Power (load) adjustment is made by
rotating the spray bar (1-Fig. 107).
The end of the spray bar is marked "R"
for rich and "L" for lean mixture. Ad-
justment must be made with tractor
connected to a PTO dynamometer or
using an exhaust analyzer. When
using dynamometer, rotate spray bar
to obtain maximum horsepower. When
using an exhaust analyzer, rotate
spray bar to obtain a wide open throttle
reading of 14.3 on LP-Gas scale; be
sure to closely follow analyzer oper-
ating instructions. It will not be neces-
sary to readjust idle speed and fuel
mixture as they are not affected by
spray bar adjustment.
R&R AND OVERHAUL
117. CARBURETOR. To remove
the carburetor, disconnect the vapor
hose, air cleaner hose and governor
rod, then unbolt and remove carburetor
from intake manifold.
Prior to disassembling, note position
of throttle lever and drag link assem-
blies; it is possible to reassemble the
carburetor with components reversed.
Exploded view of carburetor in Fig. 107
shows correct assembly; however, unit
is shown upside down. Refer to Fig. 108
for completely exploded view of the
drag link assembly.
Completely disassemble the car-
buretor and clean all parts in a suitable
Paragraphs 116-117
Fig. 106-Exploded view of the LP-Gat system used on model 4000 tractor . Refer to Fig. 109 for
exploded view of filter -fuelock assembly (13); to Fig. 107 for exploded view of carburetor (31) and to
Fig. 110 for exploded view of converter (vaporizer-regulator) (35).
1. Fuel gage
12. 'Tea'
22. Tube
33. Fuel hose
2. Gasket
13. Filterduelock 23. Elbow 34. Elbow
3. Reliefvalve 14. Elbow
24. Tube, water 35. Converter
4. Raincap
16. Tube, fuel 25. Elbow 36. Tube, fuel
6. 80% fill valve 16. "Tee"
26. Adapter
37. Elbow
6. Fueltank
17. Gasket 27. s cers
38. Elbow
7. Supply valve 18. Cap
28. Mounting bracket 39. Tube, water
8. supply valve
19. Liquid-vaporvalve
29.Spacer 40. Connector
9. Tube
20. Vapor return-fill 30. Gaskets 41. Radiator hose
10. Elbow v alve
31. Carburetor 42. Adapter
11. Tube
21. Elbow 32. Fitting
43 Radiator hose
Fig. 107-Exploded view of Century LP-Gas carburetor assembly . View is with unit turned upside
down, and with air horn removed. Refer to Fig . 108 for fully exploded view of drag link assembly.
1. Spray bar
8. Stop pin
15. Clamp screw
22 Washer
2. Throttle shaft
9. Retaining screw
16. Drag link body
23- Metering valve body
3. Throttle disc
10. Metering valve lever 17. Spring 24 Metering valve seal
4. Seal retainer
11. Spring
18. Jam nut
25. Metering valve
5 Shaft seals 12. Ball etude
link end 19. Dr
26. Spring
.
6 Bushings
13. Idle .peed screw
y,
20. Baocket beatings
27. Plug
.
7. Throttle body 14. Throttle lever
21. Metering valve lever 28. Gasket
41