F624061 Force CARBURETOR COMPLETE, BOTTOM (WE-5-2)

Index
1. Engine Fails to Start2. Misfiring3. Stalls at Low Speed4. Erratic Engine Speed5. Low Power6. Excessive Vibration7. Heavy Combustion Knock8. Valve Train Clicking Noise9. Oil in Coolant10. Mechanical Knock11. Excessive Fuel Consumption12. Loud Valve Train Noise13. Little Rocker Arm Movement and Excessive Valve Lash14. Valve Rotocoil Spring Retainer Free15. Slobber16. Valve Lash Close-up17. Premature Engine Wear18. Coolant in Engine Lubricating Oil19. Excessive Black or Gray Smoke20. Excessive White or Blue Smoke21. Low Engine Oil Pressure22. High Lubricating Oil Consumption23. Abnormal Engine Coolant Temperature24. Starting Motor Fails to Crank25. Alternator or Generator Fails to Charge26. Alternator or Generator Charging Rate Low or Unsteady27. Alternator or Generator Charging Rate High28. Noisy Alternator or Generator Air Induction And Exhaust System
Restriction Of Air Inlet And Exhaust
Engine horsepower and efficiency will be reduced if either the air inlet or exhaust system becomes restricted. The air cleaner should not restrict air flow to the point of 30" (762 mm) of water difference in pressure.Exhaust back pressure (pressure difference measured between the turbocharger outlet elbow tap and the ambient air) should be no more than 27" (686 mm) of water.Measuring Inlet Manifold Pressure
This test should be used if engine horsepower seems to be too low, yet no specific symptom of engine trouble is apparent.Inlet manifold pressures in the RACK SETTING INFORMATION are recorded under specific operating conditions: 29.4 inches (746,76 mm) of mercury barometric pressure, 85° F. (29.4° C.) ambient temperature and 35 API rated fuel. Any deviation from these conditions can affect the inlet manifold pressure. Ambient air which is denser than that at 85° F./29.4 inches (29.4° C/746,76 mm) of mercury, can cause a slightly higher horsepower and inlet manifold pressure rating can be slightly lower than the values given in the RACK SETTING INFORMATION. Fuel density (API gravity rating) also affects the horsepower and inlet manifold pressure. If the fuel is rated above the standard 35 API gravity rating, the inlet manifold pressure can be slightly less than the value given in the RACK SETTING INFORMATION. If the fuel is rated below the standard rating, the inlet manifold pressure can be slightly more. Be sure the air cleaner and exhaust are not restricted when checking inlet manifold pressure.The components in a 4S6553 Instrument Group provide a means of reading engine RPM and inlet manifold pressure simultaneously. This group contains an instantaneous reading tachometer, and a gauge for reading inlet manifold pressure. Instructions (FE036044) included with this group, explain the testing procedure.Crankcase Pressure
Excessive crankcase pressure can be a result of combustion gas leaking past broken or damaged pistons and/or piston rings. This condition will usually be accompanied by irregular engine operation and excess fumes from crankcase breather opening. This pressure can cause the breather element to become restricted in an unusually short time. In addition, it can cause engine oil to leak past gaskets and seals that would function properly under normal conditions.Compression
Irregular (rough) engine operation can be caused by improperly adjusted or leaky valves. Operate the engine at RPM which makes the malfuction most pronounced. A non-firing or low compression cylinder can be located by momentarily loosening and then retightening fuel lines at the fuel injection pumps one at a time. Continue this until a loosened fuel injection line makes little or no difference in the engine operation. This same test can also indicate faulty fuel injection so further checking of the cylinder is necessary.Cylinder Condition
Engine cylinder condition can be analyzed with controlled pressure air through the engine cylinder precombustion chamber. Special Instruction (GMG00694) explains the procedure.3B7762 Tee3B7767 Nipple6K6875 Hose Assembly8M2744 Gauge1P5569 Tip7S8890 Adapter7S8895 Adapter8S2268 Tube Assembly9S7341 AdapterAir pressure regulatorAir escaping from the exhaust opening indicates exhaust valve leakage. Air escaping from the air inlet indicates inlet valve leakage. If air escapes from the crankcase breather during this test, it is an indication of piston, rings and/or liner faults.
MEASURING AIR FLOW
1-Air regulator. 2-6K6875 Hose Assembly and 7S8895 Adapter. 3-8S2268 Tube Assembly and 9S7341 Adapter. 4-8M2744 Gauge (0-100 PSI). 5-7S8890 Adapter. Parts not shown: 3B7762 Tee, 3B7767 Nipple, 1P5569 Tip.Cylinder Head
Original equipment cylinder heads for turbo-charged engines are equipped with valve seat inserts. Valve seat inserts are installed in replacement cylinder heads for all engines.Tools required to install valve guides are: 7S8858 Driver Bushing and 7S8859 Driver. The counterbore in the driven bushing mates with the counterbore in the cylinder head to limit driving the guide.Valve Clearance Setting
ADJUSTING VALVE CLEARANCE Precombustion Chamber Position
Use 5F8353 Wrench to remove and install chamber. Coat threads with 9M3710 Anti-Seize Compound.
PRECOMBUSTION CHAMBER POSITION
Install thinnest gasket first. Install precombustion chamber and tighten to 150 10 lb. ft. (20,7 1,4 mkg). If the glow plug opening is not positioned in the "go" range, remove the chamber and replace gasket with that called for in the diagram.Use gaskets to position precombustion chambers to prevent wiring interference.Fuel System
Difficulty within the fuel system can be classed in one of two groups: lack of fuel or too much fuel for proper combustion.Many times the fuel system is blamed when the fault lies elsewhere, especially when smoky exhaust is the problem. Smoky exhaust can be the result of a faulty fuel injection valve, but it can also be caused by lack of air for complete combustion, overloading at high altitude, excessive oil burning or lack of compression.Visual Inspection
1. Observe the fuel pressure gauge reading. Lack of pressure indicates difficulty in the supply side of the system.2. Check the fuel level in the supply tank and the fuel tank cap vent for being plugged.3. See that the vent valve is closed.4. Check for leakage in the fuel supply lines and components or for a kinked or restricted supply line.5. Replace the fuel filter element and clean the primary fuel filter if so equipped.6. Inspect the fuel bypass valve to see that it moves freely and that dirt is not holding the plunger off its seat. Be certain the spring has correct tension.7. Bleed the fuel system to remove trapped air.Testing Fuel Injection Equipment
A simple check can be made to determine which