90001-ZY6-000 Honda BOLT, FLANGE (8X55) (Honda Code 7636061).

Gasoline Starting Engine
Problem Solving
PROBLEM: Starting engine fails to crank when start switch is actuated. PROBABLE CAUSE:1. Low output from battery.2. Defectiveswiring or switch.3. Defective starter solenoid.4. Defective starting motor.5. Damaged starter pinion or flywheel ring gear.6. Mechanical failure of components which prevents crankshaft rotation. PROBLEM: Engine cranks but is hard to start or fails to start. PROBABLE CAUSE:1. Lack of fuel.2. Dirty or contaminated fuel.3. Weak or defective magneto.4. Defective spark plugs or wiring.5. Low compression.6. Restricted air cleaner. PROBLEM: Engine doesn't develop full power. PROBABLE CAUSE:1. Restricted air inlet.2. Fuel supply inadequate.3. Governor linkage stuck or restricted.4. Governor high idle setting incorrect. PROBLEM: Engine surges. PROBABLE CAUSE:1. Sticking or binding linkage.2. Weak or defective governor spring.3. Defective governor assembly. PROBLEM: Engine smoking. PROBABLE CAUSE:1. Insufficient inlet air.2. Excess fuel.3. Contaminated fuel.4. Oil loss into cylinders.5. Coolant entering the cylinder. PROBLEM: Engine overheats. PROBABLE CAUSE:1. Low diesel engine coolant level.2. Engine overloaded.3. Cooling system passages internally coated restricting coolant flow and reducing heat transfer.4. Air or combustion gases in the cooling system. PROBLEM: Cylinders misfiring. PROBABLE CAUSE:1. Insufficient fuel supply.2. Carboned or defective spark plugs.3. Defective magneto. PROBLEM: Insufficient fuel supply. PROBABLE CAUSE:1. Fuel supply tank empty or shut off.2. Fuel tank breather vent restricted.3. Loose or damage fuel line. PROBLEM: Low or no oil pressure. PROBABLE CAUSE:1. Low oil level.2. Damaged or restricted oil lines and manifolds.3. Oil filter restricted.4. Oil filter bypass valve stuck open.5. Oil pump malfunction. PROBLEM: Low compression. PROBABLE CAUSE:1. Cylinder head gasket leaking.2. Air cleaner element or air inlet restricted.3. Valves leaking.4. Piston rings leaking.5. Damaged piston.6. Leaking around spark plug threads. PROBLEM: Excessive lubricating oil consumption. PROBABLE CAUSE:1. Oil entering cylinder.2. Improper grade or type of oil.3. Engine overheating.4. Crankcase oil diluted.5. Oil level too high. PROBLEM: Will not crank diesel engine. PROBABLE CAUSE:1. Clutch plates worn.2. Broken clutch plates.3. Broken clutch or pinion shaft. PROBLEM: Control lever in pinion engaging position but pinion does not engage or does not stay engaged. PROBABLE CAUSE:1. Linkage out of adjustment or broken.2. Plunger stuck or binding.3. Plunger spring broken.Air Induction And Exhaust
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 inches (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 20 inches (508 mm) of water, difference in pressure.Measuring Inlet Manifold Pressure
By checking inlet manifold pressure, and comparing that pressure with the RACK SETTING INFORMATION, one can determine if an engine is operating efficiently. 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 reading than listed in the RACK SETTING INFORMATION. If the ambient air is less dense, the horsepower and inlet manifold pressure rating can be slightly lower. 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 INLET 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.
4S6553 INSTRUMENT GROUP
1. Lid. 2. 4S6997 Manifold Pressure Gauge. 3. Pressure tap fitting. 4. 4S6992 Differential Pressure Gauges. 5. 4S6991 Tachometer. 6. Zero adjustment screws. 7. 8M2743 Gauge.Exhaust temperature can be checked using the 1P3060 Pyrometer Group. Refer to the TOOL GUIDE. Special Instruction (GMG00697) explains the testing procedure.Checking Inlet Manifold Pressure at Full Load and Speed
Connect the components of the 4S6553 Instrument Group. With the engine governor control in the FULL LOAD position, apply the brakes until the engine speed falls to approximately 80% of the FULL LOAD speed. Slowly reduce the load (allowing the engine speed to increase) while observing the rise in both manifold pressure and engine rpm.The inlet manifold pressure will rise (as the load is decreased), reach a peak value, and fall off sharply. Record the peak manifold pressure and the speed at which it occurs. Compare reading with the RACK CHART.Checking Inlet Manifold Pressure at Torque Converter Stall Speed
Connect the components of the 4S6553 Instrument Group. Set the brakes, shift to 2nd gear forward and move the governor control to FULL LOAD. The torque converter is now in what is termed the stall condition and the engine rpm will be slowed to torque converter stall speed.
Continuous operation of the engine with the torque converter stalled, will cause overheating of the cooling system.
If the torque converter is operating within operating temperature and the specified efficiency limits (check the torque converter oil outlet pressure), the engine inlet manifold pressure can be use