955390 Volvo.Penta Hexagon screw

Troubleshooting Problems
Problem 1: Engine Crankshaft Will Not Turn When Start Switch Is On Probable Cause:1. Battery Has Low Output Make Reference to Problem 26.2. Wires Or Switches Have Defect Make Reference to Problem 26.3. Starting Motor Solenoid Has A Defect Make Reference to Problem 26.4. Starting Motor Has A Defect Make Reference to Problem 26.5. Inside Problem Prevents Engine Crankshaft From Turning If the crankshaft can not be turned after the driven equipment is disconnected, remove the fuel injection nozzles and check for fluid in the cylinders when the crankshaft is turned. If fluid in the cylinders is not the problem, the engine must be disassembled to check for other inside problems. Some of these inside problems are bearing seizure, piston seizure, or wrong pistons installed in the engine. Problem 2: Engine Will Not Start Probable Cause:1. Starting Motor Turns Too Slow Make reference to Problem 27.2. Dirty Fuel Filter Install new fuel filter.3. Dirty Or Broken Fuel Lines Clean or install new fuel lines as necessary.4. Fuel Transfer Pump At starting rpm, the minimum fuel pressure for fuel transfer pump must be 20 kPa (3 psi). If fuel pressure is less than 20 kPa (3 psi), change the fuel filter element. Look for air in the fuel system. If fuel pressure is still low, install a new fuel transfer pump.5. No Fuel To Cylinders Put fuel in fuel tank. "Prime" (remove the air and/or poor quality fuel) the fuel system.6. Poor Quality Fuel Remove the fuel from the fuel tank. Install a new fuel filter element. Put a good grade of clean fuel in the fuel tank. See Diesel Fuels and Your Engine, SEBD0717.7. Wrong Fuel Injection Timing Make adjustment to timing.8. Shutoff Solenoid Will Not Move To Extended Position The solenoid must get electricity to stop the engine. Operate the control for the shutoff solenoid and see if the solenoid makes a noise (clicking sound). If this sound can be heard and the engine will not start, remove the solenoid. Now see if the engine will start. If the engine starts, the shutoff solenoid either needs an adjustment or it is defective and replacement of the solenoid is necessary. Problem 3: Engine Misfires Or Runs Rough Probable Cause:1. Fuel Pressure Is Low Make sure there is fuel in the fuel tank. Look for leaks or defective bends in the fuel line between fuel tank and fuel transfer pump. Look for air in the fuel system. Check fuel pressure.If fuel pressure is lower than 170 kPa (25 psi) install a new filter element. The outlet pressure of the fuel transfer pump at full load must be 240 kPa (35 psi). If fuel pressure is still low, install a new fuel transfer pump.2. Air In Fuel System Find the air leak in the fuel system and correct it. If air is in the fuel system, it will probably get in on the suction side of fuel transfer pump.3. Leak Or Break In Fuel Line Between Fuel Injection Pump And Fuel Injection Nozzle Install a new fuel line.4. Wrong Valve Lash. Make adjustment according to the Subject, Valve Lash Setting.5. Defect In Fuel Injection Nozzle(s) Or Fuel Injection Pump(s) Run engine at rpm that misfires the most and runs the roughest. Then loosen a fuel line nut on the fuel injection nozzle for each cylinder, one at a time. Find the cylinder where a loosened fuel line nut does not change the way the engine runs. Test the fuel injection pump and fuel injection nozzle for that cylinder. Install new parts where needed.6. Wrong Fuel Injection Timing Make adjustment to timing.7. Bent Or Broken Push Rod Replacement of push rod is necessary.8. Fuel Has "Cloud Point" Higher Than Atmospheric Temperature ("Cloud Point"=Temperature Which Makes Wax Form In Fuel). Drain the fuel tank, lines, and fuel injection pump housing. Change the fuel filter. Fill the tank with fuel which has the correct "cloud point" and remove the air from the system with the priming pump. Problem 4: Stall At Low RPM Probable Cause:1. Fuel Pressure Is Low Make sure there is fuel in the fuel tank. Look for leaks or defective bends in the fuel line between fuel tank and fuel transfer pump. Look for air in the fuel system. Check fuel pressure.If fuel pressure is lower than 170 kPa (25 psi) install a new filter element. The outlet pressure of the fuel transfer pump at full load must be 240 kPa (35 psi). If fuel pressure is still low, install a new fuel transfer pump.2. Idle RPM Too Low Make adjustment to governor so idle rpm is the same as given in the TMI (Technical Marketing Information) or Fuel Setting And Related Information Fiche.3. Defect In Fuel Injection Nozzle(s) Install a new fuel injection nozzle.4. Engine Accessories Check engine accessories for damage and correct adjustment. If necessary, disconnect the accessories and test the engine.5. Defect In Fuel Injection Pump(s) Install new parts if needed. Problem 5: Sudden Changes In Engine Speed (rpm) Probable Cause:1. Failure Of Governor Or Fuel Injection Pump Look for damaged or broken springs, linkage or other parts. Remove the governor. Check for free travel of fuel rack. Be sure fuel injection pumps are installed correctly. Check for correct governor spring. Install new parts for those that have damage or defects. Problem 6: Not Enough Power Probable Cause:1. Poor Quality Fuel Remove the fuel from the fuel tank. Install a new fuel filter element. Put a good grade of clean fuel in the fuel tank.2. Fuel Pressure Is Low Make sure there is fuel in the fuel tank. Look for leaks or defective bends in the fuel line between fuel tank and fuel transfer pump. Look for air in the fuel system. Check fuel pressure.If fuel pressure is lower than 170 kPa (25 psi) install a new filter element. The outlet pressure of the fuel transfer pump at full load must be 240 kPa (35 psi). If fuel pressure is still low, install a new fuel