815094006 Mercury STOPPER

Troubleshooting Index
1. Engine Will Not Turn When Start Switch Is On.2. Engine Will Not Start.3. Engine Misfires Or Runs Rough.4. Stall At Low rpm.5. Sudden Changes In Engine rpm.6. Engine With Dashpot Governor Is Slow To Correct Speed Or Hunts (Changes Speed Constantly).7. Not Enough Power.8. Too Much Vibration.9. Loud Combustion Noise.10. Valve Train Noise (Clicking).11. Oil In Cooling System.12. Mechanical Noise (Knock) In Engine.13. Fuel Consumption Too High.14. Loud Valve Train Noise.15. Too Much Valve Lash.16. Valve Rotocoil Or Spring Lock Is Free.17. Oil At The Exhaust.18. Little Or No Valve Clearance.19. Engine Has Early Wear.20. Coolant In Lubrication Oil.21. Too Much Black Or Gray Smoke.22. Too Much White Or Blue Smoke.23. Engine Has Low Oil Pressure.24. Engines Uses Too Much Lubrication Oil.25. Engine Coolant Is Too Hot.26. Exhaust Temperature Is Too High.27. Starter Motor Does Not Turn.28. Alternator Gives No Charge.29. Alternator Charge Rate Is Low Or Not Regular.30. Alternator Charge Rate Is Too High.31. Alternator Has Noise.32. Rack Solenoid Does Not Stop Engine. Problem 1. Engine Crankshaft Will Not Turn When Start Switch Is On Probable Cause:1. Battery Has Low Output Make Reference to Item 27.2. Wires Or Switches Have Defect Make Reference to Item 27.3. Starter Motor Solenoid Has A Defect Make Reference to Item 27.4. Starter Motor Has A Defect Make Reference to Item 27.5. Inside Problem Prevents Engine Crankshaft From Turning If the crankshaft cannot be turned after the drive equipment is disconnected, remove the fuel nozzles and check for fluid in the cylinders while 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, wrong pistons installed in the engine, and valves making contact with pistons. Problem 2. Engine Will Not Start Probable Cause:1. Starter Motor Turns Too Slow Make Reference to Items 27 and 28.2. 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 from fuel transfer pump must be 35 kPa (5 psi). If fuel pressure is less than 35 kPa (5 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 tank. "Prime" (remove the air and/or low quality fuel) the fuel system.6. Bad Quality Fuel Remove the fuel from the fuel tank and fuel system. Install a new fuel filter element. Put a good grade of the correct clean fuel in the fuel tank. See FUELS FOR CATERPILLAR DIESEL ENGINES, Special Instruction Form No. SEHS7067 and MEASURING DIESEL FUEL API SPECIFIC GRAVITY, Special Instruction Form No. GMG00977.7. 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 shutoff solenoid. Now see if the engine will start. If the engine starts, the shutoff solenoid is bad. 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 bad bends in the fuel line between fuel tank and fuel transfer pump. Look for air in the fuel system, sticking, binding or defective fuel bypass valve. Check fuel pressure. The outlet pressure of the fuel transfer pump is 230 35 kPa (33 5 psi) at full load speed.If fuel pressure is lower than 140 kPa (20 psi), install a new filter element. It 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 Injection Pump And Injection Valve Install a new fuel line.4. Wrong Valve Clearance Make adjustment according to the Subject, VALVE CLEARANCE SETTING.5. Defect In Fuel Injection Nozzle(s) Or Injection Pump(s) Run at rpm that causes engine to misfire the most or run the roughest. Then loosen a fuel injection line nut at the valve cover base 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 injection pump and 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 bad bends in the fuel line between fuel tank and fuel transfer pump. Look for air in the fuel system, sticking, binding or defective fuel bypass valve. Check fuel pressure. The outlet pressure of the fuel transfer pump is 230 35 kPa (33 5 psi) at full load speed.If fuel pressure is lower than 140 kPa (20 psi) install a new filter element. 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 FUEL SETTING AND RELATED INFORMATION FICHE.3. Defect In Fuel Injection Nozzle(s) Install new fuel injection nozzle(s).4. Engine Accessories Check engine