11967 1 Mercruiser SCREW, (.437-14 x 3.00)

ENGINE WILL NOT START MISFIRING OR RUNNING ROUGH STALL AT LOW RPM SUDDEN CHANGES IN ENGINE SPEED NOT ENOUGH POWER TOO MUCH VIBRATION LOUD COMBUSTION NOISE (KNOCK) LOUD NOISE (CLICKING) FROM VALVE COMPARTMENT OIL IN COOLING SYSTEM MECHANICAL NOISE (KNOCK) IN ENGINE FUEL CONSUMPTION TOO HIGH LOUD NOISE FROM VALVES OR VALVE DRIVE COMPONENTS LITTLE MOVEMENT OF ROCKER ARM AND TOO MUCH VALVE CLEARANCE VALVE ROTOCOIL OR SPRING LOCK IS FREE OIL AT THE EXHAUST LITTLE OR NO VALVE CLEARANCE ENGINE HAS EARLY WEAR COOLANT IN LUBRICATION OIL TOO MUCH BLACK OR GRAY SMOKE TOO MUCH WHITE OR BLUE SMOKE ENGINE HAS LOW OIL PRESSURE ENGINE USES TOO MUCH LUBRICATION OIL ENGINE COOLANT IS TOO HOT STARTER MOTOR DOES NOT TURN ALTERNATOR GIVES NO CHARGE ALTERNATOR CHARGE RATE IS LOW OR NOT REGULAR ALTERNATOR CHARGE TOO HIGH (AS SHOWN BY LIGHTS BURNING OUT, BATTERY NEEDS TOO MUCH WATER) ALTERNATOR HAS NOISE EXHAUST TEMPERATURE IS TOO HIGH Fuel System
Either too much fuel or not enough fuel for combustion can be the cause of a problem in the fuel system.Many times work is done on the fuel system when the problem is really with some other part of the engine. The source of the problem is difficult to find, especially when smoke comes from the exhaust. Smoke that comes from the exhaust can be caused by a bad fuel injection valve, but it can also be caused by one or more of the reasons that follow:a. Not enough air for good combustion.b. An overload at high idle.c. Oil leakage into combustion chamber.d. Not enough compression.Fuel System Inspection
A problem with the components that send fuel to the engine can cause low fuel pressure. This can decrease engine performance.1. Check the fuel level in the fuel tank. Look at the cap for the fuel tank to make sure the vent is not filled with dirt.2. Check the fuel lines for fuel leakage. Be sure the fuel supply line does not have a restriction or a bad bend.3. Install a new fuel filter. Clean the primary fuel filter, if so equipped.4. To remove air from the fuel system, use one of the procedures that follow for the correct application:PC Engines:
(a) Use the priming pump to remove air from the low pressure side of the fuel system.(b) Loosen (one at a time) the fuel injection line nut one-half turn at the cylinder head. Use the priming pump until fuel without air flows from the loose connections, then tighten the nut. Repeat the procedure for each fuel injection line.DI Engines:
(a) Use the priming pump to remove air from the low pressure side of the fuel system.
When fuel injection lines are loosened or tightened on the fuel injection nozzles, two wrenches must be used. The nozzle must be held with a wrench or damage to the nozzle can result.
(b) Loosen one-half turn the fuel injection line nuts at the adapter in the cylinder head. Use the starter motor to turn the engine until fuel without air flows from the loose connections. Tighten the nuts. Because of the check assemblies in the injection pump outlets for the DI engine, the priming pump will not give enough pressure to remove air from the fuel injection lines.5. Inspect the fuel bypass valve to see that there is no restriction to good operation.Checking Engine Cylinders Separately
An easy check can be made to find the cylinder that runs rough (misfires) and cause black smoke to come out of the exhaust pipe.Run the engine at the speed that is the roughest. Loosen the fuel line nut at a fuel injection pump. This will stop the flow of fuel to that cylinder. Do this for each cylinder until a loosened fuel line is found that makes no difference in engine performance. Be sure to tighten each fuel line nut after the test before the next fuel line nut is loosened. Check each cylinder by this method. When a cylinder is found where the loosened fuel line nut does not make a difference in engine performance, test the injection pump and injection valve for that cylinder.Temperature of an exhaust manifold port, when the engine runs at low idle speed, can also be an indication of the condition of a fuel injection valve. Low temperature at an exhaust manifold port is an indication of no fuel to the cylinder. This can possibly be an indication of an injection valve with a defect. Extra high temperature at an exhaust manifold port can be an indication of too much fuel to the cylinder, also caused by an injection valve with a defect.Testing Capsule-Type Fuel Injection Nozzles
Precombustion Chamber Engines (PC)