Repair 7

When the oil pressure starts to drop in a diesel engine, problems set in. First, the oil is not fully spread across the engine, which contributes to further problems. Shaft bearings start to wear as a result, including the camshaft. Piston rings start to wear, leading to excessive oil burning. Overall, a snowball effect takes place, leading to eventual engine destruction. When the oil pressure goes low, all additives claim to "fix" the problem instantly. Correctly fixing the problem, however, involves extensive diagnosis, including analyzing the oil pump closely.

False Claims

Low oil pressure in a diesel engine indicates something is seriously wrong. Trying to use additives to correct low oil pressure is like putting a band aid on a broken leg. Some additive makers have been known to make false claims of correcting engine problems. For example, the Federal Trade Commission in 2001 brought charges against Zmax oil additive for deceptive advertising.

True Causes

The true causes of low oil pressure in a diesel engine are serious. First, check the oil level and type of oil you are using. The oil should be rated for diesel engines, and the proper viscosity must be used. The service department of the dealership that sells your make and model of vehicle can help you choose the right oil. If you are using the right oil, the next step is to suspect a faulty oil pump. Furthermore, Machinery Lubrication Magazine states that diesel fuel dilution causes low pressure at startup. A qualified diesel technician can assist you in diagnosing and correcting the problem.

Simple Cures

If the oil pressure is a little low, try some simple fixes. Using a thicker viscosity of oil might help. For example, suppose the manufacturer calls for using 5W-20 to 20W-30 for the oil weight. If you use 20W-30, this is slightly thicker. You are still staying within the recommended guidelines, but are using oil at the upper range of the recommended thickness scale. If you suspect fuel dilution, drain and change the oil and oil filter. This will get rid of the thinned out oil. You oil pump may be sensitive to changes like this, and perhaps the problem will self correct.

Steps To Take

Try the easy solutions first. If the oil pressure is just starting to go low, you may have to change the oil more often to overcome fuel dilution. Try to start your engine less frequently, as the experts state this leads to fuel dilution, particularly in cold weather. If the simple solutions do not resolve the problem, then professional expertise is needed to diagnose the root cause of the problem. Additives claim to correct problems, but these claims should be looked upon with skepticism.

The Duramax is a series of eight-cylinder diesel engines manufactured by General Motors and Isuzu since 2001. General Motors uses these engines in larger, heavy-duty trucks. For example, the 6.6-liter Duramax is an engine option in the 2002 Chevrolet Silverado 2500HD pickup truck. The water pump circulates coolant around the engine to prevent it from overheating. The water pump on a 2002 Duramax diesel engine is on the front of the engine and is accessible from the left-front wheelhouse of the vehicle.

Instructions

1

Disconnect the inner panel for the left-front wheelhouse with a socket wrench. Place a drain pan under the radiator drain, and remove the radiator drain plug. Drain the coolant into the drain pan, and replace the drain plug.

2

Disconnect the housing for the thermostat and the clutch for the cooling fan with a socket wrench. Remove the balancer from the crankshaft. Disconnect the mounting nuts for the outlet hose, and detach the hose from the water pump. Disconnect the retainer for the engine wiring harness from the outlet hose of the water pump.

3

Remove the mounting bolt from the water pump with a socket wrench. Record the locations of each bolt, since they have different lengths. Detach the water pump and its gasket from the engine.

4

Lubricate the gasket for the water pump with engine oil, and replace the gasket. Install the new water pump and tighten its mounting bolts to 15 foot-pounds with a torque wrench.

5

Connect the retainer for the engine wiring harness to the outlet hose for the water pump. Attach the outlet hose to the water pump and tighten its mounting nuts to 15 foot-pounds with a torque wrench. Replace the thermostat housing and crankshaft balancer with a socket wrench. Install the clutch for the cooling fan.

6

Fill the radiator with coolant. Replace the inner panel for the wheelhouse in the left-front fender.

There are a number of different fluids that are used in a General Motors or Chevrolet 6.5-liter diesel engine to keep it running smoothly and operating properly. Without the proper fluids, the trucks engine can be damaged by heat and friction that are generated as the engine runs. It is important to use the proper fluids in your diesel truck and keep the right amount of fluids in the engine at all times.

Oil

Engine oil is required for all gasoline and diesel engines. Oil provides the lubrication necessary to minimize friction between internal components. The 2011 Chevrolet Diesel Truck owners manual insert states that Chevrolet diesel engines need to use engine oil that is designated as API CJ-4 and has a viscosity of SAE 15W-40, unless you are in extremely cold temperatures, where SAE 5W-40 can be used to improve cold starting. Chevrolet states that you should not use 10W-30, 10W-40 or 20W-50 oils in your 6.5 diesel engine. Oil should be changed every 3,000 miles.

Oil Flushes and Additives

Chevrolet states that vehicle owners should not add any kind of additional fluid to the recommended engine oil of their diesel trucks. Chevrolet does not recommend using oil additives or engine oil system flushes. These treatments may void your vehicles warranty and cause damage.

Coolant

The 6.5-liter diesel should operate using a 50/50 mixture of DEX-COOL coolant and clean, drinking-quality water in the radiator and cooling system. The coolants purpose in the engine is to prevent overheating and extreme engine temperatures.

Other Fluids

Your 6.5-liter diesel engine and its various components rely on a number of different fluids to continue operating properly. These include DEXRON-VI automatic transmission fluid for the transmission and transfer case, GM-brand power steering and diesel exhaust fluid, and DOT-3 hydraulic brake fluid.

International Harvester manufactured the 7.3-liter diesel engines that appear in Ford trucks from 1988 to 1992. This engine is most common in Ford trucks with a rated carrying capacity of at least 1/2 ton. The 7.3-liter Ford diesel engine uses a single cylinder head for all eight cylinders in the engine. The cylinder head is on top of the engine block and is part of the combustion chamber. The procedure for removing the cylinder head from a 7.3-liter engine is the same for all Ford trucks.

Instructions

1

Disconnect the cables from the negative terminals of both batteries with a socket wrench. This prevents anyone from starting the engine while removing the cylinder head.

2

Put a drain pan under the radiator. Remove the drain plug with a socket wrench and allow the coolant in the radiator to drain into the pan. Store the coolant for later use.

3

Detach the shrouds for the radiator fan with a socket wrench. Disconnect the fan and clutch for the radiator as an assembly by using tools T83T-6312-A and T83T-6312-B. The mounting nut for the radiator fan and clutch has a left-hand thread, so you must turn it clockwise to remove the nut.

4

Label the electrical wiring on the alternator so you can connect it correctly later and detach the wiring from the alternator. Disconnect the bolts for the alternator and vacuum pump with a socket wrench. Remove these components from the engine block.

5

Disconnect the coolant hose from the cylinder head with a socket wrench. Remove the fuel injection pump from the engine block. Disconnect the intake manifold and valley cover from the engine block.

6

Raise the vehicle with a floor jack and support it with jack stands. Remove the exhaust pipes from the exhaust manifolds with a socket wrench. Disconnect the clamp and mounting bolt for the oil dipstick tube. Detach the oil dipstick tube from the cylinder head and lower the vehicle.

7

Disconnect the valve covers with a socket wrench and remove the rocker arms from the engine block. Record the position of each push rod, so you can re-install them correctly later. Remove the push rods from the engine block.

8

Remove the fuel injector nozzles and glow plugs from the engine block with a socket wrench. Disconnect the mounting bolts for the cylinder head with a socket wrench. Install lifting eyes on each end of the cylinder block with tool T70P-6000.

9

Lift the cylinder head from the engine block with the lifting eyes. Use caution to prevent the pre-chambers of the cylinder head from falling onto the engine when you remove the cylinder head.

General Motors made an eight-cylinder 6.2 L diesel engine from 1982 until 1993. It was an optional engine that was most common on larger pickup trucks. The fuel injectors for this engine are on top of the engine, and each injector sends fuel to a cylinder in a specific sequence. The majority of the work of installing a fuel injector in a 6.2 L engine is removing the fuel lines so you can remove the old fuel injector.

Instructions

1

Disconnect the negative battery cable with a socket wrench to prevent anyone from starting the engine during the procedure. Remove the clip on the fuel return line, and detach the fuel return line from the fuel injectors.

2

Remove the air cleaner bracket from the valve cover with a socket wrench. Disconnect the crankcase ventilator bracket. Detach the fuel lines from the secondary fuel filter adapter and disconnect the secondary filter adapter. Release the clamp on the vacuum pump and move the pump aside to access the bolts for the intake manifold. Disconnect the intake manifold bolts and remove the intake manifold from the engine.

3

Cover the engine with GM part no. J-29664-1 to protect the open engine from debris. Disconnect the clips on the fuel injector lines from the loom brackets. Remove the fuel injector lines from the injector nozzles and place caps over the nozzles.

4

Detach the injector lines from the injector pump. Plug the open ends of the fuel lines with clean cloth to prevent contamination of the fuel lines.

5

Remove the fuel injector from the engine by turning the 30 mm hex portion of the fuel injector counterclockwise with GM special tool J-29873. Discard the gasket for the fuel injector.

6

Install a new fuel injector and gasket by turning the 30 mm hex portion of the injector clockwise with GM special tool J-29873. Tighten the injector to 50 foot-pounds with the special tool and a torque wrench.

7

Remove the cloth from the ends of the fuel lines and connect the fuel lines to the injectors. Tighten the retaining nut for the fuel line to 20 foot-pounds with a torque wrench. Complete the installation of the fuel injector by performing Steps 1 through 3 in reverse sequence.

The 1999 Ford F-250 is a diesel truck that many people use to haul heavy items with good fuel economy. If your F-250 is having a hard time starting, there are a few things that you can do before you get it towed to a repair shop. You dont have to be a car mechanic to get your diesel working again. You can do it yourself with little hassle and minimal knowledge of truck repair.

Instructions

1

Insert your key into the F-250s ignition and then try to start the truck. Check the electrical panel on the dashboard. Look at the battery meter and the gas gauge on the dashboard. If your truck does not have enough gas to start, fill the tank with diesel.

2

Use the applicable fuel for the truck. If you are using winter diesel in the summer, you will need to change the fuel. Summer diesel should not be used in the winter. Use a siphon to pump the gas out of the trucks gas tank.

3

Insert one end of the hose into the gas tank. Insert the other end into an empty container. Pump the siphon hose to siphon the gas out of the tank and into the container. Fill the gas tank with the applicable diesel.

4

Check the battery connections to the battery if your gauge indicated that there was a low charge. Open the hood and locate the battery next to the engine. Make sure that the battery connections are properly connected to the terminals. The red cable should be on the positive (+) terminal and the black cable should be on the negative terminal (-). Use a pair of channel locks to secure the connections.

5

Place the terminal leads of the voltmeter to your batterys connections. The diesel truck uses a 12-volt battery. You should get an 11 to 12 volt reading on the voltmeters display. If you dont get an 11 to 12 volt reading from the voltmeter, replace the battery.

6

Jack the front end of the truck up with a jack and then locate the small black box on the bottom of the engine. This is the starter. Have a friend turn the ignition and listen to the starter. If you hear buzzing or clicking coming from the starter, you need to have it replaced by a certified technician.

A diesel exhaust system is designed to remove the emissions from a diesel engine, which differs from a gasoline engine in several ways. The biggest is that diesel engines dont have spark plugs: The diesel fuel ignites spontaneously in the engine rather than needing a spark to ignite. A diesel exhaust system is similar to a gasoline exhaust system in layout, but the specifics differ slightly and requires attention when you upgrade it.

Instructions

1

Raise the vehicle up on a jack or hydraulic lift so that you can upgrade the diesel exhaust system safely.

2

Locate the turbo in the engine and remove the band clamp connecting it to the downpipe with a screwdriver.

3

Disconnect the down pipe from the transmission and the muffler with a welding torch or simply by removing the support bolts, depending on the vehicle.

4

Detach the muffler and the catalytic converter if necessary. Not every exhaust system upgrade requires it, but if a new muffler or converter is involved, the old ones should be removed. You can use either a blowtorch or wrenches to remove the bolts, depending on how they are secured.

5

Install the new downpipe in position, but do not tighten it in place just yet. You want it connected to the turbo firmly, but loose enough you can adjust its alignment once other parts of the diesel exhaust system are installed. You can use a bungee cord or rubber hangers to do this if the downpipe isnt otherwise set up for it.

6

Install the new muffler and/or catalytic converter, if appropriate. Like the downpipe, you want mufflers and catalytic converters to be fitted into position but not tightened or welded into place until you have aligned them properly with the rest of the diesel exhaust system.

7

Connect the straight pipe between the muffler and the downpipe, clamping it into place but still keeping it loose enough to adjust. You may need to adjust the size of the pipe in order to fit the proper distance between the downpipe and the muffler.

8

Attach the hangers and clamps to the diesel exhaust system, checking to make sure that each one is aligned and fits where it should.

9

Connect the tail pipe behind the muffler, leaving it fitted in place but loosely attached, as with the rest of the diesel exhaust system.

10

Check the alignment and clearance of each component in the exhaust system, starting with the downpipe and moving back towards the tail pipe. At each step, you can tighten the clamps or weld the seals for the respective parts, moving step by step through each portion of the system.

11

Tighten the clamp between the downpipe and the turbo, which should complete the upgrade.

12

Check the system for any leaks or gaps. You may want to start the engine and check for any exhaust emissions emerging where they shouldnt. You can seal any leaks with a soldering iron.

13

Lower the vehicle off the lift.

The 7.3-liter Ford diesel is an engine with high ratings for fuel economy. If you are having problems with your 7.3-liter Ford diesel, you can do several things before you take it to a service center. Diesel engines are not very hard to work on. Most of the troubleshooting can be done without invasive repairs to the engine and minimal knowledge of how the engine works. Common issues reside in incorrect fuel, a bad starter or leaks from the engine.

Instructions

1

Insert and partly turn the key, to engage the Ford electrical panel. Look over the fuel gauge and make a note if there is not enough diesel in the tank to start the engine. Low fuel prevents an engine from starting.

2

Replace the fuel in the tank with the proper diesel. Changing diesel according to the season is imperative. Summer diesel will be cloudy in the winter -- this is the presence of condensation in the tank.

3

Use a siphon hose to remove the diesel from the tank. Put one end of the siphon pump into the fuel tank and then put the other end of the siphon pump into an empty gas container. Pump the siphon until the tank is empty. Fill the tank with the proper kind of diesel fuel.

4

Raise your 7.3-liter Ford with a jack, so you can get under the vehicle. Look for the small box next to the engine block on the right side of the vehicle. This is the starter. Get a helper to turn the ignition. Listen to the starter while the ignition is cranking. If you hear a clicking or a buzzing noise, have the starter replaced by a certified technician.

5

Look around the Ford for any leaks. Leaks can inhibit the car from starting properly. If you do find leaks, have the vehicle towed, or drive it to a service shop to have the leaked repaired.

International Harvester Corp. made a series of eight-cylinder diesel engines for use in Ford F-series pickup trucks from 1982 to 1994. These engines used indirect injection, a form of mechanical fuel injection that does not require electronic control. The 6.9-liter version of the International diesel engine was in production from 1983 to 1987. The procedure for removing the fuel injectors is generally the same for all Ford vehicles that have a 6.9-liter International diesel engine.

Instructions

1

Clean the fuel injector nozzles and the surrounding area with clean fuel oil to avoid contaminating the engine when you remove the fuel injectors. Clean the fuel line connections to the fuel injector to keep debris out of the fuel system. Blow the fuel injectors clean with an air compressor.

2

Release the clamps on the fuel lines to the fuel injectors, and disconnect the fuel lines from the fuel injectors. Remove the leak-off tees from the fuel injectors, and move them out of the way. Cover the open ends of the fuel injectors with plastic caps to keep dirt out of the fuel injectors.

3

Turn the fuel injectors counterclockwise with a socket wrench, and remove them from the injector bores. Cover the nozzle ends of the fuel injectors with plastic caps to avoid fuel contamination.

4

Extract the copper gasket from the injector bore with special tool T71P-19703-C, if the gasket is not on the fuel injector nozzle.

5

Store the fuel injectors in a holder with numbered holes. Place each fuel injector in the hole corresponding to that fuel injectors cylinder number. This ensures that you will reinstall each fuel injector into the correct injector bore.

Power Stroke engines appear in heavy Ford trucks manufactured since 1994. They use diesel fuel and typically have a turbocharger. The first Power Stroke engine had a displacement of 7.3 liters and was in production from 1994 to 2003. The exhaust manifold collects the exhaust gases from the cylinders, and each side of the engine typically has its own exhaust manifold. The most common reason for replacing the exhaust manifold is rust caused by the exhaust gases.

Instructions

1

Remove the cables from the negative terminals of both batteries with a socket wrench. This prevents anyone from accidentally starting the engine while you are replacing the exhaust manifold.

2

Access the right exhaust manifold from the top of the engine compartment. Bend the tabs on the attaching bolts for the right exhaust manifold, and disconnect the inlet pipe of the right muffler from the right exhaust manifold with a socket wrench.

3

Raise the vehicle and support it on jack stands. Access the left exhaust manifold from underneath the vehicle, and bend the tabs on the attaching bolts for the left exhaust manifold. Disconnect the inlet pipe of the left muffler from the left exhaust manifold with a socket wrench.

4

Clean the cylinder heads with a shop towel, and apply anti-seize compound to the threads on the new exhaust manifolds. Connect the new left exhaust manifold with a new gasket and locking tabs. Tighten the mounting bolts for the left exhaust manifold to 45 foot-pounds with a torque wrench. Bend the locking tabs over the bolt heads to secure the bolts.

5

Lower the vehicle and connect the new right exhaust manifold with a new gasket and locking tabs. Tighten the mounting bolts for the right exhaust manifold to 45 foot-pounds with a torque wrench. Bend the locking tabs over the bolt heads to secure the bolts.

6

Connect the cable to the negative terminal for both batteries with a socket wrench. Start the engine and correct any leaks in the exhaust system.

First available from GM in 1982, the 6.2L diesel engine was originally an option for sports utility vehicles, full-size pickup trucks, and other utility vehicles. With the dual perks of added fuel economy and durability, 6.2L diesel engines in GM two-wheel drive (2WD) and four-wheel drive (4WD) trucks were given gross vehicle weight ratings of up to 10,000 pounds. Additionally-equipped vehicles boast a capacity of over 13,000 pounds. A strong engine requires regular tune-ups and care to stay in prime operating condition.

Oil Lubricant

Oil lubricant is a necessity for the proper operation of the 6.2L diesel engine. Used for the lubrication of the engine, the oil for diesel engines is specially formulated and must remain at a certain level and consistency to provide the best functionality. Oil should be checked a minimum of once weekly. A common occurrence is the immediate change of newly-replaced oil to a dark black color after only a brief running of the engine. This does not mean that anything is wrong with the oil, but is rather a side-effect of the engine. Knowing how to change the oil can also save the owner money, since professionals charge as much as four times the amount to change fluids in a diesel engine than they charge for a regular gas engine.

Oil Filter

When changing the oil, the oil filter should be changed as well. Consulting the manual for the particular vehicle will inform owners of the optimal and maximum time allowed between filter changes. However, due to the heat and pressure generated by a diesel engine, the oil and filter may become contaminated more quickly that in a non-diesel engine vehicle.

Mechanical Injection Pump

The mechanical injection pump assists in the movement of the diesel fuel throughout the engine; therefore, it is important to ensure that no leakage is occurring. It is not uncommon for the seals on the injection pump to shrink when cold and allow fuel to leak out. At times, this problem is corrected through the warming of the engine, which causes the seal to swell, plugging any leaking. In order to check and perform repairs on the injection pump, it is necessary to remove the oil filler, intake manifold, and bolts. Be sure that the engine has fully cooled before attempting to work on any component. To gain access to these components, the crankshaft should be slowly turned in a clockwise direction with a 24 mm socket wrench. All wires and hoses should be removed from the pump, if it is necessary to separate it from the engine. Injector lines can be tricky, so it is important to be careful. In addition, ground wires should be removed from the batteries to avoid any mishaps.

Diesel engines are more commonly found on larger trucks. The standard engine in a 2004 Dodge Ram 2500 is a six-cylinder, 5.9-liter, turbocharged diesel engine. This engine uses a high-pressure fuel injected system to deliver fuel to the engine. The fuel injectors on the 2004 Dodge diesel engine are located on top of the engine. Removal requires a special tool. You will also need to remove the fuel in the fuel lines before replacing the injectors.

Instructions

1

Loosen the bleed bolt on the fuel rail with a socket wrench. Push the fuel primer on the fuel transfer pump until the fuel coming from the bleed valve no longer has air bubbles. Tighten the bleed bolt to 72 inch-pounds with a torque wrench.

2

Disconnect the negative battery cable by loosening the terminal nut with a socket wrench. This will prevent the accidental discharge of fuel as you remove the fuel injectors. Disconnect the valve cover with a socket wrench and detach the fuel lines from the fuel injectors.

3

Remove the retaining nut for the high-pressure fuel connector on each fuel injector. Disconnect the high-pressure connectors from the fuel injectors with tool 9015.

4

Disconnect the exhaust rocker arms with a socket wrench. Remove the retaining nuts from the solenoid wire, located on top of the fuel injectors. Disconnect the hold-down clamp bolts on the fuel injector. Remove the rocker-housing bolt with a socket wrench.

5

Connect the lower half of the mounting stud on tool 9010-2004 to the center of the bridge for the rocker housing. Connect the upper half of the mounting stud on tool 9010-2004 to the lower half of the mounting stud.

6

Connect the handle of tool 9010-2004 to the mounting stud on the tool. Tighten the nut on the tool to loosely connect the handle to the mounting stud. Connect the lower half of the clam shells on the special tool to the sides of the fuel injector. Connect the upper half of the clam shells to the head of the tool handle.

7

Slide the retaining sleeve over the pivoting handle of tool 9010-2004. Push the handle of the tool down to force the fuel injectors out of the cylinder heads. Remove the fuel injectors from the cylinder heads.

The 7.3-liter diesel engine made by Ford from 1994 to 2002 is commonly found in heavy trucks from this period. This engine employs fuel injection to send fuel into the engine under high pressure. Each cylinder of the engine has its own fuel injector, which delivers the fuel in an electronically-controlled sequence. You can remove and install the fuel injectors on this diesel engine individually with a special tool.

Instructions

1

Disconnect the mounting bolts for the valve cover with a socket wrench and remove the valve cover. Detach the wiring harnesses from the fuel injectors.

2

Disconnect the oil rail drain plugs and fuel rail drain plugs with a socket wrench. Disconnect the oil deflector by removing its retaining screw.

3

Remove the mounting bolt on the outboard side of the fuel injector with a socket wrench. Disconnect the retaining hardware from the heater distribution box, including the screws, nuts and clips. Remove the heater distribution box.

4

Connect the injector remover no. T94T-9000-AH1 to the fuel injector plate with the injector removers screw. Tighten the screw to lift the fuel injector from the injector bore. Discard the copper washers for the fuel injector.

5

Clean the injector bore with the rotunda injector sleeve brush and a shop towel. Mount a new copper washer to the new fuel injector and coat the fuel injector with engine oil to lubricate it.

6

Place the fuel injectors into the injector bore and ensure that you properly seat the O-rings. Position the injector replacer No. T94T-9000-AH2 between the fuel injector and its hold-down plate. Tighten the bolt on the injector replacer to fully seat the fuel injector into the injector bore.

7

Perform steps one through three in reverse order to complete the fuel injector replacement. Torque the retaining screw on the oil deflector to 108 inch-pounds with a torque wrench. Torque the fuel rail drain plugs to 96 inch-pounds and torque the oil rail drain plugs to 53 inch-pounds.