Repair And Fix it

All vehicles have at least one pipe with a flange connection. The front pipe or header pipe bolted to the manifold uses a flange of some type. Many modern vehicles now connect other components, such as catalytic converters, downstream exhaust pipes and even mufflers, with flange connections. With the car on a lift and a mechanic that knows what he is doing, the repair could take a mere few minutes. With a home repair mechanic laying on his back with limited tools, the repair could become complicated.

Instructions

1

Inspect the pipe with the leaking flange gasket caully before attempting to disconnect it. Front-pipe-to-manifold flanges often require the rear flange to the converter or pipe be separated in order to access the leaking gasket. Sometimes unhooking an exhaust hanger somewhere down the exhaust stream might allow enough flexibility to forgo the rear flange disconnection.

2

Determine how the flange is connected. All front-pipe-to-manifold flanges are secured by nuts to the studs of the manifold. Downstream flange connections may use studs on one side and nuts on the other or simple nuts and bolts. Downstream studs can be distinguished by round heads which, unlike a hex bolt head, cannot be held with a wrench. Studs have grooved notches in their shafts and do not require a box-end wrench for removing the nut. Nut and bolt connections will require the bolt of the head be held stationary (with the wrench) while a ratchet and socket loosen the nut (or another wrench).

3

Disconnect the flange hardware. If necessary, heat the nuts of the connection with an oxyacetylene torch. Using a portable propane torch may not heat the nut up enough or could take a considerable amount of time. Heat just the edges of the nut and not the bolt. This will expand the nut. Once the nut is cherry red, turn off the torch and remove the nut. For front pipes, a ratchet, long extension and socket are most likely required.

4

Repeat for each nut and stud/bolt connection of the flange until all retaining hardware is removed. The studs will remain intact on their respective exhaust components.

5

Separate the flange connection. This is where the exhaust pipe hanger tool may come in handy. Releasing one or more exhaust hangers near the flange connection may give the exhaust system enough flexibility to access the mating surfaces of each mating flange. As mentioned earlier, it may also require separating the other connection of the exhaust component with the compromised flange gasket.

6

Clean each flange connections mating surface with emery cloth or medium-grit sandpaper, after allowing the exhaust system to cool down, if a torch was used.

7

Apply a level amount of high-temp Perma-Tex (O2 sensor-safe) compound on both sides of the gasket. Place the gasket between the flanges. On most flange connections, theres a small piece of pipe protruding on the inside of the flange to place the gasket on, depending on the type of application. Some front pipe gaskets are called "donut" gaskets and fit into a ball-flared exhaust pipe.

8

Reconnect the flange connection, after replacing the system on hangers, if applicable, with new hardware (nuts, bolts, washers and lock washers).

9

Start the vehicle and check the flange connection for leaks. If necessary, re-tighten the hardware.

Intake gaskets seal gaps between the intake manifold and the cylinder head. They are made in thicknesses ranging from 0.060 inch to 0.120 inch. If too much air gets into the system, the car will not run properly.

Intake Manifold

Gaskets are located throughout the engine, but one of the most important parts of the engine is the intake manifold. The intake manifold regulates the amount of air and fuel your engine gets to create the combustible reactions that power the business. The gaskets can withstand temperatures of 500 degrees Fahrenheit and higher. Some gaskets are made from high-temperature plastic that actually cools the air that passes through them.

Gasket Problem Symptoms

You know that your intake gaskets are no longer doing their job if you start seeing puddles forming under the car when it is in park or when you see a leak in the coolant system. Also, if your engine is rough and slightly jerky, or if you hear whistling from the engine taking in excess air, you have problems with your gaskets.

Repair

A vacuum gauge that checks manifold pressure is used to find the leak. All coolant must be drained from the vehicle and the manifold must be removed in order to replace the gaskets.

Warning

In the book, "Small Black Chevy Engine Buildups," the editors write that with too much air "your engine will turn into melted cheesecake; too little and itll drive like melted cheesecake."

Manufactured for the export market, the Mazda 626 first appeared in the U.S. in 1979. The 1999 version of the 626 is a four-door family sedan that was powered by a 2.0-liter, inline four-cylinder engine that produced 125 horsepower and 127 foot-pounds of torque. A leaking gasket that caused poor engine performance was one of the engines issues.

Instructions

1

Disconnect the negative (ground) battery cable. Remove the timing belt. Remove the front exhaust pipe. Remove the air cleaner. Remove the accelerator cable. Disconnect the fuel hose. Remove the ignition coil.

2

Drain the engine coolant. Verify the engine oil level. Inspect for engine oil, engine coolant and fuel leakage. Inspect the pulleys and the drive belt for runout and contact.

3

Hold the camshaft by using a wrench on the cast hexagon, and loosen the camshaft pulley lock bolt. Loosen the camshaft cap bolts in two or three steps. Arrange the removed camshaft caps to ensure correct placement during installation. Temporarily install the number three engine mount rubber to support the engine. Loosen the cylinder head bolts in two or three steps. Remove the cylinder head. Remove the old head gasket. Clean the surface of the block from any dirt and debris with a degreaser. Place the new head gasket on the block.

4

Measure the length of each bolt used to tighten the cylinder head. Replace any that exceed the maximum length. Standard length is 4.103 to 4.125 inches. Maximum length would be 4.154 inches. Tighten the cylinder head bolts in two or three steps. Tightening torque shouldnt exceed 16.2 foot-pounds for each step. To install everything back, just follow the removal sequence in reverse. Remember to connect the negative battery cable back to the battery.

The GL1100 Gold Wing was introduced in 1980 and was based off the GL1000. The GL1100 was equipped with an 1,085-cc displacement, liquid-cooled opposed, four-cylinder engine. High performance valve timing and 30-mm bore carburetors contributed to its well deserved reputation of power and reliability. Performing engine repairs, such as general maintenance and routine adjustments, are in general not difficult on this motorcycle. However, replacing the head gasket is a challenging repair job. This repair job can be done without removing the engine from the motorcycle.

Instructions

1

Lift the motorcycle onto its center stand. Drain the coolant from the petcock at the bottom of the radiator into a drain pan. Dispose of the used antifreeze in accordance with local disposal laws. Remove the black bolts at the bottom of the radiator and slide the radiator forward. Remove spark plug wires from the spark plugs and set them aside.

2

Remove the eight bolts holding the plastic camshaft belt covers. Remove the camshaft belt covers and set them aside. Mark the position of the cam sprockets with a tic-mark on the cylinder block and a matching mark on the camshaft sprocket. Loosen the timing belt tensioners and remove the timing belt.

3

Remove the fuel pump if working on the right side of the engine. Remove the electronic ignition reluctor and cover if working on the left side of the engine. Remove the four bolts holding the valve covers and set the covers aside. Remove the four bolts holding down the intake manifolds.

4

Remove the six bolts holding the rocker shaft covers and remove rocker shafts. Remove the two bolts holding the camshaft pulley back plate. Tap the rocker shaft with a rubber mallet if necessary to assist in removal.

5

Remove the exhaust manifold bolts. Remove the six 10-mm cylinder head bolts and the the one small 6-mm bolt at bottom of head. Tap the head off using a rubber mallet. Bump the engine with the starter if the head is difficult to remove. This method uses the natural compression of the engine to pop the head loose.

6

Remove the oil restrictor orifice from crankcase. Remove all traces of old head gasket with a gasket scraper and rag. Ensure the block and head mating surfaces are clean, shiny and all traces of the old head gasket are removed. Clean the oil restrictor and ensure no sludge or other dirt is in the orifice passage in the block. Clean all carbon from the head using a wire brush and scraper. Check the head check for cracks or other damage. Repair any problems with the head as required.

7

Install the clean oil orifice using two new O rings. Replace O rings on the head water pipe with new ones and lubricate them with motor oil. Install the head onto the block finger tight using a new head gasket. Do not use any kind of sealer on the gasket, it must be installed dry.

8

Tighten the six 10-mm head bolts to 40 ft-lb with a torque wrench in a crisscross pattern. Install the 6-mm bolt at bottom of the head and torque to 10 ft-lb. Install the intake manifolds with the correct bolts. Ensure the manifold O rings are in good condition or replace as required.

9

Install the camshaft in the head and tighten the six camshaft bolts to 21 ft-lb. Install the camshaft pulley back plate using a new gasket and tighten the bolts to 9 ft-lb. Install the new timing belts using the alignment marks from Step 2 as erence. Tighten down the timing belt adjusters when everything is lined up. Ensure everything is correct before proceeding to the next steps.

10

Install the electronic ignition reluctor and cover plate or fuel pump as required. Replace the exhaust manifold bolts. Replace the valve cover and radiator bolts. Fill the radiator up to the recommended level with new antifreeze. Replace the spark plug wires onto the spark plugs.

11

Start the engine and check for leaks in the cooling system. Add coolant as necessary when the engine warms up to normal operating temperature.

The VR6 family of engines is a series of six-cylinder engines that Volkswagen Group has manufactured since 1991. These engines appear in a variety of Volkswagen cars, such as the Volkswagen Golf, new Beetle and Passat. The VR6 engines have staggered cylinders within the cylinder block and only require one cylinder head for all six cylinders. The removal of the cylinder head from a VR6 engine requires you to replace its gasket.

Instructions

1

Disconnect the cables from the battery terminals with a socket wrench and remove the battery from the vehicle. Remove the air cleaner, mass air flow sensor and air inlet duct from the intake manifold.

2

Open the cap on the radiator, and place a drain pan below the drain plug under the intake manifold. Open the drain plug with a socket wrench and allow the coolant to drain into the pan. Replace the drain plug.

3

Remove the trim cover from the engine with a socket wrench. Disconnect the distributor cap from the vehicle with the ignition wires still attached. Detach the throttle cable from the intake manifold and disconnect the upper intake manifold from the engine block. Remove the fuel lines and electrical connectors from the fuel injectors. Detach the coolant hoses from the engine block with a socket wrench.

4

Screw an 8 x 10 mm bolt into the tensioner for the accessory drive belt to relieve the tension on the drive belt. Remove the drive belt from its pulleys and unscrew the bolt from the tensioner. Disconnect the alternator and the tensioner for the accessory drive belt.

5

Remove the heat shield from both exhaust manifolds with a socket wrench and disconnect the exhaust manifolds from the engine. Disconnect the mounting bolt from the cover of the timing chain and remove the timing chain cover. Remove the cover from the cylinder head and turn the crankshaft clockwise to align its timing marks. Mark the timing chain with white paint to indicate its direction of rotation.

6

Hold each camshaft in place with a 24 mm wrench and disconnect the camshaft sprockets from the camshafts with a socket wrench. Remove the cylinder head bolts from the cylinder head and lift the cylinder head from the engine block.

7

Remove the cylinder head gasket from the engine block. Clean any traces of the gasket from the cylinder head and engine block with a gasket scraper. Mount the new gasket onto the engine block with the word "TOP" facing up. Place the cylinder head over the dowels on the engine block.

8

Fasten new mounting bolts to the cylinder head by hand. Tighten the bolts to 30 foot-pounds with a torque wrench on the first pass, then tighten them to 44 foot-pounds on the second pass. Tighten the bolts by 1/4 turn on the third pass, then tighten them an additional 1/4 turn on the fourth pass.

9

Turn the crankshaft clockwise to align its timing marks again and lock the camshafts in place with special tool 3268. Mount the camshaft sprockets with the timing chain to the camshafts and fasten the mounting bolts for the sprockets with a 24 mm wrench. Mount the distributor drive on the camshaft and tighten the mounting bolts for the camshaft sprockets to 74 foot-pounds.

10

Connect the timing chain tensioner and the upper cover for the timing chain temporarily. Remove special tool 3268 from the camshafts and turn the crankshaft four complete turns clockwise. Tighten the mounting bolts for the upper timing chain cover to 82 inch-pounds with a torque wrench. Tighten the mounting bolt for the tensioner to 15 foot-pounds.

11

Replace the cover for the cylinder head with a socket wrench. Install the intake manifold and exhaust manifolds to 18 foot-pounds with a torque wrench. Attach the drive belt for the alternator belt and adjust its tension with the belt tensioner. Connect the coolant hoses to the engine block. Install the electrical connectors and fuel lines for the fuel injectors.

12

Install the upper intake manifold to the engine block with a socket wrench. Connect any electrical wiring and vacuum lines that you removed from the upper intake manifold. Attach the throttle cable and distributor cap assembly to the upper intake manifold. Replace the trim cover for the engine.

13

Install the battery, and attach the cables to the battery with a socket wrench. Fill the radiator with coolant. Replace the oil and oil filter.

As the engine in your Jeep Comanche runs, hot exhaust gases are expelled from the combustion chamber into the exhaust manifold. The gases are kept in check by a series of exhaust gaskets, most notably the exhaust manifold gasket. If the exhaust manifold gasket is damaged or leaking, the engine will produce excessive noise, and the exhaust gases will escape into the engine compartment instead of exiting out the tailpipe as they should. Replacing the gasket is fairly straightforward, and you will need only a few tools to complete the job.

Instructions

1

Raise the hood of your Comanche and prop it open. Remove the negative cable from the battery by turning the bolt counterclockwise with the wrench.

2

Locate the exhaust manifold bolts and spray them with the penetrating oil. The bolts are usually corroded into place, so if possible allow the oil to soak into the bolts for a few hours.

3

Loosen the exhaust manifold bolts by turning them counterclockwise with the socket. Pull the exhaust manifold from the engine. Remove any of the old gasket with the scraper.

4

Coat the exhaust manifold bolts with anti-seize compound. Slide the new gasket into place between the exhaust manifold and the engine. Tighten the exhaust manifold bolts by turning them clockwise with the socket. Start with the inside bolts and work toward the outside as you tighten.

5

Reattach the negative cable to the battery by turning the bolt clockwise with the wrench. Start the engine and check for exhaust leaks.

A faulty head gasket can be a very serious problem for the health of an engine, allowing engine coolant to leak into combustion chambers and causing hydro lock. Hydro lock occurs when engine coolant enters the combustion chamber of an engine and cannot be compressed by the upward motion of the piston, usually resulting in catastrophic engine failure.

Instructions

1

Remove necessary parts, including the throttle linkage from the throttle body, air-conditioning compressor, alternator, power-steering pump, drive belts, intake manifold, intake manifold gasket as well as the exhaust manifold attached to the cylinder head with the faulty gasket.

2

Disassemble and remove the cylinder head by removing the valve cover from the top of the cylinder head with a box end wrench, then remove the rocker arms using a socket wrench and pull out the pushrods. Next, easily remove the cylinder head bolts and the head from the engine.

3

Place the new gasket on the engine block and place the cylinder head on top. Torque cylinder head bolts to 65 pound-feet using a torque wrench while making sure to tighten bolts in a crisscross pattern. Torque should be applied in 20 foot-pound increments to all bolts.

4

Reassemble engine components in reverse disassembly order, starting with the exhaust manifold. Replace all gaskets and tighten all fasteners using the torque wrench to factory specifications.

Sometimes a gasket seal needs a little extra reinforcement. This is where gasket sealer comes in, as it gives an extra sealing capacity to a gasket after it has been applied.

Sealer Features

When using a gasket sealer on a gasket, it starts off in the form of a liquid. However, after it is applied it changes form. Although it completely goes from liquid to become solid in form, it still maintains a level of flexibility.

Sealer Types

Any metal surface that has areas within it that need sealing, such as pores, can benefit from gasket sealer. There are many available types of gasket sealer on the market today, such as liquid silicone. Hylomar and Permatex are two other kinds of gasket sealer that are fairly common.

Sealer Use

A gasket sealer can be used on cars with caution, as it is not for all types of gaskets. A coated head gasket should never have gasket sealer applied to it. Gasket sealer should only be used on non-coated steel gaskets.

An exhaust leak can be frustrating. While exhaust leaks are often difficult to identify, worn exhaust manifold gaskets are often the problem. Removing worn exhaust manifold gaskets and replacing them with new gaskets on a Buick LeSabre is a small, inexpensive project for a do-it-yourself mechanic. With a few tools and a bit of time, you can remove failing exhaust manifold gaskets and replace them with new gaskets to increase the performance of your Buick LeSabre.

Instructions

1

Allow the engine and exhaust manifold to completely cool.

2

Disconnect any tubing from the exhaust manifold.

3

Loosen and remove the exhaust manifold bolts. If the bolts are resistant, use a penetrating oil to loosen them.

4

Remove the exhaust manifold and gaskets from the engine. The exhaust manifold in a Buick LeSabre is typically secured with two studs and two nuts.

5

Clean the gasket areas on both the engine and exhaust manifold with a scraper and wire brush to remove any remaining material from the old gasket. A clean, smooth surface ensures proper installation of the new gaskets.

The Sebring was first introduced to the North American market in 1995. It is a middle-size car manufactured by Chrysler. The 2001 model could be purchased as a coupe or a sedan. It was packed with a lot of features, including an ABS braking system, airbags and CD player. Like any car, the Sebring should be inspected and serviced periodically. If the head gasket in your 01 Sebring needs replacing, you can do the job if you have mechanical experience, the right tools, and access to a hoist.

Instructions

Removal Procedure

1

Disconnect the negative cable of your Sebrings battery. Remove the nut from the negative post with a box-end wrench. Lift the cable from your battery, move it outside of the battery box, and close the lid of the battery box.

2

Drain the antifreeze from the cooling system. Remove the throttle body air inlet hose and the air cleaner housing assembly. Take out the intake manifold. Disconnect the heater hose from the thermostat housing. Pull out the heater tube support bracket from the cylinder head.

3

Unplug the camshaft position sensor (CPS) electrical connector, then unplug the exhaust gas recirculation (EGR) valve electrical connector. Raise the vehicle on the hoist.

4

Disconnect the exhaust pipe from the exhaust manifold. Remove the accessory drive belts. Unscrew the crankshaft damper. Remove the upper and lower timing belt covers. Take off the timing belt. Remove the camshaft sprockets. Remove the timing belt idler pulley and the rear timing belt cover.

5

Lift the cylinder head cover. Take out the camshafts and rocker arms. Remove the cylinder head bolts using the torque wrench, then remove the cylinder head from the engine block.

6

Inspect and clean the cylinder head. The cylinder head must be flat within 0.004 inches. The cylinder head bolts should also be examined before reuse. If the threads are necked down, the bolts must be replaced. To ensure that the engine gasket is properly sealing, proper surface preparation must be performed, especially with aluminum engine components and multi-layer steel cylinder head gaskets.

Installation Procedure

7

Lay the cylinder head gasket on the block. Before installing the bolts, the threads should be coated with engine oil.

8

Install the cylinder head on the block. Tighten the cylinder head bolts using the 4-step torque turn method. In the first step, tighten all the bolts to 25 foot-pounds. In the second step, tighten all the bolts to 50 foot-pounds. In the third, tighten the cylinder head bolts again to 50 foot-pounds. In the final step, make an additional one-quarter of the turn with the torque wrench.

9

Install the rocker arms and camshafts. Replace the cylinder head cover. Install the rear timing belt cover and timing belt idler pulley. Install the camshaft sprockets. Install the timing belt.

10

Replace the upper and the lower timing belt covers. Install the crankshaft damper, then install the accessory drive belts. Connect the exhaust pipe to the exhaust manifold. Torque the fasteners to 250 inch-pounds.

11

Plug in the camshaft position sensor (CMS) electrical connector. Connect the EGR valve electrical connector. Install the heater tube support bracket to the cylinder head. Connect the heater hose to the thermostat housing. Install the intake manifold. Connect the throttle body air inlet hose and air cleaner housing assembly. Fill the cooling system.

Cummins diesel engines are a common engine option in full-size Dodge trucks. The six-cylinder, 5.9-liter Cummins engine has four valves per cylinder for a total of 24 valves. The gasket between the cylinder head and the engine block forms a tight seal between these two components. A leaking head gasket can cause the oil in the vehicle to have a milky appearance when it becomes contaminated by coolant.

Instructions

1

Place a clean container beneath the radiator, and open the drain cock with a socket wrench. Allow the coolant to drain into the pan, and save the coolant for reuse. Disconnect the cable from the negative battery terminal so you dont start the engine during the procedure.

2

Detach the accessory drive belt from its pulleys, and remove the alternator from the engine compartment with a socket wrench. Disconnect the air cleaner from the intake manifold. Remove the crankcase ventilation system and evaporative emissions system from the engine.

3

Remove the fuel lines from the fuel rail with a socket wrench. Disconnect the cables for the accelerator, cruise control and transmission to obtain access to the intake manifold. Remove the distributor cap with the electrical wiring still attached, and detach the electrical wiring from the ignition coil.

4

Detach the electrical connector from the engine coolant temperature sensor. Disconnect the water bypass hose and upper radiator hose from the engine to access the intake manifold. Remove the intake manifold and valve covers from the engine with a socket wrench.

5

Record the original position of the valve train components, including the rocker arms, push rods, exhaust manifolds and spark plugs. This ensures you can install these components in the correct position later. Remove the valve train components from the engine with a socket wrench.

6

Remove the mounting bolts for the cylinder head, and lift the cylinder heads from the engine block. Discard the gasket on the engine block.

7

Turn the crankshaft clockwise so that the timing marks for the crankshaft and camshaft do not align. This ensures that no piston is in the top dead center position when you install the cylinder head. Wait five minutes for the lash adjusters to depressurize before installing the cylinder head.

8

Place a new cylinder head gasket on the engine block, and mount the cylinder head on top of the gasket. Tighten the mounting bolts for the cylinder head to 50 foot-pounds with a torque wrench on the first pass and 105 foot-pounds on the second pass.

9

Install the valve train components to their original positions, using the notes you made in step five as a guide. Replace the additional components you removed to access the cylinder head by performing steps two through four in reverse.

10

Connect the cable for the negative battery terminal, and replace the coolant in the cooling system. Start the engine and check for fluid leaks.