Abstract:
A method and apparatus of repairing an automotive coolant pipe for fluid-conducting within an engine block of an engine, comprising a repair insert tube coated with a sealant, having a proximal proportion configuration for at least partially sealing an internal sealing ring or gasket, whereby the insertion of the repair insert tube coated with sealant will at least partially seal a leaking sealing ring or gasket within the engine block of the effected automobile.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    The present Application is related to Provisional Patent Application entitled “Automotive engine coolant pipe repair apparatus and method,” filed 15 Oct. 2013 and assigned filing No. 61/891,113, incorporated herein by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to automotive repair methods and components, and, more particularly, to a method of repairing an automotive engine cooling pipe leaking within an engine block. 
       BACKGROUND OF THE INVENTION 
       [0003]    An automotive engine cooling system plays a critical role for the continued optimum performance of the automobile engine. During the operation of an automobile, the combustion process causes a tremendous increase in the engine temperature. If not dissipated expeditiously and effectively, the excessive heat can severely damage the engine. Temperatures in the combustion chamber of the engine can reach 4,500° F. (2,500° C.). If the engine goes without cooling for very long, it can seize. When this happens, the metal would actually have gotten hot enough for the piston to weld itself to the cylinder. This usually means the complete destruction of the engine. The automotive engine cooling system handles the task of dissipating this excessive heat. An automotive engine cooling system basically consists of a radiator, a thermostat, a coolant tank, liquid coolant, a water pump, a radiator fan, and coolant transfer hoses and pipes. 
         [0004]    In a typical fuel-powered automobile, the thermostat sits between the engine and the radiator. The function of the thermostat is to block the flow of coolant to the radiator until the engine has warmed up sufficiently. When the engine is cold, no coolant flows through the engine. Once the engine reaches its operating temperature (generally about 200 degrees F., 95 degrees C.), the thermostat opens to enable the engine to warm up as quickly as possible. The thermostat thus reduces engine wear, deposits, and emissions. 
         [0005]    A coolant formulation is a mixture of an antifreeze and water, usually in the ratio of 1:1. The antifreeze in the coolant mixture reduces the freezing point and elevates the boiling point of the water in the mixture. The coolant is circulated throughout the engine through pipes and hoses by the water pump. The function of the coolant is to extract the excessive heat generated in the combustion chamber of the engine and transfer it to the radiator for dissipation. 
         [0006]    Hot coolant from the engine is transferred to the radiator and cooler coolant is transfer to the engine by heavy-duty hoses. A radiator is a type of heat exchanger. The radiator is designed to transfer heat from the hot coolant that flows through it to the air blown through it by the radiator fan. 
         [0007]    All automobiles are provided with an effective engine cooling system. Many automobile engines contain coolant transfer pipes within the engine block. However, very often, there are complaints of vehicles stalling due to engine over-heating caused by inadequate heat-dissipation, which in turn, is caused due to inadequacy or absence of coolant. Such an inadequacy or absence of coolant is invariably due to its leakage from the coolant supply pipeshoses owing to either cracks, cuts or holes therein or wear and tear of the seals lining the outer side of the ends of these pipeshoses at the point of joining a groove, socket or a receptacle at either end. 
         [0008]    One example of a leaking front seal on a coolant transfer pipe can be found on the BMW V-8 N62 engine. This engine has a common problem that is very expensive to repair. This BMW N62 Engine was used from 2002 through 2010 in vehicles including the BMW 735i, 740i, 745i, 745Li, 750i, 750Li. 645Ci, 650i, 545i, 550i, the X5 SUV and more. When BMW originally built the N62 engine at the factory, the coolant transfer pipe (part no. 11 14 1 439 975) was installed through the front of the engine block, before the installation of the timing chain cover. However, once the engine is installed in the vehicle, it is very expensive to remove the timing chain cover in order to install a new, factory-made BMW Coolant Transfer Pipe through the front of the engine. This repair job is conservatively estimated to cost anywhere between USD 7000 to USD 9000, and may take about two to three weeks of time. 
         [0009]    A second method was later developed, which involves accessing the coolant transfer pipe by removing the intake manifold. Once the intake manifold has been removed, then the existing coolant transfer pipe can be cut-out of the inside of the engine block, and a new collapsible coolant transfer pipe can be installed in place. Several companies manufacture these Collapsible Coolant Transfer Pipes. This is the most commonly-used method of repairing a leaking coolant transfer pipe because it is cheaper and faster to remove the intake manifold, than the original factory method of removing the Timing Chain Cover. 
         [0010]      FIGS. 1 and 2  show a replacement coolant transfer pipe  10  that is marketed by All German Auto as “the expanding cooling pipe,” in accordance with the disclosure in U.S. Pat. No. 8,464,424. The expanding cooling pipe is shown as being installed in the engine block of a BMW automobile having an N62 engine. Installation of the replacement coolant transfer pipe  10  is similar to that of the installation method for the collapsible BMW coolant transfer pipe, described above. Installation of the replacement coolant transfer pipe  10  also requires the removal of the intake manifold, and then requires cutting out the old coolant transfer pipe inside the engine block before the replacement coolant transfer pipe  10  can be installed. 
         [0011]    However, unlike the BMW coolant transfer pipe, which is a two-piece ensemble, the expanding cooling pipe  10  is a single expandable pipe. The expanding cooling pipe  10  comprises a front tube  12  having: (i) a proximal portion configured for at least partially slidably and sealably engaging a front sealing ring  14  seated within a front opening of the engine block, and (ii) a rear tube  16  telescopically engaged with the front tube  12 . The expanding cooling pipe  10  has a distal portion configured for at least partially slidably seating within a rear opening  18  of the engine block, whereby expansion of the cooling pipe apparatus within the engine block seats the proximal and distal portions of the front and rear tubes within the respective front and rear openings of the engine block. This feature provides sliding and rotational resistance to thereby stabilize the installation of the cooling pipe apparatus within the engine block. 
         [0012]    Bavarian Motor Parts (BMP) markets its own in-house designed collapsible BMW coolant transfer pipe  20  (Part No. 107914) as illustrated in  FIGS. 3A   3 E. This is a two-piece ensemble that contains; (i) a front inner tube  22  provided with machined o-ring grooves  24  on the outer surface to be fitted with seals and (ii) a rear outer tube  26 . The rear outer tube  26  has an inner diameter larger than or equal to the outer diameter of the front inner tube. The rear outer tube  26  also has a hollow protrusion  28  at one end whose outer diameter is smaller than the inner diameter of the front inner tube  22 . The outer tube  26  is fitted to the inner tube  22  by rotating the protruding part  28  of the outer tube  26  into the inner tube  22 . The fitting is packed with a nylon angled packing piece  30  to achieve a tight fit. The ends of the resultant pipe are then fitted to the corresponding receptacles  14 ,  18  in the engine block. 
         [0013]    The problem with both of these methods is that the front seal on both the factory installed coolant transfer pipe  10 , and the after-market collapsible transfer pipe  20  could eventually leak at the same place again after installation. 
         [0014]    Korean Patent publication KR 100143619 of Daewoo Motor Co. LTD., illustrated in  FIG. 4 , discloses a pipe fitting  32  wherein a projecting part of a first pipe  34  can be inserted into a second pipe  36 . The joined portion is coupled with the fitting  32  to prevent a coolant from leaking through the gap between the first pipe  34  and the second pipe  36 . However, this arrangement involves a plurality of parts and is only as good as the integrity of the coupling. Compression and expansion can affect the integrity of the coupling. Also, such an arrangement cannot prevent coolant leakage at the front seal. 
         [0015]    A GoWesty coolant pipe repair kit, illustrated in  FIG. 5 , provides a collection  40  of Brass fittings, screw clamps and spring clamps. However, these are suited only for repairing radiator coolant pipes located outside the engine block in Vanagons. 
         [0016]    The present invention provides a simpler, cost-effective and timesaving solution. A repair tube insert offers a more durable method of repairing a leaking front seal on a coolant transfer pipe that is also much less expensive to install. Through the unique repair apparatus and the method of repair disclosed herein, the present invention provides an inexpensive, time saving and simple solution to correct a failure of the front seal of a coolant transfer pipe in an automotive engine, the failure causing the engine to overheat from leakage of coolant. 
       BRIEF SUMMARY OF THE INVENTION 
       [0017]    In one aspect of the present invention, a method of repairing and stopping the leakage of coolant at the front seal in a coolant transfer pipe in the engine block of a vehicle method comprises: draining the coolant from the engine block; removing parts to access the inside of the coolant transfer pipe; installing a repair tube insert, with a component creating a seal, inside of the coolant transfer pipe; and re-assembling the engine and adding coolant. 
         [0018]    The additional features and advantage of the disclosed invention is set forth in the detailed description which follows, and will be apparent to those skilled in the art from the description or recognized by practicing the invention as described, together with the claims and appended drawings. 
     
    
     
       BRIEF DESCRIPTIONS OF THE DRAWINGS 
         [0019]    The foregoing aspects, uses, and advantages of the present invention will be more fully appreciated as the same becomes better understood from the following detailed description of the present invention when viewed in conjunction with the accompanying figures, in which: 
           [0020]      FIG. 1  is an illustration of the manner in which an expanding cooling pipe is installed in the engine block of a BMW car having an N62 engine, in accordance with the prior art; 
           [0021]      FIG. 2  shows the expanding cooling pipe of  FIG. 1  installed in the engine block; 
           [0022]      FIGS. 3A-3E  illustrate components provided in a BMP Design Collapsible BMW Coolant Transfer Pipe kit, in accordance with the prior art; 
           [0023]      FIG. 4  is an illustration of a pipe fitting disclosed by Korean patent KR100143619 issued to Daewoo Motors, in accordance with the prior art; 
           [0024]      FIG. 5  is an illustration of components of a coolant pipe repair kit available from GoWesty, in accordance with the prior art; 
           [0025]      FIG. 6  is a cross sectional view of a conventional engine block, in accordance with the prior art; 
           [0026]      FIG. 7  is a view of the conventional engine block of  FIG. 6  illustrating an apparatus and method for repairing a leaking front seal and coolant transfer pipe, in accordance with the present invention; 
           [0027]      FIG. 8  is a front view of the conventional engine block of  FIG. 7  with a water pump installed, in accordance with the present invention; 
           [0028]      FIG. 9  is a front view of the conventional engine block of  FIG. 7  with the water pump removed; 
           [0029]      FIGS. 10A-10C  illustrate repair kit components, including a sanding rod, a cleaning rod and an sponge applicator brush, in accordance with the present invention; and 
           [0030]      FIGS. 11A-11I  illustrate various embodiments of repair tube inserts, in accordance with the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0031]    The following detailed description is of the best currently contemplated modes of carrying out the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention. 
         [0032]    The present invention relates generally to an apparatus and method of repairing an internal coolant leak that can develop in engines that contain coolant transfer pipes within the engine block. An example of this type of coolant transfer pipe can be found in the “N62” engine, which is made by Bavarian Motor Works (BMW). In the BMW example, the coolant transfer pipe, (BMW part no. 11-14-1-339-975) tends to develop a leak around a front seal ring that is glued to the lip of BMW&#39;s transfer pipe. Over time, this glue can fail, causing BMW&#39;s front seal ring to separate from the transfer pipe. 
         [0033]    This defective part causes internal coolant to leak within the inside of the engine block itself, and the coolant then overflows out of the engine block through an exit small hole drilled in the engine. When the engine loses coolant, the engine will overheat and could cause major engine damage. In order to repair this problem, many hours of expensive shop labor and materials are required to remove major engine components such as the intake manifold and/or the timing cover, in order to gain access the defective Coolant Transfer Pipe and faulty Front Seal. 
         [0034]    The present invention teaches an apparatus and method for repairing the internal engine coolant leak without the requirement or extra steps of removing the intake manifold and/or the timing cover. This invention requires only the removal of the water pump, in order to gain access to the coolant transfer pipe. Once the water pump has been removed, access to the inside of the failed coolant transfer pipe and front seal is created. This newly created access makes it possible to repair the leaking coolant transfer pipe and front seal ring by sliding a repair tube insert coated with sealant, inside the failed coolant transfer pipe and front seal. 
         [0035]    The repair method disclosed in the present invention is exceptionally durable as the repair method utilizes components of high-strength aluminum alloy similar to the alloy used for manufacturing the engine. The repair method provides a metal liner and bonds to a coolant transfer and timing chain cover, using a special high-temperature coolant pipe silicon sealant. The sealant can be continuously immersed in antifreeze, and can withstand temperatures up to 500° C. The labor required to complete the disclosed repair method is usually only about one hour longer than the amount of shop time required to replace a water pump. 
         [0036]      FIG. 6  shows the side view of a crosscut section of a typical engine block  50 . This drawing illustrates a typical configuration for a BMW “N62” engine, but other engine configurations will still be within the teachings of this apparatus and method disclosure herein. During normal engine operation, the water pump  58  pumps coolant through the engine block  50 , first from the water pump  58 , through a timing cover coolant passage  56  in the timing cover  54 , then past the front seal  64 , and into the coolant transfer pipe  62 . In some cases, there can also be some leaking from a rear O-ring Seal  66 . 
         [0037]    When a front seal  64  fails, coolant will escape between the front seal  64  and the coolant transfer pipe  62 , causing the engine to become overheated and risk potential costly damage to the engine, and the potential for passengers of the vehicle to become stranded on the side of the road. In order to replace the coolant transfer pipe  62  and front seal  64 , a mechanic would need to remove the intake manifold  52  and/or the timing cover  54 , in order to remove the defective parts. 
         [0038]      FIG. 7  shows a unique apparatus and method for repairing the leaking front seal  64  and coolant transfer pipe  62 , without the need to remove the intake manifold  52  or the timing cover  54 , thereby saving many hours of expensive labor and costly parts and materials. After removing the water pump  58 , a repair tube insert  72  may be coated with sealant  74  and inserted through the timing cover coolant passage  56  directly into the coolant transfer pipe  62 . 
         [0039]    The repair tube insert  72  when coated with sealant  74  creates a bond and seal between the timing cover coolant passage  56 , the coolant transfer pipe  62  and the front seal  64 , in order to stop coolant from leaking into the engine block  50 . The original front seal  64  and the coolant transfer pipe  62  do not need to be removed from the engine block  50 , and remain in place. 
         [0040]      FIG. 8  shown a front view of a typical vehicle engine with a water pump  58 , an intake manifold  52 , a timing cover  54  and engine block  50 .  FIG. 9  shows the vehicle engine of  FIG. 8  with the water pump  58  removed to provide access to the timing cover coolant passage  56 . This access makes it possible to clean the inside walls of the timing cover coolant passage  56  and, as shown in  FIG. 7 , the front seal  64  and the coolant transfer pipe  62 . 
         [0041]    Once the inside walls of the surfaces are clean of any residual coolant or possible protrusions caused by the defective front seal  64  deformations, then the inside walls of these three surfaces can be coated with sealant  74 . The outside walls of the repair tube insert  72  may also be coated with the sealant  74 . Finally, the repair tube Insert  72  is inserted through the time cover coolant passage  56 , front seal  64  and coolant transfer pipe  62 . This procedure creates a substantially coolant tight seal when the sealant  74  is fully cured. 
         [0042]    It can be appreciated that the automotive engine cooling system repair apparatus and method of the present invention addresses the afore-described problem of leakage of coolant at the front seal in a coolant transfer pipe, and others by essentially providing an open ended, hollow repair tube insert  72  that is coated with sealant  74 . The repair tube insert  72  coated with the sealant  74  is inserted into the luminal passage that is formed by the timing chain cover coolant passage  56 ; the defective front seal  64 ; and the coolant transfer pipe  62 , in the engine block  50  of an automobile, and is placed approximately half way between the timing cover coolant passage  56  and the coolant transfer pipe  62 , and is centered within the defective front seal  64 . 
         [0043]    Once the sealant  74  dries and cures, the sealant  74  forms a watertight seal between the repair tube insert  72 , the coolant transfer pipe  62 , the front seal  64 , and the timing cover coolant passage  56 . This entire procedure requires just the removal of the water pump  58  to gain access to the timing chain cover, failed coolant transfer pipe  62  and the defective front seal  64 . 
         [0044]    In accordance with an exemplary embodiment, the disclosed hollow, open ended, sealant-coated repair tube  72  insert that snugly sits at the desired portion of the luminal passage  56  formed by the timing chain cover coolant passage  56 ; the defective front seal  64 ; and the coolant transfer pipe  62 , in the engine block  50  of an automobile, effectively seals off leakage at the defective front seal  64  without blocking the regular passage and flow of coolant through the luminal passage. 
         [0045]    The disclosed method can save the user many hours of labor and expense. The repair can also be done by some skilled do-it-yourself vehicle owner, because the repair job does not require removing major parts of the engine. In addition, the shortened repair time will help the owner of the affected vehicle to get his vehicle back from the repair shop much faster, so the owner will not need to borrow or rent a vehicle for an extended period. 
         [0046]    The repair kit or apparatus disclosed herein comprises at least one open ended, hollow repair tube insert or stent  72   72 , at least one cleaning rod, at least one sanding rod, sponge applicator brushes, at least one pair of rubber work gloves, pairs of disposable rubber gloves, at least one tube or pack of coolant pipe repair sealant, at least one bottle or jar of cooling system sealer cum coolant pipe O-ring conditioner, and detailed written instructions with illustrations. The cooling system sealer and conditioner are optional, as it is not necessarily required to achieve the objective of the present invention. The cooling system sealer and conditioner is not required to stop the “weep hole” leak from the front seal on the coolant transfer pipe. The front seal leak is repaired by the stent  72 . However, the cooling system sealer cum coolant pipe O-ring conditioner, is designed to condition the seals of the coolant transfer pipe, valley pan and gasket, as well as the gaskets of the rear coolant passage cover. 
         [0047]    The repair tube insert  72  outside diameter (OD) will be slightly smaller than the inside diameter (ID) of the coolant transfer pipe  62  and timing cover coolant passage  56 , so that when the repair tube insert is “dry fitted” (i.e., without sealant  74  in place), it is a snug fit as the repair tube insert  72  is inserted through the timing cover coolant passage  56 . 
         [0048]    The repair tube insert  72  may be constructed of a variety of alloys or rigged materials or semi-rigged materials, or non-rigged materials, including, but not limited to, metal, plastic, poly vinyl chloride (PVC), ceramic, fiberglass, rubber, silicone, adhesive tape, composites and other forms of rigged, semi-rigged and non-rigged materials. 
         [0049]    The sealant  74  may be a silicon-containing product or silicone based material, epoxy based material, petroleum based product, or any other material or gasket that will provide a watertight seal between the repair tube insert  72 , the coolant transfer pipe  62 , the front seal  64 , and the timing cover coolant passage  56 . The repair tube insert  72  or “stent  72 ” of the preferred embodiment of the present invention is an open ended, hollow cylindrical tube with circular ends.  FIG. 11A  illustrates the structure of the stent  72 . In an exemplary embodiment, the stent  72  is approximately five inches in length and has an outer diameter of about 1¼ inches. 
         [0050]    The repair procedure, which is common for all embodiments of the present invention with logical variations, additional or fewer steps that are apparent to a person skilled in the art, involves the following steps:
       1. Draining the coolant from the vehicle.   2. Removing the water pump  58  from the engine block  50 .   3. Elevating the front of the vehicle, so that any remaining coolant in the coolant transfer pipe  62  drains to the back of the engine block  50 , and the remaining coolant does not interfere with the application of the sealant  74 .   4. Inspecting for detecting the defective front seal  64  within the timing cover coolant passage  62  by using fingers to feel for the same. In some cases, where the defective front seal  64  might be protruding into the timing cover coolant passage  62 , an inspection mirror or camera may also be used to inspect the inside of the timing cover coolant passage  62  and front seal  64 . Cutting away any protruding parts of the defective front seal  64 , if required with a knife, so that the defective front seal  64  does not block or interfere with the insertion of the repair tube insert  72  during a “dry fit” test.   5. Drying, cleaning and sanding the inside of the timing cover coolant passage  56  and the coolant transfer pipe  62 , once the repair tube insert  72  fits snuggly into the timing cover coolant passage  62 , in order to create a dry and clean surface. Applying the sealant  74 , using a brush or fingers, onto the first few inches (approximately five inches) of the inner sidewalls of the timing cover coolant passage  56 , coolant transfer pipe  62  and defective front seal  64 .   6. Coating the outside walls of the repair tube insert  72  with the sealant  74 . In the case of a N62 engine repair example, the repair tube insert  72  is approximately 5 inches in length, and approximately 1¼ inches in outer diameter. Inserting the coated repair tube insert  72  into the timing cover coolant passage  56  and coolant transfer pipe  62 , so that the repair tube insert  72  is approximately half way between the timing cover coolant passage  56  and the coolant transfer pipe  62 , and is centered within the defective front seal  64 .  FIG. 7  provides an illustration for the proper placement of the repair insert tube  72  and removing any excess sealant  74 .   7. Finally, allowing the sealant  74  to fully cure. Once the sealant is fully cured, the water pump  58  can be re-installed, and the vehicle can be re-assembled.       
 
         [0058]    The sealant is resistant to, insoluble in or immiscible with water, antifreeze and any mixture thereof. Therefore, once the sealant, which is present in the narrow space between the stent  72   72  and the inner walls of the coolant transfer pipe  62 , timing cover coolant passage  56  and the front seal or its remnant, is fully cured, it provides a watertight seal between the repair tube insert  72 , the coolant transfer pipe  62 , the front seal  64 , and the timing cover coolant passage  56 . 
         [0059]    It is to be understood, however, that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure or manner. Even the apparatus and the corresponding method of any of the embodiments of the present invention may be applied by any person skilled in the art to any other system or setting, like the cooling system of a different vehicle, as applicable. 
         [0060]    The preferred embodiment of the present invention is designed to stop the leakage of coolant at the front seal  64  in the coolant transfer pipe in 4.4 litre and 4.8 litre V-8 N62 engine BMW cars. This includes the BMW 545i, 550i, 645Ci, 650i, 745i, 750i, the X5 SUV and more. The BMW Coolant Pipe Repair System, the preferred embodiment of the present invention, comprises the following:
       1. One repair tube insert or stent  72  (repairs front coolant pipe seal leak);   2. One tube of coolant pipe repair sealant  74 ;   3. One bottle of cooling system sealer cum coolant pipe O-ring conditioner;   4. One round sanding rod  82 ;   5. One round cleaning rod  84 ;   6. Six sponge applicator brushes  86 ;   7. One pair of rubber work gloves;   8. Four pairs of disposable rubber gloves; and   9. Detailed written instructions with systematic procedure illustrated with color photographs.       
 
         [0070]    The steps required to perform the repair procedure disclosed by the present embodiment include:
       1. Removing expansion tank cap from the coolant expansion tank when the engine is cool to avoid burns;   2. Removing front splashguard (if equipped) to access the radiator drain valve;   3. Opening the radiator drain valve, located at the bottom of the radiator on the right hand side and collecting the coolant in a container when the radiator drain valve is opened;   4. Draining, collecting and recycling coolant from the radiator;   5. Raising the front of the vehicle approximately four inches to ensure that any remaining coolant in the engine drains to the backside of the engine block, and does not interfere with the repair process;   6. Removing the fan cover;   7. Removing the engine cover;   8. Removing fresh air intake duct between air filter box and intake manifold;   9. Removing the fan clutch;   10. Removing the drive belt;   11. Removing the sensor plug connections and water pump pulley. Removing vacuum hoses, coolant hoses, and sensor attachments as needed to access the water pump. Unlocking and detaching all coolant hoses on water pump. Releasing screws and removing belt pulley;   12. Removing air conditioner compressor belt by releasing tension on the lower fan belt tensioner using a Torx wrench;   13. Removing lower crank case pulley in order to gain access to all the water pump bolts ensuring that only the eight Torx bolts attaching the crank case pulley are removed and the large bolt in the center of the lower crank case pulley stays in place, and is not loosened or removed;   14. Releasing water pump bolts and removing water pump;   15. Inspecting the coolant transfer pipe using the index finger for obstructions caused by the faulty front seal;   16. Cutting out, with a knife, any obstructions caused by the old coolant transfer pipe seal. Cutting away any small pieces of the old seal that may be sticking-out into the pipe and then removing any loose debris remaining in the coolant transfer pipe after the cutting taking care not to remove the entire old seal;   17. Sanding down a metal bump called a “casting mark” to ensure that the new stent  72  fits into place without any obstruction;   18. Sanding the insides of the coolant transfer pipe using the sanding rod such that the surfaces are “roughed-up” and cleaned of any coolant residue to ensure proper bonding of the stent  72  and sealant to the coolant transfer pipe and the timing chain cover. It is recommended to elevate the front of the vehicle slightly, so that any residual coolant in the coolant transfer pipe drains to the back of the engine block, and does not interfere with the sealing process. If a large casting mark bump is present, then a small electric grinder, such as a drill or a dermal tool, may be used to speed-up the sanding process.   19. Cleaning the inside surfaces of the timing chain cover and coolant transfer pipe in preparation for applying the sealant. A shop vacuum may be used to remove any loose material and antifreeze that may be in the coolant transfer pipe. The cleaning rod may be sprayed with brake parts cleaner to ensure that the inside of the timing chain cover and the coolant transfer pipe are as clean and dry as possible before applying the coolant pipe sealant.   20. “Dry-fitting” the stent  72  into the timing chain cover and coolant transfer pipe such that the stent  72  is able to slide in and out freely. Forcing-in the stent  72  is not recommended.   21. In case there is resistance, then additional cutting of the front seal, or sanding of the “casting mark, until the stent  72  fits in place and slides in-and-out, without becoming bound-up. Ensuring that the stent  72  is placed 1¼ inches inside of the flat water pump mounting surface;   22. Donning the rubber gloves, and getting the stent  72  and tube of coolant pipe repair sealant ready;   23. Removing the stent  72 ;   24. Squeezing the sealant onto the index finger;   25. Once the stent  72  has been removed, forcing the sealant into any gaps and crevices around the internal rubber front seal of the coolant transfer pipe. Appling sealant to the inner walls of the timing chain cover and coolant transfer pipe, so that the sealant sticks to the inner walls;   26. Applying the coolant pipe repair sealant to a sponge applicator brush  86 . Coating the inside passage of the timing chain cover and coolant transfer pipe with the coolant pipe repair sealant, ensuring that the sponge brush is not inserted past the “RED” mark  87  on the handle;   27. Coating the stent  72  with the sealant. Inserting the stent  72  into the timing chain cover and coolant transfer pipe. Rotating and turning the stent  72  slowly in a clockwise direction as the stent  72  is inserted. Stopping at the 1¼ inch mark.   28. Using a smart phone to photograph the insides of the coolant transfer pipe and to look very closely for possible obstructions of the pipe caused by excess sealant.   29. Ensuring that any blockage is removed from the coolant transfer pipe because it could cause overheating of the engine and result in engine damage;   30. Brushing, using a clean sponge, to remove any excess sealant immediately after installing the stent  72  in order to make sure that any blockage has been removed. Inserting the sponge brush all the way up to the “BLACK” mark  88  on the handle of the brush  86  during the cleaning process;   31. Taking additional photos of the stent  72  and the insides of the coolant transfer pipe and continuing to clean the pipe until it is totally free of any possible blockage.   32. Once the stent  72  is free of any possible blockage, allowing the stent  72  and sealant to dry for 24-hours before re-assembly and adding antifreeze.   33. Adding the cooling system sealer cum Coolant pipe O-ring Conditioner directly into the upper radiator hose before attaching the hose to the upper radiator outlet, during the re-assembly process;   34. Driving the vehicle for about 200 miles after re-assembly, for the cooling system sealer cum conditioner to fully condition and seal the engine block and cooling system. The cooling system sealer cum conditioner stays in the cooling system, and does not need to be removed after 200 miles.       
 
         [0105]    The repair tube inserts of the alternative embodiments of the present invention can have different shapes and geometry from that of the preferred embodiment of the present invention, depending on the geometry of the timing chain cover passage and the coolant transfer pipe against which the stent  72  is required to provide a leak-free seal and fit. In all the embodiments of the present invention, a stent  72  is basically an open ended, hollow, tube-like structure the shape and geometry of which may vary based on the geometry of the luminal passage that is formed by the timing chain cover coolant passage, the front seal and the coolant transfer pipe. 
         [0106]    The stent  72  of the present invention corresponds in shape to the geometry of the luminal passage that is formed by the timing chain cover coolant passage; the front seal; and the coolant transfer pipe, in the engine block of the automobile. Its outer dimensions are a little smaller than the inner dimensions of the aforementioned luminal passage, which allows the stent  72  to be comfortably placed at the desired portion of the luminal passage and ensures a sufficiently tight fit of the stent  72  in the luminal passage. The stent  72  of the present invention can have any shape, dimensions that enables it to be comfortably inserted and placed at the desired portion of the luminal passage, and ensures a sufficiently tight fit of the stent  72  in the luminal passage. 
         [0107]      FIG. 11B  illustrates the structure of an alternative configuration of a stent  92 , which is a hollow cuboidal open ended tube having rectangular ends with beveled edges.  FIG. 11C  illustrates the structure of a stent  94  configured as a hollow semi-tapered, open ended, cylindrical tube that evens out to a right circular cylinder at a certain point along its length. 
         [0108]      FIG. 11D  illustrates the structure of a stent  96  configured with circular ends, the stent  96  being a hollow tapering open ended cylindrical tube that evens out to a right circular cylinder at a certain point along its length.  FIG. 11E  illustrates the structure of another type of stent  98 , configured as a hollow tapering open ended cylindrical tube. This stent  98  can be used in a BMW N73 V-12 engine that requires a taper at one end of the stent  98  in order to create a better seal and fit against the timing chain cover. 
         [0109]      FIG. 11F  illustrates the structure of a stent  102 , which is a hollow semi-tapered open ended cylindrical tube.  FIG. 11G  illustrates the structure of a stent  104 , which is a hollow open ended oval tube having oval ends. 
         [0110]      FIG. 11H  illustrates the structure of a stent  106 , which is open ended; and half of which is a hollow right circular cylindrical tube  108  and the other half is a rectangular, hollow tube  110 . The circular cylindrical tube  108  may be inserted into a round coolant transfer pipe, and the rectangular, hollow tube  110  interfaces with a timing chain cover. This type of stent  106  can be used in a few models of Range Rover. 
         [0111]      FIG. 11I  illustrates the structure of a stent  112 , which is a hollow semi-cylindrical or semi-oval tube having semi-circular or semi-oval ends, as the case may be; has a flat flared bottom side and a tapering top side. There could be several other variations in the shape and geometry of the repair tube insert and all such embodiments would still be deemed to be within the scope and teachings of the present invention. 
         [0112]    It is to be understood that the description herein is only exemplary of the invention, and is intended to provide an overview for the understanding of the nature and character of the disclosed illumination systems. The accompanying drawings are included to provide a further understanding of various features and embodiments of the method and devices of the invention which, together with their description serve to explain the principles and operation of the invention.