Injector sleeve assembly and method for field repair process

Abstract

A retaining ring configured for field repair of an upper seal leak on a fuel injector sleeve, the retaining ring comprising: a circular sidewall comprising a barrel-shaped outer surface and a generally cylindrical inner surface; wherein the outer surface comprises a lower curved portion and a central portion having less pronounced curvature than the lower curved portion; and wherein the lower curved portion is configured to guide the retaining ring into the fuel injector sleeve, and the circular sidewall has an outer diameter at the central portion that is greater than an inner diameter of the fuel injector sleeve at a location of the upper seal leak, such that the retaining ring forces the fuel injector sleeve outward at the location of the upper seal leak as the retaining ring is moved into an installed position.

Description

[0001] Related applications

[0002] This application relates to and claims priority to U.S. Provisional Application No. 62 / 414996, filed October 31, 2016, entitled “INJECTOR SLEEVE ASSEMBLY ANDMETHOD FOR FIELD REPAIR PROCEDURE”, the entire disclosure of which is expressly incorporated herein by reference. Technical Field

[0003] The present invention relates generally to fuel injector sleeve seals, and more specifically to structures and methods for field repair of fuel injector sleeve leaks at the upper sealing location. Background Technology

[0004] Internal combustion engines with fuel injectors typically position the injectors in holes formed in the cylinder head. An injector sleeve is usually inserted into the injector hole, and the injector is received within the sleeve. One or more coolant chambers are formed in the cylinder head and separated from the injector by the injector sleeve. To prevent leakage of coolant and / or combustion gases, seals are typically formed between the sleeve and the cylinder holes located above and below the coolant chambers. In some cases, one or both seals are formed of an elastomeric material.

[0005] It is not uncommon for upper elastomer seals to deteriorate over time and require replacement. In the absence of authorized procedures, tool kits, or tools for performing seal replacement / repair at a refit facility or outside the original equipment manufacturer (OEM), the entire cylinder head often needs to be removed. This technique is expensive, labor-intensive, and requires significant engine downtime. In fact, the cost of a new or refitted cylinder head can exceed $4,000, and the labor (e.g., approximately 20 hours) can add another $2,000 to the overall cost. Alternatively, expensive aftermarket tool kits can be used to repair leaking injector sleeves by screwing in a plug and pulling the sleeve out of the cylinder head, then pressing in a new sleeve. This typically requires a sealing compound, applied either dry, pre-coated, or by using an additional sealant at the sleeve-to-cylinder head interface. This method is also expensive, time-consuming, and complex, and requires the removal of the entire injector sleeve. Therefore, it is desirable to provide a cheap, quick, and simple method for repairing leaking upper seals between injector sleeves and injector bores in the field. Summary of the Invention

[0006] In one embodiment, this disclosure provides a method for repairing a seal between a fuel injector sleeve and a fuel injector bore, the method comprising the steps of: removing a fuel injector from the fuel injector sleeve; installing a retaining ring in the fuel injector bore, the retaining ring having a sidewall having an outer surface having a bend adjacent to at least one edge to guide the retaining ring into the fuel injector bore, the retaining ring also having an outer diameter larger than the inner diameter of the fuel injector sleeve at a location adjacent to the seal, such that when the retaining ring is in the installed position, the fuel injector sleeve deforms outward toward the fuel injector bore, thereby repairing the seal; and replacing the fuel injector. In one aspect of this embodiment, installing the retaining ring includes placing the retaining ring on an insertion tool, inserting the insertion tool into the fuel injector sleeve, and using the insertion tool to force the retaining ring into its installed position. In a variation of this aspect, using an insertion tool to force the retaining ring into its mounting position includes rotating the drive rod of the insertion tool such that the engagement boss of the insertion tool forces the retaining ring into the fuel injector sleeve until a retaining nut mounted on the drive rod engages the upper surface of the insertion tool. In another variation, installing the retaining ring includes attaching the insertion tool to the cylinder head forming the fuel injector bore. In a further modification of this variation, attaching the insertion tool to the cylinder head includes positioning a mounting hole in the shank body of the insertion tool aligned with an opening in the cylinder head adjacent to the fuel injector bore, and screwing a cap screw into the opening through the mounting hole. In yet another modification, attaching the insertion tool to the cylinder head includes screwing a bolt into an opening through an extension of the shank body of the insertion tool, such that the foot of the bolt engages the surface of the cylinder head. In another aspect of this embodiment, the retaining ring includes an outer surface comprising at least one of an upper bend and a lower bend, and a central portion having a less pronounced curvature than the upper and lower bends, such that the outer surface resembles a barrel. In a variation of this aspect, installing the retaining ring includes centering the retaining ring within the fuel injector sleeve via at least one of its upper and lower bends. In another variation, the upper bend of the retaining ring is adjacent to a generally flat upper edge of the retaining ring, and the lower bend of the retaining ring is adjacent to a generally flat lower edge of the retaining ring. In yet another aspect, the outer diameter of the retaining ring is larger than the inner diameter of the fuel injector sleeve by a distance ranging from 0.3 to 0.6 mm. In a variation of this aspect, the outer diameter of the retaining ring is larger than the inner diameter of the fuel injector sleeve by a distance ranging from 0.35 to 0.5 mm.

[0007] In another embodiment, this disclosure provides a retaining ring configured for field repair of a sealing leak on a fuel injector sleeve, the retaining ring comprising: a circular sidewall including a barrel-shaped outer surface and a generally cylindrical inner surface; wherein the outer surface includes a downward bend and a central portion having a curvature less pronounced than the downward bend; and wherein the downward bend is configured to guide the retaining ring into the fuel injector sleeve, and the circular sidewall has an outer diameter at the central portion larger than the inner diameter of the fuel injector sleeve at the location of the upper sealing leak, such that as the retaining ring moves to an installation position, the retaining ring outwardly presses against the fuel injector sleeve at the location of the upper sealing leak. In one aspect of this embodiment, the circular sidewall includes an upper edge located between the inner and outer surfaces and a lower edge located between the inner and outer surfaces. In a variation of this aspect, the downward bend is adjacent to the lower edge of the circular sidewall. In another aspect, the circular sidewall defines a central opening having a generally constant diameter between the upper and lower edges of the circular sidewall. In yet another aspect, the outer surface also includes an upper bend adjacent to the upper edge. In another aspect, the outer diameter at the center of the retaining ring is larger than the inner diameter of the fuel injector sleeve by a distance ranging from 0.3 to 0.6 mm. In a variant of this aspect, the outer diameter at the center of the retaining ring is larger than the inner diameter of the fuel injector sleeve by a distance ranging from 0.35 to 0.5 mm.

[0008] In another embodiment, this disclosure provides a system for field repair of a sealing leak on a fuel injector sleeve, the system comprising: a retaining ring including a circular sidewall having an outer surface defining a central opening, the outer surface including a lower portion configured to guide the retaining ring into the fuel injector sleeve and having a diameter larger than the inner diameter of the fuel injector sleeve adjacent to the upper sealing leak; and an insertion tool including a shank, a threaded drive rod coupled to the shank, and a guide end coupled to the threaded drive rod and configured to extend into the fuel injector sleeve, the shank including a mounting hole configured to receive a cap screw for mounting the insertion tool to an engine cylinder head, the threaded drive rod including a drive head, and the guide end configured to extend through the central opening of the retaining ring and having an engagement boss that, in response to rotation of the drive head, forces the retaining ring into a mounting position within the fuel injector sleeve when the shank is mounted to the cylinder head; wherein the outer surface of the retaining ring presses the fuel injector sleeve outwardly at the location of the upper sealing leak as the retaining ring is pressed into its mounting position. In one aspect of this embodiment, the central portion of the outer surface has a less pronounced curvature than the lower portion. In a variation of this aspect, the retaining ring further includes an upper portion having a more pronounced curvature than the central portion, making the outer surface resemble a barrel. In yet another aspect of this embodiment, the insertion tool handle includes an extension opposite the mounting hole, the extension including an opening for receiving a bolt that is coupled to a foot configured to engage a cylinder head.

[0009] While several embodiments have been disclosed, other embodiments of the invention will become apparent to those skilled in the art from the following detailed description, which illustrates and describes exemplary embodiments of the invention. Therefore, the drawings and detailed description are considered illustrative in nature and not limiting. Attached Figure Description

[0010] The foregoing and other features of this disclosure, and the ways in which they are obtained, will become clearer from the following description of embodiments of this disclosure taken in conjunction with the accompanying drawings, in which:

[0011] Figure 1 This is a cross-sectional view of the fuel injector assembly;

[0012] Figure 2 It is a cross-sectional view of a fuel injector assembly having a retaining ring, according to one embodiment of the present disclosure, which is installed to repair leaks in the upper seal of the fuel injector.

[0013] Figure 3A yes Figure 2 A three-dimensional view of the retaining ring;

[0014] Figure 3B yes Figure 2 Top view of the retaining ring;

[0015] Figure 3C yes Figure 2 A cross-sectional view of the retaining ring;

[0016] Figure 4 It is used for insertion Figure 2 A three-dimensional view of the insertion tool for the retaining ring;

[0017] Figure 5 yes Figure 4 Top view of the insertion tool;

[0018] Figure 6 It is used for installation Figure 2 The retaining ring Figure 4 A cross-sectional side view of the insertion tool;

[0019] Figure 7 It is used for insertion Figure 2 A perspective view of another embodiment of the insertion tool for the retaining ring;

[0020] Figure 8 yes Figure 7 The top view of the insertion tool; and

[0021] Figure 9 It is used for installation Figure 2 The retaining ring Figure 7 The side view of the insert tool in profile.

[0022] While this disclosure accepts various modifications and alternatives, specific embodiments are illustrated by way of example in the accompanying drawings and described in detail below. However, this disclosure is not intended to limit the particular embodiments described. Rather, this disclosure is intended to cover all modifications, equivalents, and substitutions that fall within the scope of the appended claims. Detailed Implementation

[0023] As used here, the modifier “approximately” in relation to quantity includes the stated value and has a meaning determined by the context (e.g., it includes at least the degree of error associated with the measurement of a particular quantity). When used in the context of range, the modifier “approximately” should also be considered to disclose the range defined by the absolute values ​​of the two endpoints. For example, the range “from approximately 2 to approximately 4” also discloses the range “from 2 to 4”.

[0024] This disclosure provides a field repair process and system that allows for the repair of leaking injector seals on elastomers (or other materials) without the need to remove the cylinder head or injector sleeve. As further described below, a retaining ring with a generally self-centering and self-guided barrel-shaped outer profile is installed in situ into the injector sleeve and is sized with an outer diameter larger than the inner diameter of the injector sleeve to create an interference fit that re-establishes sealing capability after a leak has formed. The retaining ring can be installed using a simple pressing or impact tool that extends into the cylinder bore to seat it to the appropriate depth. Using the process and system described herein, seals can be repaired at a minimal cost with significantly reduced engine downtime.

[0025] Now refer to Figure 1 A typical fuel injector assembly 10 is shown. Assembly 10 typically includes a fuel injector 12 disposed within an injector sleeve 14, which in turn is disposed within an injector bore 16 formed in a cylinder head 18. The cylinder head 18 includes a coolant passage 20 in fluid communication with the injector bore 16. A retaining ring 22 may be positioned in the lower portion of the sleeve 14 to provide a lower seal for the coolant passage 20 at an interface 24 having a bore sealing surface 26, as described in U.S. Patent No. 8,230,808 entitled *INJECTOR SEAL ASSEMBLY AND METHOD OF SEALING A COOLANT PASSAGE FROM ANINJECTOR*, which is also owned by the assignee and whose entire disclosure is expressly incorporated herein by reference. The sleeve 14 typically has a sidewall 29 having a cylindrical or tubular shape formed of a suitable material for sliding fit into a suitable position in the bore 16. At its upper end, the sleeve 14 typically includes an annular groove 28 for receiving a sealing ring 30, which may be made of an elastomeric material. In other embodiments, the sealing ring 30 and the annular groove 28 may be omitted, or replaced with a series of shallow grooves to enhance the plasticity of the sleeve's outer surface. In either case, the sleeve 14 is cut to a suitable diameter to create a tight fit and is then typically rolled using a conventional rolling mill to form a seal with a hole 16 and create a slight locking feature in the sleeve material into the coolant passage. This separates the coolant passage 20 from the annular cavity 32 located between the injector 12 and the sleeve 14, which is typically filled with low-pressure fuel. As shown, in a particular embodiment, the upper end of the sleeve 14 has a polished region 34.

[0026] Under certain conditions and / or over time, the sealing ring may deteriorate and leak. As indicated above, replacing / repairing the sealing ring 30 using conventional techniques can be expensive, time-consuming, and complex. This disclosure provides techniques and systems for field-based repair of the seal provided by the sealing ring 30 without removing the sleeve 14 or replacing the cylinder head 18. According to one embodiment of this disclosure, a retaining ring 36 is provided to repair the seal provided by the sealing ring 30. Typically, as... Figure 2 As shown, retaining ring 36 is positioned between fuel injector 12 and injector sleeve 14 to press sleeve 14 outward to repair the seal previously provided by damaged / deteriorated sealing ring 30.

[0027] Now refer to Figures 3A to 3C The retaining ring 36 is a generally circular sidewall 40 with a defined central opening 41. Figure 3A The retaining ring 40 is a generally annular component. The sidewall 40 includes a generally barrel-shaped outer surface 38 and a cylindrical inner surface 42 having a generally constant cross-section. The outer surface 38 includes a curved upper portion 44 and a curved lower portion 46 connected by a central portion 48 having a less pronounced curvature. The sidewall 40 also includes a generally flat upper edge 45 and a generally flat lower edge 47. A central opening 41 has a generally constant diameter 53 between the upper edge 45 and the lower edge 47 of the circular sidewall 40. In some embodiments, the retaining ring 36 is formed of steel, but other materials may be suitable in particular applications. As will be apparent from the description herein, the retaining ring 46 may be inserted first into the upper edge 45 of the sleeve 14 or first into the lower edge 47. In other embodiments, the retaining ring 46 includes only one of the curved upper portion 44 or the curved lower portion 46. In this embodiment, the edges 45, 47 corresponding to the provided bends must be installed first to allow for the guidance and self-centering described herein.

[0028] Because a typical injector sleeve 14 has little or no front chamfer along its upper edge, as further described below, during insertion, the lower portion 46 of the outer surface 38 allows the retaining ring 36 to be centered and guided into the installed position. At least at the center portion 48, the retaining ring 36 has a diameter 52 greater than the inner diameter 52 of the polished region 34 of the sleeve 14. Figure 2 The outer diameter 50 is larger. Because of this, the retaining ring 36 is inserted into the polished area 34 of the sleeve 14 (using a tool such as described below) to expand the sleeve 14 at the polished area 34, so that the sleeve 14 (with or without the elastomeric sealing ring 30) provides additional sealing pressure between the sleeve 14 and the bore 16 to prevent leakage and restore the previously provided seal. In one embodiment, the outer diameter 50 is larger than the inner diameter 52 by a distance in the range of 0.3 to 0.6 mm (more preferably in the range of 0.35 to 0.5 mm).

[0029] Now refer to Figure 4 The illustration depicts an example insertion tool 54 having a retaining ring 36 mounted for insertion into an injector sleeve 14. The tool 54 typically includes a shank 56, a threaded drive rod 58, and a guide end 60. The shank 56 includes: a body 62 having a mounting hole 64 extending between an upper side 66 and a lower side 68 of the body 62; and a drive end 70 having a boss 72. A threaded opening 74 extends through the drive end 70 and receives the drive rod 58. The drive rod 58 includes a threaded body 76 having a drive head 78 at one end and a rotatable coupling 79 at the end connected to the guide end 60. Figure 6 The guide end 60 has an upper engaging boss 80, a cylindrical body 82 sized to receive the retaining ring 36, and an end 84 configured to extend outward from the bottom within the injector orifice 16. As further described below, when the guide end 60 is fully inserted into the injector sleeve 14, the end 84 limits the insertion distance, and the engaging boss 80 positions the retaining ring 36 in the proper mounting position. Although Figure 6 An end 84 is shown that limits travel and controls the insertion depth of the retaining ring 36 upon contact with the cylinder head, but this feature is not necessary and can be replaced by a guide end 60 in other embodiments, which has a diameter slightly smaller than the injector orifice size and slightly larger than the injector sleeve diameter to limit travel upon contact with the upper edge face of the sleeve 14.

[0030] Now refer to Figure 5 and Figure 6 The retaining ring 36 is inserted into the sleeve 14 to repair the seal provided by the sealing ring 30 using the tool 54 in the following manner. After removing the injector clip (not shown), the fuel injector 12 is removed from the sleeve 14. The retaining ring 36 is placed onto the body 82 of the guide end 60 of the tool 54. The guide end 60 (with the retaining ring 36) is then inserted into the injector hole 16 and positioned downwards into the sleeve 14. The boss 72 of the drive end 70 of the handle 56 is positioned as follows: Figure 6The actuator 58 is positioned in the injector bore 16 to properly orient the actuator 58. A mounting hole 64 is positioned on the shank body 62 to align with a threaded opening 90 adjacent to the injector bore 16, which is typically used to receive bolts for attaching the injector lower clamp (not shown). The bolt 92 is passed through the mounting hole 64 and screwed into the opening 90 until the shank 56 is securely attached to the cylinder head 18. After securing the shank 56 (and thus the tool 54) to the cylinder head 18, the actuator head 78 of the actuator 58 is rotated using a tool such as a wrench, thereby forcing the guide end 60 downward into the sleeve 14. As the guide end 60 moves downward, the engagement boss 80 of the guide end 60 forces the retaining ring 36 into the sleeve 14. As the retaining ring 36 engages the upper edge of the sleeve 14, one of the bends 44, 46 of the outer surface 38 (depending on the orientation of the ring 36) guides and centers the retaining ring 36 into the sleeve 14. The drive head 78 is rotated further until the end 84 of the guide end 60 protrudes from the bottom within the injector hole 16. During this process, the retaining ring 36 is positioned at the appropriate depth in its mounting position within the sleeve 14, and it exerts a directional force outward relative to the greater outer diameter of the sleeve 14, which re-establishes the seal between the sleeve 14 and the hole 16 where the faulty sealing ring 30 is located. It should be understood that the retaining ring 36 can be removed from the sleeve 14 using a suitable tool that engages the lower edge (45 or 47) of the retaining ring 36 and applies an upward force to push the retaining ring 36 out of the sleeve 14.

[0031] Now refer to Figure 7 The image depicts another example insertion tool 154 for installing the retaining ring 36 into the injector sleeve 14. Figure 4 Like tool 54, tool 154 typically includes a shank 156, a threaded drive rod 158, and a guide end 160. The shank 156 includes: a body 162 having a mounting hole 164 extending between an upper side 166 and a lower side 168 of the body 162; and a drive end 170 having a boss 172. As described below, a cap screw 171 extends through the mounting hole 164 to attach tool 154 to cylinder head 18. A threaded opening 174 extends through drive end 170 and receives drive rod 158. Drive rod 158 includes a threaded body 176 having a drive head 178 at one end and a rotatable connection 179 at the end connected to guide end 160. Figure 9The guide end 160 has an upper engaging boss 180 and a cylindrical body 182 sized to receive the retaining ring 36. The drive rod 158 also includes a stop nut 184, which in one embodiment is attached in a fixed position on the threaded body 176 adjacent to the drive head 178. As illustrated herein, as the drive rod 158 is rotated using the drive head 178, the drive rod screws into the drive end 170 through the handle 156 and presses the retaining ring 36 into the injector orifice 16. The stop nut 184 can be positioned on the drive rod 158 to engage the upper surface 166 of the handle 156 to set the insertion depth of the retaining ring 36. In this way, the stop nut 184 provides a repeatable insertion depth of the retaining ring 36 and prevents over-tensioning or under-tensioning. In another embodiment, the stop nut 184 can be adjustablely positioned on the drive rod 158 to provide various different insertion depths.

[0032] The handle body 162 also includes a pair of forward recesses 186, 188, which are configured to, when the tool 154 is attached to the cylinder head 18, provide... Figure 8 The depicted valve spring provides clearance. The body 162 also has a pair of rearward recesses 190, 192, which are configured as follows: Figure 8 The cylinder head cap screws shown provide clearance. Finally, the shank body 162 includes an extension 194 with a threaded opening 196. A threaded bolt 198 extends through the opening 196 and pivotally connects to the foot 200. As further described here, the bolt 198 is used to tension the foot 200 to engage with the cylinder head 18 to balance the force applied when the drive rod 158 is screwed into the injector bore 16.

[0033] Now refer to Figure 8 and Figure 9 The retaining ring 36 is inserted into the sleeve 14 to repair the seal provided by the sealing ring 30 using the tool 154 in the following manner: After removing the injector clip (not shown), remove the fuel injector 12 from the sleeve 14. Place the retaining ring 36 onto the body 182 of the guide end 160 of the tool 154. Then insert the guide end 160 (with the retaining ring 36) into the injector hole 16 and position it downwards into the sleeve 14. Position the boss 172 of the drive end 170 of the shank 156 as follows... Figure 9 The actuator 158 is positioned in the injector bore 16 to properly orient the drive rod 158. A mounting hole 164 is positioned on the shank body 162 to align with a threaded opening 202 adjacent to the injector bore 16, which is typically used to receive bolts for attaching the injector lower clamp (not shown). A cap screw 171 is passed through the mounting hole 164 and screwed into the opening 202 until the shank 156 is securely attached to the cylinder head 18. The bolt 198 is then tightened to force the foot 200 into engagement with the cylinder head 18.

[0034] After securing the handle 156 (and therefore the tool 154) to the cylinder head 18 as described above, the drive head 178 of the drive rod 158 is rotated using a tool such as a wrench, thereby forcing the guide end 160 downward into the sleeve 14. As the guide end 160 moves downward, the engagement boss 180 of the guide end 160 forces the retaining ring 36 into the sleeve 14. As the retaining ring 36 engages the upper edge of the sleeve 14, one of the bends 44, 46 of the outer surface 38 (depending on the orientation of the ring 36) guides and centers the retaining ring 36 into the sleeve 14. The drive head 178 is further rotated until the stop nut 184 engages the upper surface 166 of the drive end 170. When this occurs, the retaining ring 36 is positioned at the appropriate depth in its installation position within the sleeve 14, and it exerts a directional force outward relative to the greater outer diameter of the sleeve 14, which re-establishes the seal between the sleeve 14 and the bore 16 where the faulty sealing ring 30 is located. It should be understood that the retaining ring 36 can be removed from the sleeve 14 using a suitable tool that engages the lower edge (45 or 47) of the retaining ring 36 and applies an upward force to pull the retaining ring 36 out of the sleeve 14.

[0035] As the drive rod 158 forces the retaining ring 36 downward into the sleeve 14, the reaction force points upward, approximately along... Figure 9 The force pushes the tool 154 in direction A. This force may damage the cap screw 171 or other components of the tool 154. In this embodiment, a similar reaction force is generated when the foot 200 of the extension 194 engages the cylinder head 18, which is approximately along... Figure 9 The force pushes the tool 154 in direction B. This reaction force is used to balance the force in direction A and to prevent damage to the tool 154. In this way, the life of the tool 154 is extended, allowing it to be reused to install multiple retaining rings 36.

[0036] It should also be understood that the principles described herein can also be used for the initial manufacturing assembly of fuel injector sleeves in the cylinder head. This would eliminate the need for polishing and the time associated with this operation. Moreover, in certain applications, it would eliminate the need for injector seals on the elastomer.

[0037] It should also be understood that the connecting lines shown in the various figures included herein are intended to represent exemplary functional relationships and / or physical connections between various elements. It should be noted that many alternative or additional functional relationships or physical connections may exist in the actual system. However, benefits, advantages, solutions to problems, and any elements that may cause any benefit, advantage, or solution to occur or become more significant are not to be construed as critical, desired, or necessary features or elements. The scope is therefore not limited to anything other than the appended claims, in which references to singular elements are not intended to mean “one and only one” unless explicitly stated otherwise, but rather to mean “one or more.” Moreover, where phrases similar to “at least one of A, B, or C” are used in the claims, it is contemplated that such phrases be interpreted as meaning that A alone may exist in an embodiment, B alone may exist in an embodiment, C alone may exist in an embodiment, or any combination of elements A, B, or C may exist in a single embodiment; for example, A and B, A and C, B and C, or A and B and C.

[0038] In the specific embodiments described herein, references to "one embodiment," "implementation," "example embodiment," etc., indicate that an embodiment may include a particular feature, structure, or characteristic, but each embodiment may not necessarily include that particular feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same embodiment. Further, when describing a particular feature, structure, or characteristic with respect to an embodiment, it is assumed that, whether explicitly described or not, it is within the knowledge of a person skilled in the art regarding the influence of other embodiments on that feature, structure, or characteristic, and which has the benefits of this disclosure. Upon reading this specification, it will become apparent to those skilled in the art how this disclosure may be implemented in alternative embodiments.

[0039] Furthermore, regardless of whether an element, component, or method step in this disclosure is expressly listed in the claims, it is not intended to be exclusive to the public. No element of any claim is to be construed as falling under the provisions of 35 U.S.SC112(f) unless it is expressly listed using the phrase “means for…”. As used herein, the term “comprising” or any variation thereof is intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements comprises not only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0040] Various modifications and additions may be made to the exemplary embodiments discussed without departing from the scope of this disclosure. For example, while specific features are mentioned in the above embodiments, the scope of this disclosure also includes embodiments having different combinations of features and embodiments that do not include all of the stated features. Therefore, the scope of this disclosure is intended to include all such substitutions, modifications, and variations, and all equivalents thereof, as falling within the scope of the claims.

Claims

1. A method for field repair of a fuel injector sleeve, the method comprising the steps of: removing a fuel injector from the fuel injector sleeve, the fuel injector sleeve having an upper portion and a lower portion; installing a retaining ring in a fuel injector bore, the retaining ring having a sidewall with an outer surface including a bend adjacent at least one edge of the sidewall to guide the retaining ring into the fuel injector bore, the retaining ring further having an outer diameter greater than an inner diameter of the upper portion of the fuel injector sleeve at a location adjacent an upper seal leak in the upper portion of the fuel injector sleeve such that the upper portion of the fuel injector sleeve is deformed outwardly toward the fuel injector bore when the retaining ring is in an installed position to thereby repair the upper seal leak; and replacing the fuel injector in the fuel injector sleeve, wherein installing the retaining ring includes placing the retaining ring on an insertion tool, inserting the insertion tool into the fuel injector sleeve, and using the insertion tool to force the retaining ring into the installed position, and wherein using the insertion tool to force the retaining ring into the installed position includes rotating a drive rod of the insertion tool such that an engagement boss of the insertion tool forces the retaining ring into the fuel injector sleeve until a stop nut mounted to the drive rod engages an upper surface of the insertion tool. Installing the retaining ring further includes attaching the insertion tool to a cylinder head that forms the fuel injector bore.

2. The method of claim 1, wherein, Attaching the insertion tool to the cylinder head includes:

3. The method of claim 2, wherein, positioning a mounting hole of a shank body of the insertion tool in alignment with an opening in the cylinder head adjacent the fuel injector bore; and screwing a cap screw through the mounting hole into the opening. Attaching the insertion tool to the cylinder head includes screwing a bolt through an opening in an extension of a shank body of the insertion tool such that a foot connected to the bolt engages a surface of the cylinder head thereby.

4. The method of claim 2, wherein, The bend of the outer surface of the retaining ring includes at least one of an upper bend and a lower bend and a central portion having a less pronounced curvature than the upper and lower bends such that the outer surface resembles a bucket.

5. The method of claim 1, wherein, Installing the retaining ring includes centering the retaining ring in the fuel injector sleeve through at least one of the upper and lower bends.

6. The method of claim 5, wherein, The upper bend is adjacent a generally flat upper edge of the retaining ring and the lower bend is adjacent a generally flat lower edge of the retaining ring.

7. The method of claim 5, wherein, The outer diameter of the retaining ring is greater than the inner diameter of the upper portion of the fuel injector sleeve by a distance in a range of 0.3 to 0.6 mm.

8. The method of claim 1, wherein, The outer diameter of the retaining ring is greater than the inner diameter of the upper portion of the fuel injector sleeve by a distance in a range of 0.35 to 0.5 mm.

9. The method of claim 8, wherein, 10. A system for field repair, the system comprising: ​ A retaining ring configured for field repair of a fuel injector sleeve having an upper portion and a lower portion, the retaining ring having a circular sidewall with an outer surface and defining a central opening, the outer surface having a lower portion configured to guide the retaining ring into the upper portion of the fuel injector sleeve and a central portion having a diameter greater than an inner diameter of the upper portion of the fuel injector sleeve adjacent to a location of an upper seal leak; and An insertion tool comprising: a handle including a mounting hole configured to receive a cap screw for mounting the insertion tool into a cylinder head of an engine; a threaded drive rod including a drive head and coupled to the handle; and a guide end coupled to the threaded drive rod, the guide end configured to extend into the fuel injector sleeve and through the central opening of the retaining ring, the guide end having an engagement boss that forces the retaining ring into a mounting position in the upper portion of the fuel injector sleeve in response to rotation of the drive head when the handle is mounted to the cylinder head; and wherein as the retaining ring is forced into the mounting position, the outer surface of the retaining ring compresses the upper portion of the fuel injector sleeve at the location of the upper seal leak to deform outwardly.

11. The system of claim 10, wherein, The central portion of the outer surface has a curvature that is less pronounced than a curvature of the lower portion.

12. The system of claim 11, the outer surface of the retaining ring further including an upper curved portion having a curvature that is more pronounced than the curvature of the central portion, such that the outer surface resembles a bucket.

13. The system of claim 10, wherein, The handle of the insertion tool includes an elongated portion having an opening for receiving a bolt coupled to a foot configured to engage the cylinder head.

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