US3685132A

US3685132A - Method and apparatus for removing cylinder liners of automotive vehicle diesel engines

Info

Publication number: US3685132A
Application number: US54149A
Authority: US
Inventors: James G Hodge
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-07-13
Filing date: 1970-07-13
Publication date: 1972-08-22
Anticipated expiration: 1989-08-22

Abstract

Cylinder liners are removed or extracted from diesel engines of automotive vehicles, with the diesel engine remaining mounted on the vehicle, by removing only the pistons, piston rods and the bolts holding the main bearing caps and rotating the crank shaft so that the cranks extend horizontally. The main bearing cap bolts are utilized to secure, to the undersurfaces of the main bearing caps in depending relation therefrom, a pair of substantially identical angle brackets having aligned apertures at their lower ends. A cross bar is inserted through these apertures, and a pressing tool is placed in the lower end of the cylinder liner and secured by a threaded bolt and nut to a centering device seated in the upper end of the liner. An ordinary shop jack is then positioned on the cross bar in engagement with the pressing tool, and is extended to push the cylinder liner upwardly out of the cylinder.

Description

United States Patent Hodge 1 1 Aug. 22, 1972 1 41 METHOD AND APPARATUS FOR 2,741,022 4/1956 Weaver ..29/280 x REMOVING CYLINDER LINERS OF 2,909,210 10/1959 Bennett .29/255 x AUTOMOTIVE VEHICLE DIESEL ENGINES Primary Examiner-Wayne A. Morse, Jr. Attorney-McGlew and Toren [5 7] ABSTRACT Cylinder liners are removed or extracted from diesel engines of automotive vehicles, with the diesel engine remaining mounted on the vehicle, by removing only the pistons, piston rods and the bolts holding the main bearing caps and rotating the crank shaft so that the cranks extend horizontally. The main bearing cap bolts are utilized to secure, to the undersurfaces of the main bearing caps in depending relation therefrom, a pair of substantially identical angle brackets having aligned apertures at their lower ends. A cross bar is inserted through these apertures, and a pressing tool is placed in the lower end of the cylinder liner and secured by a threaded bolt and nut to a centering device seated in the upper end of the liner. An ordinary shop jack is then positioned on the cross bar in engagement with the pressing tool, and is extended to push the cylinder liner upwardly out of the cylinder.

10 Claims, 6 Drawing Figures METHOD AND APPARATUS FOR REMOVING CYLINDER LINERS OF AUTOMOTIVE VEHICLE DIESEL ENGINES BACKGROUND OF THE INVENTION As presently used in trucks, buses and the like, diesel engines are so installed, as beneath the cab, that there is, on top of the engine, only enough clearance to allow removal of the cylinder liners or sleeves. There is no extra clearance for a sleeve puller or extractor, and this is true irrespective of whether the cylinders are vertical, at 45, or at 60. Accordingly, in order to extract or pull the cylinder liners from the engine block, it is necessary to dismount the entire engine from the vehicle and then to position a cylinder extracting arrangement on top of the engine to pull a cylinder liner upwardly out of a cylinder. 'A liner replacement operation thus involves a large amount number'of man hours of work, to dismount-the engine from the vehicle, to extract the cylinder liners, to replace new or reconditioned cylinder liners in the engine, to reassemblethe engine, and to re-mount the engine in the vehicle. In cffect, replacing a cylinder liner becomes a major and time consuming operation.

SUMMARY OF THE INVENTION This invention relates to the removal and replacement of cylinder liners of diesel engines driving automotive vehicles and, more particularly, to an improved, simplified and more efficient method and apparatus for removing and replacing the cylinder liners.

In accordance with the invention, cylinder liners are removed from automotive vehicle diesel engines while the engines remain in the vehicles. This is effected by pushing the cylinder liners upwardly out of the cylinders, operating from beneath the engine, as contrasted to the known practice of pulling the cylinder liners upwardly out of the cylinders, after the engine has been dismounted from the vehicle, and operating from above the engine.

More specifically, in practicing the method of the invention and while the diesel engine remains in mounted position on the vehicle, a cylinder head is removed, a piston and its piston rod are pulled and the crank shaft is rotated so that the respective cranks extend horizontally. The main bearing cap bolts are then used to secure, to the undersurface of the main bearing caps in depending relation therefrom, a pair of substantially identical angle brackets apertured to receive these bolts and each having an aperture at its lower end, as secured to the undersurface of the main bearing caps. A pressing tool is then positioned in engagement with the lower end of the cylinder liner, and is connected by a threaded rod or bolt and a nut to a centering device in engagement with the upper end of the cylinder liner. A cross bar is inserted through the aligned apertures of the two brackets, and an ordinary shop type hydraulic jack is positioned on the cross bar with its upper end engaging the pressing tool. The jack is then extended to push the cylinder liner upwardly out of the cylinder. If

desired, exactly the same procedure may be utilized for inserting a new or reconditioned cylinder liner into the cylinder, although this is usually effected by a different technique.

The apparatus of the invention is very simple, and in addition to the known pressing tool, includes the centering device and the threaded connection between the centering device and the pressing tool. The main elements of the apparatus include the two angle brackets for securement to the main bearing cap bolts, these brackets having longer amts formed, near their free ends, with a squareor rectangular aperture, and these apertures receive a square or rectangular cross section relatively heavy bar which supports the shop jack.

An object of the invention is to provide an improved method for removing cylinder liners of diesel engines used in automotive vehicles.

Another object of the invention is to provide such a method in which the cylinder liners are removed while the diesel engine remains mounted in position on the vehicle. A further object of the invention is to provide such a method in which the man hour requirements are only a minor fraction of the man hour requirements with present methods of removing cylinder liners from diesel engines. 1

Another object of the invention is to provide novel and simplified apparatus for removing cylinder liners from diesel engines, while the diesel engines remain mounted in automotive vehicles, and which apparatus is cooperable with ordinarily used shop tools.

A further-object of the invention is to provide such an apparatus which is simple, inexpensive, and easy to use.

Another object of the invention is to provide such an apparatus which can be used beneath the engine block of a diesel engine to remove cylinder liners.

For an understanding of the principles of the invention, reference is made to the following description of a typical embodiment thereof as illustrated in the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING In the Drawing:

FIG. 1 is a partial sectional view illustrating the apparatus of the invention as operating to remove a cylinder liner from the cylinder of a diesel engine;

FIG. 2 is a sectional view taken on the line 2-2 of FIG. 1;

FIG. 3 is a sectional view taken on the line 3-3 of FIG. 1;

FIG. 4 is a top plan view of the pressing tool;

FIG. 5 is a bottom plan view 'of the centering disk; and

FIG. 6 is a view similar to FIG. 3 illustrating an alternative arrangement of the apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawing, the engine or cylinder block of the diesel engine, for use with automotive vehicles, is somewhat schematically illustrated at 10 as formed with a cylinder 11 in which there is a cylinder liner 15. The undersurface of block 10 is formed with main bearing halves 12 receiving a crank shaft 16 held in position by main bearing caps 17 secured to block 10 by bolts 13 threaded into block 10. Shaft 16 has pairs of crank arms 14 supporting journals 18 for the piston rods.

As is well known to those skilled in the art, such an engine block is formed with axially spaced main bearings, the main bearings being disposed between adjacent cylinders. The crank shaft 16 mounted therein is formed with crank portions, including crank arms 14 and journals 18, connected, by connecting rods, to pistons which are slidable in liners such as 15. These liners are subject to wear and, after a predetermined number of hours of operation of the engine, it is necessary usually to remove a cylinder liner, or all the cyliner liners, and to replace the same with new or rebuilt cylinder liners. Prior to the present invention, such removal of cylinder liners of diesel engines used in automotive vehicles, such as trucks, buses and the like, could be effected only by removing the entire engine from the vehicle, mounting an extraction apparatus on the top of the engine and pulling the liner or sleeve, such as 15, upwardly out of each cylinder, using what is known as a pressing tool. The reason for this is that, as these engines are mounted in vehicles, there is, above the engine, only sufficient space for removal of the cylinder liner but insufficient space for mounting of an extraction apparatus on top of the engine. As a result, up to the present time many man hours of work are required to remove and replace thecylinder liners in automotive vehicle diesel engines, a good part of this time being required for removing the engine from the vehicle and replacing the engine in the vehicle.

With the method and apparatus of the present invention, the time required to remove and replace cylinder liners of an automotive vehicle diesel engine is reduced to a minor fraction of the time previously required. A major part of this reduction in man hours is due to the fact that the engine need not be removed from the vehicle, but can remain in place thereon. The principal difference in the procedure using the present invention, as distinguished from the known procedures used hitherto, is that the cylinder liner or sleeve 15 is pushed upwardly out of the cylinder rather than being pulled upwardly out of the cylinder, with all operations being performed from beneath the mounted engine.

For this purpose, the apparatus of the invention includes a pair of substantially identical relatively heavy metal angle brackets 20, arranged to be secured to engine block by main bearing cap bolts 13, and a relatively heavy substantially rectangular or square cross section bar 25 arranged to be supported by brackets 20 and to, in turn, support an ordinary shop jack, such as the usual hydraulic jack found in most bus garages and the like. In addition, a pressure tool 30 is insertable into the lower end of sleeve and is connected by a rod 27 to a centering plate 35 seated in the upper end of sleeve 15. The upper or extensible end of jack 26 is positioned in engagement with rod 27.

More particularly, the brackets comprise apertured angles 21 welded to flat straps 22, and the flat straps 22, adjacent their free ends, are formed with rectangular or square apertures or holes 23 therethrough. Cross bar 25 is cut to an appropriate length from solid rectangular or square cross section stock for insertion through apertures 23. The apertures 19 in angles 21 have diameters substantially larger than those of the shanks of bolts 13, so as to have substantial clearance therewith.

In a known manner, pressure tool is a segment of a circle centered on the diameter, as best seen in FIG. 4, and includes curved ends 31 which are circular arcs having a radius slightly less than the radius of the outer surface of liner 15. These circular arcs 31 are interconnected by parallel chords 32. The upper portion 33 of pressure tool 30 has its arcuate ends also formed as circular arcs with a radius substantially equal to the radius of the inner surface of cylinder liner 15, so that this upper portion fits within the cylinder liner while the resultant lips 34 engage beneath the lower end of liner 15. Additionally, pressure tool 30 has a central aperture 36, and may have a slot extending from this aperture, as indicated in dotted lines in H6. 4.

Centering plate 35 includes a large diameter circular upper portion 37 and a smaller diameter circular lower portion 38. Upper portion 37 has a diameter slightly less than the outer diameter of liner or sleeve 15, and lower portion 38 has a diameter substantially equal to the inner diameter of liner or sleeve 15, so as to have a snug fit therein. Centering plate 35 is further formed with a central aperture 39 having a radial slot extending therefrom.

Rod 27 interconnects pressure tool 30 and centering plate 35, and has a relatively large cross section lower portion extending through aperture 36 in pressure tool 30 and a threaded upper portion 38 extending through aperture 39 in centering plate 35 and secured thereto by a nut 39. Portion 27 has an annular shoulder 24 seating against the undersurface of tool 30, and its lower end seats on the extensible member of jack 26.

In using the apparatus of the invention to perform the invention method in removing liner 15 from cylinder 11, the appropriate cylinder head or heads are removed from block 10, the usual oil pan is removed from the bottom of block 10, the bolts 13 withdrawn from the block 10, and bearing cap 17 and crank shaft 16 is rotated so that a respective journal 18 lies in a horizontal plane. Bearing caps 17 remain in place due to their wedging fit in block 10. Thereafter, angle brackets 20 are secured by bolts 13 against the undersides of caps 17, the bolts 13 being inserted loosely through the larger diameter apertures in angles 21 and through the apertures in bearing caps 17, and threaded into block 10. This holds brackets 20 suspended from bolts 13. Cross bar 25 is then inserted through the aligned rectangular or square apertures 23.

Meanwhile, centering plate 35 is positioned on the upper end of liner 15 and pressure tool 30 is seated in the lower end of liner 15 and connected to centering plate 35 by the rod 27 inserted through aperture 36 to engage shoulder 24 with tool 30, and nut 29 threaded on rod portion 28 extending through aperture 39 in plate 35. An ordinary shop hydraulic jack 26 then has its base positioned on cross bar 25 and its extensible end is engaged with the lower end of rod 27. Jack 26 is then extended to push sleeve or liner 15 upwardly out of cylinder 11. If desired, essentially the same procedure may be used for re-inserting a reconditioned or new cylinder liner into cylinder 11, although new liners usually are inserted into the cylinder by first shrinking the liner by chilling and then sliding it into the cylinder to expand by warming to ambient temperature.

As mentioned, apertures 19 have substantial clearance with bolts 13. This permits brackets 20 to be used either in the manner shown in FIGS. 1, 2 and 3, in which each bracket depends from a single respective cap 13, or in the manner shown in FIG. 6, in which both brackets extend between adjacent caps 17.

The apparatus of the invention has the very pronounced advantage that the number of man hours required for changing the cylinder liners of a diesel engine are reduced to a minor fraction of those hitherto required by virtue of the fact that the engine remains in position on the vehicle. Furthermore, as a pusher type operation is utilized, rather than a puller type operation, the apparatus can be much more compact and much more simply handled. Additionally, the several parts of the apparatus, additional to those parts usually found in maintenance garages, are simple and inexpensive to construct and capable of long life.

While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles. 4

What is claimed is:

1. A method of removing cylinder liners of diesel engines of automotive vehicles comprising the steps of, with the engine remaining mounted in the vehicle,

removing a cylinder head; withdrawing the piston and connecting rod from the cylinder; rotating the crank shaft to position a respective crank to extend to one side;utilizing the main bearing bolts of the engine to secure, to the main bearing'caps of the engine in depending relation therefrom, a pair of substantially identical brackets; positioning a pressing tool in engagement with the lower end of a cylinder liner; supporting a jack on the brackets in engagement with the pressing tool; and extending the jack to push the cylinder liner upwardly out of the cylinder.

2. A method of removing cylinder liners of diesel engines, as claimed in claim 1, including the step of inserting a cross rod through aligned apertures in the lower ends of the brackets; and supporting the jack on the cross rod.

3. A method of removing cylinder liners of diesel engines, as claimed in claim 1, including providing centering means engaged with the upper end of the cylinder liner, and connecting the centering means to the pressing tool.

4. Apparatus for removing cylinder liners of diesel engines of automotive vehicles, with the engine remaining mounted in the vehicle, comprising, in combination, a pair of substantially identical brackets constructed and arranged for securement in depending relation to the main bearing caps of the engine by the main bearing bolts of the engine after extraction of the piston and connecting rod; support means engageable with said brackets in the mounted position of the latter; a pressing tool seated on the lower end of the cylinder liner; and a jack seated on said support means and engageable with said pressing tool; whereby said jack can be extended to push the cylinder liner upwardly out of the cylinder.

5. Apparatus for removing cylinder liners of diesel engines, as claimed in claim 4, in which said brackets are angle brackets including relatively short legs apertured to receive the main bearing bolts, and depending relatively longer legs receiving said support means.

6. Apparatus for removing cylinder liners of diesel sr saaaasmat eat ertr rstifia'sisass their free ends; said support means comprising a rod inserted through the aligned apertures.

7. Apparatus for removing cylinder liners of diesel engines, as claimed in claim 6, in which said apertures in the longer legs of said angle brackets are substantially rectangular, said rod constituting a cross bar having a substantially rectangular cross section.

8. Apparatus for removing cylinder liners of diesel engines, as claimed in claim 7, said pressure tool including centering means engaged with the liner and engageable by the extendible end of the jack.

9. Apparatus for removing cylinder liners of diesel engines, as claimed in claim 8, in which said centering means includes a pressing disk having a circular portion with a conforming fit within the lower end of a cylinder liner and a peripheral lip engageable with the lower end of a cylinder liner.

10. Apparatus for removing cylinder liners from diesel engines, as claimed in claim 9, in which said centering means further includes a centering disk having a circular portion with a conforming fit within the upper end of the cylinder liner and a peripheral lip engageable with the upper end of the cylinder liner; and a rod extending between said pressing disk and said centering disk, and having a threaded stem extending through an aperture in said centering disk for securement thereto by a nut.

Claims

1. A method of removing cylinder liners of diesel engines of automotive vehicles comprising the steps of, with the engine remaining mounted in the vehicle, removing a cylinder head; withdrawing the piston and connecting rod from the cylinder; rotating the crank shaft to position a respective crank to extend to one side; utilizing the main Bearing bolts of the engine to secure, to the main bearing caps of the engine in depending relation therefrom, a pair of substantially identical brackets; positioning a pressing tool in engagement with the lower end of a cylinder liner; supporting a jack on the brackets in engagement with the pressing tool; and extending the jack to push the cylinder liner upwardly out of the cylinder.

6. Apparatus for removing cylinder liners of diesel engines, as claimed in claim 5, in which the longer legs of said brackets are formed with apertures adjacent their free ends; said support means comprising a rod inserted through the aligned apertures.