Diesel injector sleeve remover

A tool for removing a Diesel Injector Sleeve from a Diesel engine head is built of a split, threaded expander section within which is mounted at plunger having an angled end. The plunger extends to form a handle upon which slides a weighted hammer section. The tool is inserted into the neck of an injector tube. A downward blow with the hammer drives the expander over the plunger, expanding the threads into the sidewall of the tube and creating a positive connection with the injector tube. An upward blow then pulls the plunger into the expander, maintaining a positive connection and imparting an upward force that draws the entire tube out of the head. The expander preferably has a screw thread so that the injector tube may be removed from the tool by twisting it off the expander. The tool will engage and pull an injector tube with only a partial thread engagement. A simple insertion and blow sets the expander into the injector tube; a reverse blow pulls the injector tube without requiring removal of the engine head.

BACKGROUND OF THE INVENTION 
This invention relates to the field of hand tools for pulling tightly fit 
sleeves or tubes from their mounting enclosure. 
Wendler U.S. Pat. No. 4,110,886 discloses a tool for removing a diesel 
injector. This tool, as many of the tools disclosed below, involves the 
use of a journaled impact hammer or cylindrical driving member sliding on 
a shaft to provide an impact pulling force. The active end of the tool is 
a head sized to closely fit within the central bore of a diesel injector, 
with a transverse, spring loaded pin which is adapted to mate with the 
transverse fuel passages of the injector. Means are provided for limiting 
the travel of the pin into the transverse fuel passage and for removing 
the pin from the transverse fuel passage so as to remove the injector from 
the head. 
Brooks U.S. Pat. No. 3,529,497 discloses, within the context of a dowel 
removing tool, a reciprocating plunger tool ending in an active tip which 
has an outward taper journaled to fit within an outer cylindrical member. 
The center bore of the tip of the tool is slit for expansion or 
contraction and provided with internal threads. The tool is manipulated by 
fitting the internal threads over a dowel pin and then driving the 
cylindrical member down over the taper to closely engage the threads into 
the dowel pin. The hammer is then reversed to impose a lifting force on 
the dowel pin, removing the pin. The dowel pin is solid and therefore, 
resistant to compressive forces. Only friction changes the threaded 
section within the cylindrical member during withdrawal. 
Hawkins U.S. Pat. No. 4,734,972, discloses a tool for removing a tube plug, 
a plug for sealing an unusable tube in a boiler. Such a tube plug is an 
expandable plug set with a tool in which a reverse tapered face on a draw 
bar (44) expands a toothed plug (42) into the walls of the tube 28 forming 
a tight seal which is left in place to block passage of fluids through the 
tube. The resulting tube plug is not split but is a solid plug, 
permanently expanded by deformation into a bonded relationship with the 
sidewall of a tube. The remainder of the patent discloses a particular 
concentric machine for drilling out and removing such an otherwise 
permanently affixed plug. 
U.S. Pat. No. 4,724,608 discloses an apparatus using a pulling shaft with a 
tapered lowered end, which expands a split collar gripping unit (see FIG. 
2 of the patent) so as to engage a shoulder (item 150) with the back of a 
bushing (10) allowing the bushing to be pulled by the essentially linear 
force imposed through the shoulder of the bushing port. 
A related device, a Bearing Puller, is shown in Hacker U.S. Pat. No. 
4,507,838. The puller utilizes a tapered plug to expand an otherwise 
contracted cylinder which is inserted through the axis of the bearing and 
then expanded to engage the rear shoulders. 
A third form is shown in Patton U.S. Pat. No. 2,380,068 as an oil seal 
puller. The tapered internal expanding plug is reversed in direction and 
is driven into the toothed expansion member, forcing it apart to engage 
the seal. 
Filer U.S. Pat. No. 4,280,274 discloses an apparatus for extracting tubes 
from a heat exchanger in which a multistep apparatus is disclosed. A first 
split tap thread into the tubes, which are essentially cylindrical and 
smoothwalled. A separate engaging device, much like the oil seal puller of 
Patton, is fit into an internal receiving shoulder of the screwed in drill 
tap to provide for a removing force to pull both drill tap and tube from 
the boiler. 
Both Hawkins and Filer teach that it is necessary to thread an extraction 
removal extractor unit into the wall of the tube in order to obtain a 
sufficient contact to provide a suitable pulling force. The patents 
teaching a reverse expansion device, such as Parrott or Hacker teach such 
a device not for gripping of the item to be removed but rather for 
expanding shoulders behind the item so as to impose a pulling force 
lengthwise along the tube in its strong direction. Brooks, which does 
teach the use of a tapered end sleeve for compressing a threaded member 
into an item to be removed, teaches the inward compression against a solid 
dowel. It would appear that inverting the structure of Brooks would drive 
the walls of the tube more solidly into the backing support, increasing 
the friction and resistance to removal; both Filer and Hawkins teach that 
it is necessary to thread or tap a tube to be removed, screwing a threaded 
removal into this tap. Hawkins further teaches that expanding a toothed 
element within a thin walled tube against a backing support is a method of 
plugging rather than removing the tube. 
SUMMARY OF THE INVENTION 
The invention is a device for removing a diesel engine injector tube from 
the head of a diesel engine. 
By the way of background, an injection tube is a soft copper lining tube 
inserted within the head of a diesel engine which provides the pressure 
seal when a diesel engine injector is screwed into the engine proper. Once 
an injector has been mounted, the injector tube is deformed into a 
pressure tight fit into the head of the diesel engine. The method known to 
the current art for removing an injector tube (when one requires removal 
because of a leak or a puncture) is to remove the diesel engine head and 
then to reverse punch through the bottom of the injector tube hole, 
shearing the injector tube into two sections and forcibly removing it. 
The invention comprises a split, threaded expander section within which is 
mounted a plunger having an angled end. The plunger is part of an 
extension handle upon which slides a weighted hammer section. 
The unit, with the expander journaled on the plunger, is inserted into the 
injector tube. Full insertion pushes the expander into the neck section of 
the injector tube. A downward blow with the hammer drives the expander 
over the plunger, expanding the threads into the sidewall of the tube and 
creating a positive connection with the injector tube. An upward blow then 
pulls the plunger into the expander, maintaining the positive connection 
and imparting an upward force so that the entire tube is pulled from 
within the head as a unit. 
The expander is preferably threaded in a screw thread so that the injector 
tube, once pulled, may be removed from the tool by twisting it with 
respect to the expander. 
In use the expander will engage and pull an injector tube with only a 
partial thread engagement and does not require being screwed into the 
tube. A simple insertion and blow to set the expander into the injector 
tube and then a reverse blow to pull the expander and the injector tube is 
sufficient to remove the injector tube without requiring removal of the 
engine head. 
It is thus an object of the invention to show a tool which permits the 
ready removal of a soft metal tube embedded within a hard metal backing. 
It is a further object of this invention to disclose a simple tool for 
removing diesel engine injector sleeves without requiring removal of the 
engine head.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to the drawings, I show in FIG. 4 a section of a typical diesel 
engine head containing, within the head, a soft copper injector tube 32. 
As is known in the art, such injector tubes 32 serve as a gasket sealing a 
diesel injector, which is a high pressure fuel injection mechanism into 
the head of the engine preventing blowby and leakage under the high 
pressures typically encountered in diesel engines. 
It is well known that under conditions of wear and overheat such injector 
tubes will occasionally blow out or perforate, requiring replacement. 
Equally, when an injector is removed for replacement or servicing, a new 
tube is required to be inserted so as to provide adequate sealing, 
injector tubes not being reusable. 
Under either condition therefore, it is required that the injector tube 32 
which has been deformed into tight contact with the engine head, must 
somehow be driven out and removed. 
For this purpose, I provide a tool, the invention herein. Shown in exploded 
form in FIG. 1, the tool is seen to be built upon a central shaft 4. At an 
upper end of shaft 4 is provided a handle end 6, an expanded portion, 
which can be as simple as two jam nuts, closing off the upper end of the 
shaft 4. The lower end of the shaft 4 is connected to a plunger member 8 
by being screwed together at a joint 10. Joint 10 is provided simply for 
ease of manufacture, breaking the shaft 4 into readily machinable 
elements, and also permitting the tool to be disassembled in compact form 
for carrying and storage when not in use. It can be seen that shaft 4 
could be equally made of a single uniform shaft element. 
Plunger member 8 defines a lower, insertion end 12 of the tool. Insertion 
end 12 consists of an inverted conical section 14 terminating in an impact 
tip or impact surface 16. Slidably journaled upon shaft 4 are first an 
expander member 18 and second, a hammer member 20. Hammer 20 and expander 
18 are freely movable along shaft 4, independently of each other. 
Hammer member 20 is a cylindrical, relatively heavy hammer having an 
exterior hand surface 22 adapted for grasping by one hand so that hammer 
20 may be slid or manipulated easily along shaft 4. At the end of expander 
18 closest to hammer 20 is an impact bushing 24 journaled within expander 
18 and forming an impact end of expander 18. At an end of expander 18 
opposite this impact end 20, expander 18 is divided into a plurality of 
downward extending fingers 28. Fingers 28 are slightly flexible, in the 
sense that they have, under sufficient force, the ability to bend with 
springlike action outward from the center line of expander 18. However, 
expander 18 is preferably made from a substantially strong steel tube, and 
only bends under sufficient force. 
The lower end of each of fingers 28 is provided with a serrated or toothed 
exterior surface 30. 
In use it is important to note that the shape of the typical injector tube 
32 is of a step tapered construction reducing to a neck 34. Injector tube 
32 is of soft copper so as to provide a gasket effect and has been, by the 
action of inserting and tightening an injector, deformed into tight 
sealing contact with engine head 36. 
In use, the insertion end 12 of the tool is inserted into the injector tube 
32, the injector having previously been removed. The tool is inserted 
until the impact tip 16 is in direct contact with the neck 34 of the 
injector tube. A sharp, downward blow of hammer 20 upon impact bushing 24 
forces expander 18 down against the inverted conical end 14, flexing 
fingers 28 outward and forcing tooth surface 30 into the soft copper of 
the injector tube. The injector tube having previously been forcibly 
inserted into the engine head 36, this outward expansion does not fasten 
the injector tube any more firmly into the engine. The relative hardness 
of the tooth surface 30 in comparison with the soft copper of the injector 
tube 32 insures that the tooth surface 30 engages and interlocks with the 
injector tube. However, engine head 36 is made of a relatively hard steel 
or iron construction and is thus unaffected by the insertion. 
Hammer 20 is then grasped, and a sharp, upward blow of hammer 20 against 
handle end 6 imparts a strong upward thrust on shaft 4. This upward pull 
attempts to pull plunger member 8 through expander 18 Expander 18 is fully 
engaged into the injector tube and cannot further expand over the inverted 
conical end 14 of plunger 8. Thus the upward force on plunger 8 drives 
expander 18 in an outward direction, but maintains expander 18 in a fully 
expanded state interlocked with the soft copper of the injector tube 32. 
As a result, the upward force of the second, upward blow of hammer 20 
cleanly pulls injector tube 32 free of the engine head. 
It is preferable that the toothed surface 30 of the expander 18 be in the 
form of an interrupted screw thread, as this eases the removal of the 
injector tube from the expander, once the injector tube has been pulled by 
the tool. The pulled injector tube can be unscrewed from the expander. 
This form of threaded tooth surface is not, however, necessary for the 
operation of the device and other toothed forms will work easily as well 
in performing the tube removal. 
It has further been determined that the device is relatively tolerant of 
misalignment with the injector tube. There is not a requirement that it be 
precisely aligned along the axis of the injector tube, and this is an 
advantage in a hand tool where precision alignment is difficult. In fact, 
it has been discovered that the tool actually will rock to an extent 
within the injector tube after the first downward hammer blow and yet 
still be fully effective in removing the tube during the second upward 
blow. This downward-upward impact motion is believed to be unique to this 
particular tool as is the geometry which positively locks the expander to 
the tube during the withdrawal stroke. 
It can thus be seen that the tool is not restricted to the exact embodiment 
shown but includes that range of equivalents as are claimed.