Apparatus and method for engine prelubrication

Apparatus and method for prelubricating newly built, overhauled or rebuilt, and repaired engines including a relatively compact and lightweight pressurized vessel containing a predetermined volume of a light grade prelubricant which may, preferably, be of a specialized or proprietary formulation. The vessel is pressurized with carbon dioxide which serves as the propellant to force the lubricant through an adjustable metering valve on the vessel, an interconnecting hose and, in turn, into an engine oil port wherein the pressurized prelubricant is distributed through existing engine oil passageways, channels, and galleys.

The present invention relates to engine lubrication and, more specifically, 
to apparatus and method of prelubricating new or rebuilt engines prior to 
first use. It is well known that operation of an engine without sufficient 
oil circulation or lubrication of all moving parts, even for extremely 
short durations, results in severe wear, if not complete malfunction and 
total engine destruction. During periods of normal engine usage, a thin 
residual oil film remains on the various components following engine 
shut-down and serves to initially protect the engine against excessive 
wear until normal oil pressure and circulation can be reestablished upon 
engine restart. 
This protective residual oil coating may be insufficent or wholly absent 
from newly manufactured, remanufactured, or overhauled engines. The 
present invention, therefore, is directed to a method and apparatus for 
distributing lubricant throughout the engine prior, and without need, to 
operate the engine. In this manner, the engine will be adequately 
lubricated prior to initial operation thereby eliminating the danger of 
premature part wear and engine malfunction commonplace with engine 
`dry-starting`. More specifically, the present apparatus comprises a 
compact, lightweight, and comparatively inexpensive aerosol-type 
pressurized vessel adapted for storage and propulsion of engine 
prelubricant. 
Engine prelubrication is known to the prior art. One common prelubrication 
technique utilized to avoid engine dry-starting is to coat each engine 
moving part with lubricant or grease during engine assembly. It will be 
appreciated, however, that this technique is both time consuming and messy 
and, further, does not assure coverage of all components. In addition, the 
effectiveness of prelubrication diminishes with aging and, therefore, 
rebuilt engines stored for considerable periods may be effectively 
unprotected. The present invention facilitates prelubrication immediately 
before engine start-up without regard to the preceeding storage duration. 
One known apparatus for engine prelubrication is the Federal-Mogul Engine 
Prelubricator, model T-100. This apparatus includes a comparatively large 
and bulky prelubricator oil storage/pressure tank in which the user adds 
up to 10 quarts of prelubricant and, further, requires a motor operated 
air-compressor to pressurize the prelubricant tank and force liquid 
prelubricant therefrom. While proper engine prelubrication can be achieved 
utilizing this apparatus, the Federal-Mogul system has several significant 
drawbacks which have been overcome by the present invention including its 
relative bulk and comcomitant lack of portability, its need for an 
external source of pressurized air, its substantial cost, and the 
requirement to add engine prelubricant. 
The present apparatus, by comparison, is an inexpensive, lightweight, and 
completely portable prelubricator requiring no external air source or 
other equipment. Further, it contains a predetermined quantity of 
prelubricant sufficient to properly lubricate a single engine without the 
attendant uncertainty or waste common with known prelubricators. Finally, 
a prelubricant blend having specialized additives to inhibit oxidation, 
corrosion, and rust, and to enhance lubricity and viscosity may be 
selected by the manufacturer according to its expertise and the specific 
intended prelubrication applications. Thus, end-users need not be 
concerned with such technical matters nor be faced with a large capacity 
tank filled with an inappropriate lubricant for the specific new 
application. 
To these ends, a premeasured quantity of lubricant and additives is 
retained in a compact aerosol-type container or can having a threaded 
metering valve cap on the top thereof. The can is maintained under high 
gas pressure; the pressurized gas serving as a self-contained propellant 
vehicle. An adjustable metering valve and cap assembly screwed to the 
valve opening, a hose, and an engine crankcase coupling define the path of 
prelubricant flow. The present prelubricator is extremely easy to use 
requiring, merely, connection to the engine, typically at the oil pressure 
gauge outlet. The adjustable metering valve is opened thereby permitting 
the premeasured contents from the pressurized can to empty into the engine 
through its preexisting engine oil channels. 
Heretofore, the complexity and expense of prelubrication apparatus has 
effectively restricted its use to well equipped service and repair 
stations. The small size of the present apparatus, however, ideally suits 
it for use in a variety of locations, including field locations in which 
it might otherwise be impractical, if not impossible, to transport and 
power prior art prelubricators. Further, the use of limited, premeasured 
quantities of prelubricant in an apparatus of relatively simple, 
inexpensive design renders the present invention ideally suited for use by 
weekend mechanics as well as those desiring to guard against the dangers 
of dry-starting. Thus, it is now practical and economical to prelubricate 
where only limited engine repairs have been undertaken. 
It is therefore an object of the present invention to provide a method and 
apparatus for prelubricating engines. The apparatus shall be of relatively 
straight forward design and complexity such that it can economically be 
utilized by service stations and individuals alike. It is, therefore, a 
further object that apparatus not include large or expensive components 
such as would normally discourage its purchase by persons having only 
limited, occasional need therefor. It is an object that the apparatus 
shall be lightweight and portable permitting its use in the garage, 
driveway, or wherever and whenever the repair of engine parts becomes 
necessary. The prelubricator should preferably contain a limited, 
premeasured quantity of lubricant adapted for complete discharge during 
first use. It is a further object that the lubricant be a selected mixture 
specially suited for prelubrication. More specifically, it is an object 
that the lubricant contain additives to minimize deleterious effects of 
oxidation, corrosion, and rust as well as additives enhancing lubricity 
and viscosity. It is an object that the prelubricant be retained in a 
pressurized can wherein the internal can pressure serves to propel the 
prelubricant during use. It is a further object that an adjustable 
metering valve, hose, and fitting interconnects the pressurized 
prelubricant can with the engine oil channels, passageways and galleys.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to FIGS. 1 and 2, the prelubricator of the present invention, 
shown generally at 10, includes a highly pressurized prelubricant 
container 12 having a metering valve (not shown) positioned inside a 
threaded valve stem 14. The container is initially precharged with a 
premeasured quantity of lubricant, for example 24 ounces, generally 
sufficient to lubricate a single engine. Thus, in normal use, the entire 
contents of the can will be discharged and the can thereafter discarded. 
A lightweight lubricant must be used to facilitate passage throught the 
relatively long and narrow conveyance tube 16 and, further, proper 
distribution to all moving parts of the engine 18. Grade 120 SAS (at 
100.degree. F.) is satisfactory. The lubricant may advantageously comprise 
a special or propriety blend of additives adapted to engine 
prelubrication, for example, anti-oxidizers, metal protectors, corrosion 
inhibitors, rust preventatives and other additives to enhance lubricity. 
It will be appreciated that the present self-contained and non-refillable 
lubricator permits the manufacture to provide a superior prelubricant 
product without having to reveal to the ultimate user the precise 
chemistry thereof. 
The remaining volume of can 12 is filled with pressurized carbon dioxide 
preferably in excess of 110 psi. This gas serves as the propellant to 
force the lubricant from can 12, through interconnecting hose 16, and, in 
turn, throughout the various oil passages, galleys, and channels of the 
engine requiring prelubrication. In this manner, complete prelubrication 
of an engine is achieved without relatively large and cumbersome pressure 
tanks and, importantly, without recourse to external air compressors. The 
pressurized prelubricant is retained within the can until released through 
the metering valve in stem 14 as described below. 
FIG. 3 illustrates the metering valve actuator cap shown generally at 20. 
Cap 20 includes a vertical channel 22 and an intersecting lateral channel 
24. Internal threads 26 adapted to mate with complementary stem threads 14 
are provided along the lower portion of vertical channel 22. In this 
manner cap 22 is securely affixed to can 12 adjacent the metering valve. 
The diameter of the channel 22 bore is reduced above threads 26 to form an 
annular surface against which a washer 28 is positioned to assure 
air-tight communication between the can and cap 20. 
The central region 30 of channel 22 is also threaded to receive 
complementary threads 32 of thumb adjuster 34. Angular rotation advances 
adjuster 34 in conventional fashion along the vertical channel axis 
thereby raising or lowering the actuator pin 36 integrally affixed to 
adjuster 34. Downward movement of pin 36 progressively opens the metering 
valve through which the lubricant is expelled from the can. Conversely, 
retracting the adjuster and the actuator pin sufficiently in the upward 
direction causes the metering valve to close thereby precluding the escape 
of prelubricant. 
The upper bore region of channel 22 defines a cylinder 38 adapted to 
receive the piston-like portion 40 of adjuster 34. More specifically, a 
rubber O-ring 42, positioned in an annual slot formed in piston 40, is 
tightly received for slideable axial movement within cylinder 38. In this 
manner, the top of channel 22 is sealed against loss of lubricant or 
propellant. The lateral channel 24 intersects the central region 30 of the 
vertical channel generally at the lower part thereof so that free liquid 
and gas communication is maintained between the channels for all positions 
of the actuator 34. The intersection of channels 22 and 24 form an 
air-tight seal therebetween and, preferably, define a single integral 
member. Threads 42 are provided on the outwardly extending end of lateral 
channel 24 for connection of conveyance hose or tube 16. 
Conveyance hose 16 is preferably a flexible plastic tube of approximately 
1/8 inch diameter and of suitable length to facilitate connection to an 
engine crankcase oil pressure sensor outlet. Six feet is generally 
sufficient. A small air-tight threaded connector 44 is provided on each 
end of hose 16. This connector mates directly with the threaded end 42 of 
channel 24 and, with an appropriate washer, forms an air-tight seal 
between the hose and metering valve cap 20. An interface adapter 46 is 
required to transition from the small hose fitting 44 to the larger 1/2 
inch fitting commonly found on pressure sensor outlets. 
In operation, the several components are assembled as described and shown 
in FIG. 1 to form an overall gas/liquid-tight seal between can 12 and 
engine 18. Next, the metering valve is opened by rotating actuator 34 in 
the clockwise downward direction. The valve may be partially opened or, to 
obtain maximum pressure and oil distribution throughout the engine, the 
valve is preferably opened fully. At this instant, prelubricant under high 
pressure is propelled from can 12, through cap 20 and hose 16, and, in 
turn, into the engine oil pressure outlet. By reason of its light-weight 
and the high propellant pressure, the prelubricant easily passes through 
the various passageways, channels, and galleys defining the conventional 
engine lubrication system thereby prelubricating all engine moving parts 
without the engine damage occasioned by dry-engine operation. 
The metering valve may be closed following full prelubrication of the 
engine; although, typically, only a limited and premeasured quantity of 
prelubricant sufficient for the prelubrication of a single engine will be 
provided. In this manner the entire contents of the can are discharged 
with any engine prelubrication and the can discarded. The screw-type 
connection of cap 20 and hose 16 with can 12 facilitates reuse of the 
prelubrication apparatus merely by replacing the expended pressurized can. 
Thus, by using a pre-measured lubrication can, the user need not be 
concerned with prelubrication duration or encounter engine damage due to 
insufficient prelubrication.