Section 1

Q. What are specifications of a suitable cylinder oil?

A. The oils used for cylinder lubrication should preferably be distilled in a vacuum in order that the light distillates, such as the fuel oils, will be separated from the crude petroleum base obtained from Pennsylvania wells at low temperatures and then filtering the oil through charcoal to remove free carbon and other impurities it contains. The greater the number of times the oil is filtered the lighter it becomes in color and body. The best cylinder oils are obtained in three grades: light, which has a consistency slightly greater than machine oil; medium, which is somewhat heavier than the light and is an intermediate grade between that and the heavy bodied oil which has the consistency of warm molasses. The light and medium oils are used on power plants having closely fitting pistons and bearings, while the heavy lubricants are used in air cooled engines and in power plants that have become worn to such an extent that the cushioning properties of the heavier bodied oils are desirable. Any pure hydro-carbon oil, having a high degree of viscosity at 100 degrees F., having a vaporizing point of about 200 degrees F., a flash point between 425 and 500 degrees F., and a fire test of 600 degrees F. or over, will be suitable for use in gas engine cylinders.

Comment from Ed: This is a low tech method of making a low tech lubricant. While improvements in petroleum oils have been made since 1916, the base stock has remained pretty much the same. Synthetcs such as AMSOIL offer far better performance.

Fig. 1l5.-How Lubricating Oils May be Tested to Determine Temperature Which Oil Will Solidify.

Q. How are the various portions of an automobile lubricated?

A. The power plant of an automobile is usually lubricated by some means that will insure a continued supply of lubricant to the interior parts of the engine and that will supply the oil in quantities that will compensate for any loss through vaporizing or burning in the combustion chamber or leakage. The change speed gearset, differential gearing, universal joints and axle bearings are generally packed with a semi-fluid grease that remains in place and that does not need renewing frequently. Spring shackles, brake rod ends, and similar parts are greased by compression grease cups, which may be screwed up from time to time to inject more lubricant between the bearing surfaces or by means of small oil cups which demand periodical attention and filling from the usual form of hand oil can or syringe.

Q. Describe simplest method of oiling gas engine parts.

A. The interior of gasoline engines of the closed base form may be oiled by putting in a certain quantity of lubricant in the engine base until it rises to such a height that it will be splashed around the inside of the motor by the revolving connecting rod lower end or by counter weights or enclosed flywheel. On open base engines (never used in automobiles) the main bearings are lubricated by compression grease cups in many cases and the connecting rod by oil from a small sight feed oil cup directly attached to the crank pin bearing. A similar member of larger capacity serves to oil the piston and cylinder walls. The open base form of motor is never used in automobile practice though it has received wide application in the stationary power plants and is used to some extent in marine service.

Q. What is a sight feed lubricator?

A. The gravity sight feed lubricator is seldom used at the present time in automobiles. The first sight feed devices included a container for the lubricant having glass walls, so the amount of oil it held could be readily ascertained at any time, communicating with a lower chamber, also having glass walls, by means of a needle valve controlled orifice. The valve could be adjusted to feed any desired number of drops of oil per minute and the flow of oil could be stopped at will without changing the adjustment of the needle valve by shifting a small lever that allowed the valve to drop under slight spring pressure until it closed the passageway communicating to the small sight feed chamber beneath the main container which was piped to the point needing the lubricant. As a general rule gravity oil cups are applied directly to the parts needing oil and are generally used on cheaper marine and stationary engines.

Q. What is a compression or pressure feed lubricator?

A. A typical pressure feed lubricator is outlined at Fig. 116. This consists of a small tank holding one or two quarts of oil, which is attached to the motor at any convenient point and which is designed so the oil it contains may be put under pressure and forced through a pipe to a sight feed manifold fitting from which the individual oil leads go to the points needing oil. The pressure is usually obtained from the exhaust or by a pipe leading to the crank case interior. A small check valve fitting is carried at the end of the pressure pipe on the oil container in such a way that the air or gas under pressure will raise the check valve from its seat and flow into the oil container. As the check valve seats when the pressure of gas in the tank is sufficiently high the confined gases cannot escape and must force the oil out of the tank. The oil flows to the top of the sight feed arrangement where the amount dropping can be regulated at will and as the manifold is always carried higher than the bearing point the oil flows principally by gravity assisted to some extent by a slight pressure escaping from the oil container. As a lubricator of this nature will supply lubricant as long as there is pressure in the tank and as no oil is needed after the enginestops it is desirable to fit the container with a small petcock or relief valve which can be opened when the engine is stopped to relieve the pressure on top of the oil and thus interrupt the supply to the bearings.

Fig. 116.-Simple Compression Feed Oiler in Which Oil is Supplied From Container by Crank Case or Exhaust Pressure.

Q. Name principal methods of mechanical oiling and state their advantages.

A. There are two main methods of oiling a power plant by mechanical means, the most common one involving a single pump which keeps the oil in circulation from the oil sump or container integral with the crank case to the crank compartments, where it is picked up by the connecting rods and splashed around. The other is by individual lead sight feed oiler in which each separate bearing is supplied by its own pump plunger through an oil tube. A defect of the sight feed gravity oiling method is that the flow of oil might be stopped by any small particle of foreign matter in the oil tube or even by thickening of the oil due to lowering temperature so the bearing points would be deprived of lubricant. Much trouble resulted from this source and positive systems by which oil must be delivered to the bearing points as long as the power plant is kept in operation were evolved. With a powerful pump forcing the lubricant through the oil supply tubes it is difficult for any accumulation of lint or small piece of wax carried by the oil itself to constrict the bore of the tube and retard the flow of lubricant. The pumps have sufficient pressure so the oil, which is an incompressible liquid, will be forced to the bearing points and clear the tube or passage of obstructions tending to impede its flow. The individual lead form of oiler or mechanical oiler having a large number of individual pumps is seldom used at the present time as practically all automobile engineers favor the simpler and more positive self-contained systems.

Fig. 117.-Outlining Action of Constant Level Splash System of Haynes Car.

Q. Describe action of constant level splash system.

A. The arrangement of the crankcase interior, when used in connection with a constant level splash systerm, is clearly outlined at Fig. 117. As will be evident the crankcase is divided into two parts, the lower portion or sump being separated from the upper part in which the crankshaft revolves by a cast partition wall of corrugated form which practically divides the interior into four compartments, one for each connecting rod. A small standpipe extends from each compartment to a sufficient height so any accumulations of oil that would tend to raise the level of lubricant above the predetermined point will overflow and pass back from the crank compartments to the sump beneath them. The main bearings are oiled as shown at Fig. 118-A. The oil accumulates in the oil troughs shown at Fig. 118-B and is picked up by scoops attached to the lower connecting rod bearing cap and splashed around the interior of the crankcase. The spray or oil mist collects on all working parts and a portion of the oil will be caught by oil pockets such as shown at A and diverted to the bearing, while some of the lubricant will be splashed on the cylinder walls where it will be spread out and picked up by the rapidly reciprocating piston and reduce friction between the piston and piston rings and cylinder wall.

The diagram at Fig. 119 outlines clearly all parts of a simple constant level splash system having a sight feed on the dash. The direction of oil flow can easily be determined by the arrows. The lubricant is drawn from the sump or container at the bottom of the crank case through a screen attached to the intake pipe of a gear driven oil pump. The pump discharge goes to the sight feed on the dash and a pipe from the lowers portion of this indicator returns the lubricant to spreader members which divert the liquid into the oil troughs under the connecting rods. With this method of lubrication the oil is kept in constant circulation and as the level is always maintained at the proper height in the oil troughs, there is no possibility of the engine becoming under or over lubricated and a constant supply of oil is insured under all operating conditions.

Fig. 118.Methods of Supplying Oil to Bearings. A-Oil Pocket Above Main Bearings Which Collects Lubricant. B-Showing Scoops at Bottom of Connecting Rod to Pick Up Lubricant From Troughs in Crankcase.

Fig. 119.-Overland Constant Level Splash Lubrication System.

Q. Can oil be circulated without pumps?

A. It is not always necessary to supply a gear driven pump to circulate the oil around a power plant interior, as in some the design is such that the flywheel itself serves as an oil distributing member. A typical system of this nature is shown at Fig. 120. The power plant crankcase is inclined toward the rear end so that a pocket is formed in which the oil can collect to a certain height that will insure its being picked up by the periphery of the rapidly moving flywheel rim. The oil thrown from the flywheel is collected by a main oil pipe to an oil feed regulator controlled by the accelerator or throttle lever. From this point a portion of the oil is diverted to an oil duct which joins the four cylinders, while the remainder flows into the main oil duct cored out in the crankcase to the three main bearings. Oil passages are drilled from the main bearings to the crank throws and these are thoroughly filled with oil which after lubricating the connecting rod caps is thrown about the interior of the engine by centrifugal force and insures that all interior parts not supplied directly by the oil ducts will receive lubricant. Oil thrown by the flywheel is also diverted to the transmission gears and universal joint, from which it is returned by a pipe joining the universal joint casing with the flywheel pocket at the rear of the crankcase.

Fig. 120,-Oil Supply. System of Hupmobile Motor Depends on Flywheel to Circulate Lubricant.

  • 1916 Antique Cars Lubrication Section 2 (the next section)
  • 1916 Antique Cars Lubrication Section 3
  • 1916 Antique Cars Lubrication Tables

This information has been brought to you by AMSOIL Direct Jobber, Ed Sanders.