Motor Lubrication, Mechanical Oil Pump, Motor Care and Repair

Motor Lubrication, Mechanical Oil Pump, Motor Care and Repair

What Perfect Motor Lubrication Means

The Harley-Davidson oil pump is designed to feed just the right amount of oil to the motor. With oil in the tank, a scarcity of oil in the motor is impossible. Neither can the pump feed an oversupply when properly adjusted. This makes for great economy.

More advantageous than this economy of oil is the fact that perfect lubrication eliminates excessive carbonizing of the motor and all the attendant evils. Strange as it may seem at first thought, too much oil, while not so serious as an undersupply, will eventually wear out any motor. Harley-Davidson engineers found that the only way to prevent an over­supply was to lubricate the motor by an automatic mechanical driven pump, with a large, positively operated, rotary valve working independently of temperature conditions.

 On the subject of over-oiling we want to call attention to the fact that it is not necessary to have blue smoke at the exhaust to indicate that the motor is receiving sufficient oil. There may be an oversupply of oil in the crank case and the motor not smoke. Too much oil in the crank case will cause loss of power and speed due to the overheating of the oil. Read carefully the instructions on the adjustment of the mechanical oiler and the use of the hand pump.


Serious Results of Excessive Lubrication

When a motor becomes carbonized, tiny particles of carbon gradually work into the cylinder walls, piston face and piston rings, acting as an abrasive, eventually causing wear to these parts.

Some of this carbon works past the pistons into the crank case, where the circulation of oil carries this destructive mixture to other moving

parts. If the rider neglects to flush out the crank case occasionally, this mixture of fine carbon and oil causes the cylinders, pistons, rings, bearings, crank pin, crank shafts, gears and valve action to wear excessively.

Much so-called "motor trouble" is caused by improper carburetor adjustment. To offset the poor running of the motor, due to heavy oil vapor in the combustion chamber as a result of an over-supply of oil, the rider will adjust the carburetor so that it feeds an excessively rich mixture to the motor. This mixture not only rapidly deposits carbon, but makes a slow burning or poorly combustible gas, tending to overheat the motor and causing a material loss of power. The rider in attempting to remedy this overheated condition will give the motor more oil, making matters worse than ever.

Summed up briefly, proper lubrication means sustained speed and power, and prolonged motor life. It means a uniform gas mixture and the end of most so-called "motor troubles," due to fouled spark plugs, burnt, pitted or warped valves which are often the results of an improperly adjusted carburetor, furnishing too rich a mixture to offset the effects of too much oil.

From the foregoing it is clear that too much oil is almost as serious in its effects as not enough oil. It has usually been taken for granted that as long as a motor received enough oil it made little difference whether an oversupply was used. This is positively wrong. Not only is excessive lubrication expensive from the viewpoint of the cost of the oil itself, but from the standpoint of motor service and life.

The Harley-Davidson mechanical oil pump makes it possible to adjust your oil supply to a nicety; to use just enough oil, not too much, nor too little.

Use of Hand Pump

Occasionally it is advisable to give the motor a little extra oil by means of the hand pump when speeding, negotiating a long steep hill, or when going through long stretches of heavy mud or sand, especially if the machine is carrying a sidecar and an extra passenger.