1925-02-14 — Page 13

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THE SCIENCE OF

· LUBRICATION....-

WHY TECHNICAL- KNOW. LEDGE IS NECESSARY.

(Wo aro indebted to the loanl office of the Standard Old Com-|

ing informative articlo.)

HONGKONG THEGRAPH. MỚI

ING SUPPLEMENT.

BRITAIN'S POPULAR RUNABOUT.

SATU

mentioned as a foundation for all these conditions when they what is to follow Me doriand äléo 'bè able to pro- LUBRICATION OF THE ENGINE. | porly take care of the lubrication There are throw vital points to of all the movlog parts at other bo considored in the lubríostión of | spoeds.

FEBRUARY 14, 1925.

The above will be recognised as a photo of one of the "Austin Sevone", many of which are now to bo soon in the Colony,

any moving machinery: Spood, BEARING PRESSURES Pressure, and Temperaturo. In 'In the cylinders of the angino, considoring the proper oil for at the time of combustion of the astoam engine, we generally compressed mixture, the bearing: have only oho spood, one pressure is tromondous, boing pany of Now York for the follow-pressure and one temperature, something more than 340 pounds.

This is a simple matter compared to the square inch. This great THE AUTOMOBILE ENGINE. with the conditions under which pressuro is oxerted on the piston The motor, which is the heart a motor oar operates with its at the beginning of the down- and onorgy of the motor car, is varied and constantly changing|ward stroke but, of coured, is simply a machanical device to speeds, pressure and boat condi- lossened during the stroke. How- convert chemical energy into tions. Also, bear in mind that ovor, a great prossure is trans- mechanical onorgy. This chomi- one oil must lubricato all the mitted to the boaring surfacos, cal energy to commonly called by reciprocating and rotating parts and while the load at the lowar us by the short term of "GAS ", undor all those varlod conditions, end of the power stroko is not To convort this gas into power,

-SPEED BY ENGINE

|high,'tho centrifugal force of all wo ignite the mixture of vaporized There aro novorod makes of the revolving parts in the crank gas and off in the combustion ongines now in use that have's case increases the bearing pron-i chamber of the motor. To com-apead of 3500 or 3000 R.P.M., Bure vary materially. Road plete the cyclo of the stroke, the while 2000 R.P.M. is com- shocks aro also transmitted following operation takos placo: mon. By a simple process of which add to the bearing pros- 1st. The carburotion or mixing aritimatio, you will soo that sure whenever the whools scríko

of the gas and ́air.

at those speeds at 2,000 RP.M. an unovon place in the road. 2nd. Drawing the charge into (which is not unusual) and] You will 800 that in order to the cylinder on the down-figuring the stroke of piston to provide propor lubrication, these ward stroke of the piston.be 51⁄2 inches, you will got a variable pressures have got to ba 3rd. Compression of the charge (piston volocity of 1,800 foot per strongly taken into consideration..

by the upward stroke. minute and allowing the bore of ENGINE-TEMPERATURES 4th. Ignition just before the the cylinder to bo 4 inches, you The temperaturo in the com- extremes of heat, it necessarily fold stock model Indian, oasily completion of the compros-will soo that nearly 2,000 square bustion chamber of an ordinary follows that the lubricant mustasoured 1st place in the 1000 0.0. slon stroko.

foot of cyclinder are rubbed oncb motor car ranges from 250°F, be of a special nature to moot all class in 38-1/5 esconda, or 95 5th. Combustion of the com- minuto. If tho ronts shaft journal | which is the normal tomper these conditione.

miles per hour. This easily broko prossed mixture by electrio in 2 inchos in diametor, it will lature on the intake stroke, to LUBRICATING PRACTICE. all previous records: In the un- spark.

Blido ovor

bearing its

at 3000 F., at the time the charge is There are cortain fundamental limitad olass Lambort won in 6th. Expansion of the burning & rate of того than 1000 exploded. The temperature will facts that have beon proven both 37-3/5 seconds or 97 milos por

៥៥៩៧៧

foot por minuto. Of course, avorage about 1000 F., during by practical anginoorlug ox-hour Lambert then rodo an ox- 7th. Exhaust of the burned ganoa, under ordinary conditions, this this complete operation. It has perience and by scientific inhibition mile, officially timed, in All this process is probably speed is not obtained but the fact boon dotermined by enginoers vestigation that will apply to all 36-2/5 seconds or 2/5 of a second familiar to you and it is only romains that one oil must meet that the temperaturo of the oils. Iligh speeds demand light off 100 miles per hour. This is a cylinder walls is about 270°F., bodied oils. Low speeds requiro wonderful performance and is when the circulating water of the comparatively heavy bodied oils. easily the fastest milo over dono cooling systom is at a temperature High bearing prosenros requiro in Australasia. of 200. Of coures, whon the relatively heavy bodied oils. Low The machine is a stock mudol !conditions are such that the pressures requira relatively light and has now started 20 times wator in cooler than this, tae bodied oils. High temperaturos from scratch, boing placed on temperaturo of the walls is require an oil that will rotain its every occasion, obtained 24 fast- correspondingly lower. One thing body under heat. Low tempera-est times and has establishod should be borne in mind-that the ture requiro an of that will aumorous wonderful records. It aylinder temperature of an air retain ità Nuidity at low tempora- has raced under the worst posal- cooled engine is approximately tures. Heavy bodied oils have ble conditions in sand and water the same as a water cooled typo. relatively high internal friction, and still is as good as over it was.” With the cylinder wall tempore. These rulos aro universal and in ture at 270", the wall of the piston donnection with these facts, wo will be approximately 50° highor, must bear in mind that the

Harley Davidson

1924 MODELS IN STOCK FOR IMMEDIATE DELIVERY. SHEWAN TOMES & CO.

Sole Agents, Tel. C. 781.

*

and cohesion and

| while the under side of the piston qorrect motor lubricant must

hoad will reach temparatures have

qualities of ad- [from 500 to 700", This, is due, of Hosion

courao, to the fact of its hein, heat resisting proporties as will farther away from the water prevent its being forced out of jacket or the air cooling system. the hearing surfaces at the work- Part of this heat is transmitted ing tomperatures while at the to the wrist pin-connecting rod-jsame time it must he light enough crank prin- main bearings-cams in body to lubricato at the bigber and cam shaft bearings in fact to|spende...without, "khsorbing too all the moxing parts within the much power by its own internal crank caso. The temperatura of friction values. It has, hoon tho wrist pin, undor ordinary demonstrated that in all moving conditions, is in the neigbourhood machinery there'is from 20 to 40 of 300" F., while the main bearings por cont. of the initial power used Įtemperatures will rango from 100Įta ovorcomo friction. If you add to 200 F. The efficiency of the to thin, the power which would he cooling system, the questions of wasted in overcoming the fluid lead and spoed, and the character resistance of an oil, with too high of the lubricant used, also maa viscosity, you can readily son terially affect the temperature of that there would be an additional the engine. As the same oil must waste of power. Two of the most lubricato the pistons, cylinder important characteristics upon walls and all the moving parts off which correct motor lubrication the engine, at all those various depends are viscosity and host resistance. It is a demonstrated fact that all ails become thin under boat. It is thoroforo niecos- sary that the working tempora (tunes of all the lagring, surfaces, must be carefully, considered in determining the body of the lubricant to be used. It is a for- tunato fact in motor car lubrica tion that the engines are s0 designed that in the cylinders whore the temperaturos are the greatest, the, bearing presentes are low and the velocny high In this way ули CAN use compara ively bubt bodied lubricant. Al Mineral oils which are suitable for motor car ongina lubrication approach s common and suitable viscosity at a temporaturo of 300 of F. the normal temparature between the; cylinder walls and pistons underl usual condtiions. The viscosity required for correct cylinder lubrication- while it is important to a certain degree, yet it does not domand as much considera- tion as does the viscosity nocos- sary for the proper lubrication of the rotating boarings within the prank caso. Theratare. AT: oil Fihat moute the requirements in the crank сало will properly Lubricate the piston and cylinders.;

(To be concluded next week).

"Yessir, We Take A Personal Interest In Every One of Them!"

"Whether it's your car, Mr. Smith's or Mr. Brown's, it gets the same good care and expert attention at our new concrete Main Garage and Service Station (Wong Nei Chung Road-Upper end of Race Course) that every car should have.

"We know from experience that it pays to overhaul a machine regularly. Owners save money through our efficient garage service; and their cars are always bright-looking and full'er pep!”

The Dragon Motor Car Co., Ltd.

Expert and Constant European Supervision." Telephone Contral 1246 or 1247. ...

....... A. J. Allison, Service Manager.

A

(UNINTENTIATIO DUNOD A RAIN A

175

FORMANCE.

FINE SPEED RECORD.

A most onviable and unusual record for consistency in per- formance is hold by M. G. Lam-| bert and his Indian Metocycle, Mr. Lambort is an Indian rider. who performs under the auspicos of the Bell Cycle & Motor Com- pany, Indian distributors at Chrishuroh, N. Z.

The following is from a press

report -

The 1924 racing season on

1-10 JE

Comparison Confirmation

W

IS

THEN you are choosing a car, comparison alone will indicate what is best valtio and what best suits your needs. Typical of AUSTIN excellence and value and offering the cheapest travel in the world is

Austin

Seven

Has it—a

4-cylinder Engine

Ask yourself what

other car at the..

same price gives you the same performance and equipment.

Water-cooled Pump Lubrication 4-wheel Brakes

Shock Absorbers · Electric Horn

A Door for the Driver

Adjustable Seats

Grease Gun system

ASK AN AUSTIN OWNER

Standard Model Sports Model Chassis

£185.0.0 C.I.E. £170.0.0 8.0.B. £120.0.0 г.0.B.

Alex Ross & Co., (China) Ltd.

Bank of China Building Queen's Road. Tol. C. 27 or 2487.

Hongkong.

FOR HARD WORKING

TRUCKS

Trucks that have the heavy loads, that make short hauls at low speeds, that travel múddy treacherous roads, or wet and Icy streets, operate to great ad- vantage on Goodyer Heavy Duty Cushion Tyres,

These massive tyros with their big diamond shaped trend · blocks, have tremendous tractive power, fitting them- ideally to the needs of the severest service.

The powerful grip of the All-Weather Tread turns engine power lato maximum mileage.

NEAT

The Goodyear Heavy Duty Cushlon Tyre- is made with the Goodyear special side. wall indentations-a series of cup-ke depressions that assist the All-Weather Tread In providing the utmost cushioning quality.

Built with a wider a All-Weather Tread, this tyre losures road contact and trac tive power in any service.

It is built more ruggedly than ever, to give the maximum of wearing strength. and long, economical mileage, and... specially disigned for rear wheel equip ment of trucks employed in either. medium or the heaviest duty known.

TIME BUY

GOOD YEAR

HEAVY DUTY CUSHION TYRES

MADE IN CANADA DISTRIBUTORS

Bright Darren Alex. Ross & Co., (China) Ltd.

Beach with f

the Flying Mile Championships,

G. Lambert riding his foe BANK OF CHINA BUILDING.

HONGKONG.

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