journals supporting the cam shaft, the cams, the valve operating plungers, and in some cases, the timing gears. There are a number of other points, however, on the exterior of the engine that need lubrication that cannot be reached from the interior.

Q. How are the exposed parts of engine lubricated?

A. In the engine shown at Fig. 269, for example, there are a number of exposed parts that need lubrication and that must be supplied either through the medium of a hand oil can or by grease cups

Oiler.

attached to the points needing lubricant. On the top of the engine each of the valve operating rocker arms is provided with a small oil cup at its fulcrum point, or bearing on which it rocks, so these pins may be oiled daily. Some grease cups are provided on the fan supporting bracket, the timing gear case and the pump bearings. These are also intended to be screwed down one or two turns every day.

Q. What parts of cooling system need oil?

A. The only parts of the cooling system that require lubrication, other than that obtained from the interior of the engine itself, are the bearings of the fan hub and those of the pump.

Q. How are fan bearings lubricated, and how often should lubricant be applied?

A. As is clearly shown at Fig. 270, a small grease cup is screwed into the fan hub and a few turns of this member suffices to lubricate the fan properly for several hundred miles of car service.

Q. What is the method of lubricating pump bearings? A. Bearings of the circulating pump, which are of the plain bronze bushing type, need certain quantities of lubricant and this is introduced through small grease cups attached to the pump casing which are given a couple of turns each two or three hundred miles of car service.

Q. What parts of ignition system need oil?

A. Practically the only points in the ignition system requiring lubrication are the bearings of the magneto armature or the rotating parts of a primary timer.

Q. Describe lubricant to use in magneto and specify all points needing it.

A. The magneto armatures, for the most part, as well as the distributor shafts, are supported on anti-friction bearings of the ball type, and the mistake is often made of applying too much lubricant. Most magnetos have three oil holes, one over each armature bearing and one communicating to the distributor shaft bearings. Three or four drops of light sewing machine oil applied to each of these oil holes every five hundred miles of car operation is all that is necessary. A few drops should also be introduced on the rubbing parts of the contact breaker at the same time the rest of the device is oiled. If a magneto is oiled too freely, the armature may become oil-soaked which will injure the insulation and facilitate short circuit. In any event too much oil will cause serious trouble in the distributor or contact breaker by interfering with proper electrical contact of the platinum points or carbon

brushes utilized to close the primary and secondary circuits respectively.

Q. What kind of lubricant should be used in primary timer?

A. A primary timer of the rolling contact form should be lubricated with a few drops of the same light dynamo oil or sewing machine lubricant that is used in the magneto bearings. Never use lubricants containing graphite around electrical apparatus.

Fig. 271.-How Grease Cups Are Applied for Clutch Lubrication. Q. What types of clutches need oil, and how is it applied? A. Plate clutches of the multiple disc pattern are the only types designed to run in lubricant and for the most part these revolve in a bath of oil. The general rule is to drain out the clutch case every five hundred miles or so, flush out with kerosene in order to clear out all sediment and then refill with from one to two quarts of either a very light machine oil or a mixture of one-half cylinder oil and one half kerosene. The amount of oil supplied, obviously, depends upon the capacity of the clutch case.

Q. Are there any clutches that can be run without oil?

A. Practically all cone clutches whether faced with leather or Raybestos and multiple disc clutches of the dry plate type are de

signed to run without lubrication. Applying oil to clutches of this character will reduce the friction adhesion to such a point that they will not transmit power.

Q. What parts of all clutches need lubrication?

A. The actuating yoke and the bearings on which the clutch driven member revolves when it is declutched require lubrication on all types of clutches. A typical clutch yoke assembly and the points needing lubrication are outlined at Fig. 271.

Q. What is the best lubricant for clutch actuating yoke or releasing rolls?

A. The clutch actuating yoke, when of the plain bearing type, is oiled with a small compression grease cup and the rolls carried by the releasing yoke in some types are also lubricated with grease because this substance is not apt to be squeezed out by the pressure existing at this bearing point. A grease cup also communicates with the thrust and radial bearings, used to support the clutch driven members.

Q. What points of friction disc transmission need oil?

A. The bearing points on the cross shaft and on the friction driving disc shaft are usually of the anti-friction type and are packed in grease and the supply is renewed through small compression grease cups. The path for the sliding driven disc should also be kept well lubricated with oil so that this will move freely from one point to another in obtaining speed changes.

Q. Describe method of oiling planetary gearsets?

A. Planetary gearsets are either housed in a casing so they revolve in an oil bath as in the Ford automobile or are carried in oil tight cases which may be filled with a light semi-fluid mineral oil through a suitable filler plug in the side of the gear case as in Buick

cars.

Q. What is the common method of lubricating sliding gear

transmission?

A. Sliding gear transmissions are invariably designed so the gears revolve in a mass of lubricant contained in the gear case.