reach the carburator. One of the following will probably account for this:—
Cause 1.—Petrol supply tap has turned itself off by vibration against tools, &c.
Cause 2.—No pressure to feed petrol.
Cause 3.—Supply pipe, filter or jet in carburator blocked with a piece of waste, asbestos, dirt, or deposit.
Cause 4.—If the tank is nearly empty, and a very steep hill is encountered, the carburator may be too high for the petrol to run into it; the remedy is to pump air pressure into the tank. '
Cause 5.—A union may be disconnected, pipe broken or plug under carburator dropped off, and you have lost all your petrol, or perhaps the tank has simply run dry. Remedy: leave your friend to sleep on the car, take list of petrol depôts, and make your way to the nearest town; if you cannot get any proper spirit, bring out some common benzoline of about ·700 gravity and take a spare tin of petrol on the car next time.
C. Carburator flooded.—If, on the other hand, there appears to be too much petrol about, and it is running out of the carburator, the float needle is stuck or bent, or the float has punctured and petrol got inside it. In the latter case, take out the float, make a hole large enough to let out the petrol, and carefully solder up air-tight again.
D. If your burners go out when you start the car, as is sometimes the case, it is due to the jerk of the car sending the petrol from the burners back towards the tank. To obviate this, the tap should be opened as little as possible.
E. If the car stops from some mechanical cause, the reason may probably be found in the former section 'Motor will not start,' or in the chapters dealing with Transmission or Ignition. Most probably it will be due to: —
i. A broken valve.
ii. Broken or misplaced spring,
iii. Valve-gear not operating properly.
iv. Something has lodged on the face of the valve, holding it open. I have known the cottar of an inlet valve and parts of
