FUEL SYSTEM - N.10Troubles in ServiceThe first symptoms of atomiser troubles usually failin one or more of the following headings:–1.Misfiring.2.Knocking in one (or more) cylinders.3.Engine overheating.4.Loss of power.5.Smoky exhaust (black).6.Increased fuel consumption.Often the particular atomiser or atomisers causingtrouble may be determined by releasing the pipe unionnut on each atomiser in turn, with the engine running ata fast "tick-over." This will prevent fuel being pumpedthrough the nozzle to the engine cylinder, therebyaltering the engine revolutions. If after slackening a pipeunion nut the engine revolutions remain constant, thisdenotes a faulty atomiser.After stopping the engine the nuts from the flange ofthe doubtful atomiser should be removed and thecomplete unit withdrawn from the cylinder head andturned round, atomiser nozzle outwards and the unionsretightened. After slackening the unions of the otheratomiser pipes (to avoid the possibility of the enginestarting), the engine should be turned until the nozzlesprays into the air, when it will be seen at once if thespray is in order. If the spray is unduly "wet" or "streaky"or obviously to one side, or the atomiser nozzle"dribbles," remove from the fuel pipe; the faulty atomisershould then be securely wrapped, preferably in grease-proof paper for attention on the maintenance bench.NOTE: Great care should he taken to prevent thehands or face from coming into contact with thespray, as the working pressure will cause the fuel oilto penetrate the skin with ease.PreparationThe most suitable bench for atomiser maintenanceis one that is zinc, linoleum or plastic covered, absolutelyfree from dust, dirt, filings, grease or acids, where noother work is done and where the use of cotton waste orfluffy rags is forbidden. It should also be provided with asmall vice (the jaws being protected with clean softcopper or aluminum shields) and a dust-proof drawer forholding the nozzle cleaning tools.An atomiser is good for service if, when operatingthe Atomiser Testing Pump at the recommended rate, itgives four effective sprays, each breaking into a very finemist and the breaking pressure is not less than theworking pressure, (refer page B.12) then the atomisermay be put back into service.Fig. N.15.Exploded view of Atomiser.1.Nozzle Holder Cap Nut.7.Spindle.2.Cap Nut Washer.8.Body.3.Locknut.9.Nozzle Needle.4.Spring Cap.10.Nozzle.5.Identification Tab Washer. 11.Nozzle Cap Nut.6.Spring.12.Copper Washer.
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business
