carburetion fuel delivery. purpose: produce mixture of fuel & air to operate an engine
TRANSCRIPT
![Page 1: Carburetion Fuel Delivery. Purpose: produce mixture of fuel & air to operate an engine](https://reader036.vdocuments.us/reader036/viewer/2022062423/5697bf761a28abf838c80e57/html5/thumbnails/1.jpg)
CarburetionFuel Delivery
![Page 2: Carburetion Fuel Delivery. Purpose: produce mixture of fuel & air to operate an engine](https://reader036.vdocuments.us/reader036/viewer/2022062423/5697bf761a28abf838c80e57/html5/thumbnails/2.jpg)
Purpose: produce mixture of fuel & air to operate an engine
![Page 3: Carburetion Fuel Delivery. Purpose: produce mixture of fuel & air to operate an engine](https://reader036.vdocuments.us/reader036/viewer/2022062423/5697bf761a28abf838c80e57/html5/thumbnails/3.jpg)
Basics:1. Air enters top of carburetor2. Mixes with liquid fuel3. Goes through passages4. Sprayed into intake manifold5. Burned in combustion chamber
![Page 4: Carburetion Fuel Delivery. Purpose: produce mixture of fuel & air to operate an engine](https://reader036.vdocuments.us/reader036/viewer/2022062423/5697bf761a28abf838c80e57/html5/thumbnails/4.jpg)
Operates based on different pressures
Cylinder has no atmospheric pressureAir/fuel mixture is pushed into cylinder by
atmospheric pressure in the carb
![Page 5: Carburetion Fuel Delivery. Purpose: produce mixture of fuel & air to operate an engine](https://reader036.vdocuments.us/reader036/viewer/2022062423/5697bf761a28abf838c80e57/html5/thumbnails/5.jpg)
Venturi principle- Restriction in a passage creates a vacume.
( Causes air to move more rapidly)
![Page 6: Carburetion Fuel Delivery. Purpose: produce mixture of fuel & air to operate an engine](https://reader036.vdocuments.us/reader036/viewer/2022062423/5697bf761a28abf838c80e57/html5/thumbnails/6.jpg)
Carbs come in many styles & typesNatural draft- air flows horizontally into
manifoldUpdraft- a/f mixtures forced upward
toward engineDowndraft- gravity assists air into
manifold
![Page 7: Carburetion Fuel Delivery. Purpose: produce mixture of fuel & air to operate an engine](https://reader036.vdocuments.us/reader036/viewer/2022062423/5697bf761a28abf838c80e57/html5/thumbnails/7.jpg)
Float type carburetorsFloat= maintains constant level of fuel in
float bowl
When fuel is used float unseats needle valve and allows fuel to enter the bowl
![Page 8: Carburetion Fuel Delivery. Purpose: produce mixture of fuel & air to operate an engine](https://reader036.vdocuments.us/reader036/viewer/2022062423/5697bf761a28abf838c80e57/html5/thumbnails/8.jpg)
Choke- Round disk mounted on shaft at the intake end of the carb.
Closed= provides more fuel to the engine to allow starting
![Page 9: Carburetion Fuel Delivery. Purpose: produce mixture of fuel & air to operate an engine](https://reader036.vdocuments.us/reader036/viewer/2022062423/5697bf761a28abf838c80e57/html5/thumbnails/9.jpg)
Adjusting needle- adjusts the amount of fuel entering the nozzle to be discharged.
Sometimes these are pre-set & non adjustable
![Page 10: Carburetion Fuel Delivery. Purpose: produce mixture of fuel & air to operate an engine](https://reader036.vdocuments.us/reader036/viewer/2022062423/5697bf761a28abf838c80e57/html5/thumbnails/10.jpg)
Primer- hand operated plungerForces additional fuel through main
nozzle. Mainly used to start cold engines
![Page 11: Carburetion Fuel Delivery. Purpose: produce mixture of fuel & air to operate an engine](https://reader036.vdocuments.us/reader036/viewer/2022062423/5697bf761a28abf838c80e57/html5/thumbnails/11.jpg)
Governor◦Maintain a selected speed◦Prevent over-speeding that could cause engine
damage◦Limit high & slow speeds
![Page 12: Carburetion Fuel Delivery. Purpose: produce mixture of fuel & air to operate an engine](https://reader036.vdocuments.us/reader036/viewer/2022062423/5697bf761a28abf838c80e57/html5/thumbnails/12.jpg)
Air CleanersEngines must have clean air!Dust/moisture ruin engines
![Page 13: Carburetion Fuel Delivery. Purpose: produce mixture of fuel & air to operate an engine](https://reader036.vdocuments.us/reader036/viewer/2022062423/5697bf761a28abf838c80e57/html5/thumbnails/13.jpg)
Servicing an Air CleanerChange ever 25 hours on lawnmowersFollow manufacturers instructions