Automotive Engines R Bortignon 1 Slideshow Contents engine

Automotive Engines R. Bortignon 1

Slideshow Contents • engine classification & design - slides 3 -19 • engine problem diagnosis – slides 20 -28 Ø noise Ø poor performance Ø oil leaks • dealing with engine repairs in a high school auto shop – slide 29 2

Engine Classification - Number of Cylinders Gasoline & diesel engines may have… • 2 cylinders – Citroen • 3 cylinders – Smart For. Two, Chevy Sprint / Geo Metro • 4 cylinders • 5 cylinders – Audi, GM & Volvo • 6 cylinders • 8 cylinders 3

Engine Classification - Number of Cylinders • • • 10 cylinders – Dodge Viper, Ford Pickups 12 cylinders – Jaguar, Ferrari, Lamborghini 16 cylinders - Cadillac 4

Engine Classification - Cylinder Arrangement • cylinders can be arranged in-line 5

Engine Classification - Cylinder Arrangement • cylinders can be arranged in a “V” formation • more compact package than an in-line engine • “V” angle can be 45°, 60° or 90° 6

Engine Classification - Cylinder Arrangement • cylinders can be arranged horizontally • Subaru, VW & Porsche 911 (aka: opposed or boxer engine) Ø low center of gravity 7

Engine Classification - Cylinder Arrangement • VW’s VR 6 engine (“inline V”) Ø narrow 15° V Ø one cylinder head Ø 2 camshafts instead of 4 8

Engine Classification - Cylinder Arrangement • cylinders can be arranged in a “W” formation • more compact than a traditional V engine • Volkswagen also has a W 8 and W 16 • Bentley & Bugatti have W 16 and W 18 9

Engine Classification - Valve Arrangements • many of today's engines use more than 2 valves per cylinder • to improve volumetric efficiency, cylinder heads may have… Ø 2 intakes & 1 exhaust Ø 2 intakes & 2 exhaust Ø 3 intakes & 2 exhaust 10

Camshaft Drives • the camshaft is always mechanically connected to the crankshaft with either a timing chain • camshaft gear will always be twice as big as the crankshaft gear 11

• Camshaft Drives timing belt – must be changed at specified intervals Ø usually every 100, 000 km 12

Camshaft Drives • timing gears Ø tend to be noisy Ø very good durability Ø no scheduled replacement intervals 13

Interference Engines 14

Camshaft Locations 1) Cam-in-block: • dated technology (but still widely used) • more moving parts • valve movement is less precise • can be noisier due to more moving parts 15