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Discussion History

Petrol Engine

Assembly

Small-displacement inline-three or inline-four spark-ignition engine. A full specification article for this item is being written. Meanwhile its bill of materials and connections are below.

Petrol Engine parts and their functions

38 top-level parts · 610 parts in total · full bill of materials below
Petrol Engine parts diagram: 1 cylinder block, 2 cylinder head, 3 piston, 4 crankshaft, 5 camshaft, 6 spark plug, 7 oil pump, 8 timing belt, 9 piston ring, 10 connecting rod, 11 connecting rod bolt, 12 bearing shell, 13 poppet valve, 14 valve spring, 15 valve retainer & collets, and 23 more. 610 parts in 38 top-level items.
Petrol Engine parts diagram. Numbers match the table below; each box is one top-level part or assembly with what it contains.
#PartQtyWhat it does
1 Cylinder Block 1× Aluminium block carrying the cylinder bores and crankcase.
2 Cylinder Head 1× Houses valves, ports, and combustion chambers.
3 Piston 4× Forged aluminium piston with rings and wrist pin.
4 Crankshaft 1× Forged-steel shaft converting piston motion to rotation.
5 Camshaft 2× Lobed shaft opening intake and exhaust valves.
6 Spark Plug 4× Ignites the air-fuel mixture in a spark-ignition engine.
7 Oil Pump 1×
8 Timing Belt 1× Toothed belt synchronising crankshaft and camshafts.
9 Piston Ring 12× three per piston
10 Connecting Rod 4× Forged rod linking a piston to the crankshaft.
11 Connecting Rod Bolt 8× High-strength bolt clamping the big-end cap to the rod.
12 Bearing Shell 18× main and big-end
13 Poppet Valve 16× Intake or exhaust valve that opens and closes a port in the cylinder head.
14 Valve Spring 16× Coil spring that closes a valve after the cam lobe passes.
15 Valve Retainer & Collets 16× Retainer cap and split collets that lock the valve spring to the valve stem.
16 Valve Stem Seal 16× Small lip seal that limits oil flow down the valve guide.
17 Valve Guide 16× Sintered bushing in the head that locates the valve stem.
18 Valve Seat Insert 16× Hardened ring pressed into the head that the valve seals against.
19 Hydraulic Lifter / Bucket Tappet 16× Cam follower that takes up valve clearance automatically with oil pressure.
20 Cylinder Head Bolt 10× Torque-to-yield bolt clamping the head to the block.
21 Cylinder Head Gasket 1× Multi-layer steel gasket sealing combustion, coolant and oil between head and block.
22 Intake Manifold 1× Moulded plenum and runners feeding air to the four intake ports.
23 Throttle Body 1× Electronically controlled butterfly valve that meters intake air.
24 Ignition Coil 4× Pencil coil on each spark plug that steps battery voltage up to the spark voltage.
25 Oil Pan 1× Sump under the block that holds the engine oil.
26 Oil Filter 1× Replaceable cartridge or spin-on filter in the lubrication circuit.
27 Flywheel 1× Heavy disc on the crankshaft that smooths rotation and carries the clutch and starter ring gear.
28 Crankshaft Pulley 1× Damped pulley on the crank nose that drives the accessory belt.
29 Accessory Drive Belt 1× Ribbed belt driving the alternator, water pump and AC compressor.
30 Belt Tensioner & Idler 3× Spring-loaded tensioner and idler pulleys for the timing and accessory belts.
31 Camshaft Cover 1× Cover over the valvetrain with the oil filler and breather.
32 Engine Sensor 12× One of the engine management sensors: crank and cam position, knock, coolant temperature, oil pressure, MAP, oxygen.
33 Engine Gasket & Seal 22× Cover, manifold, pump and pan gaskets and small seals across the engine.
34 Engine Bolt & Stud 340× Fasteners holding covers, manifolds, pumps, brackets and the pan to the engine.
35 Engine Wiring Harness 1× Sub-harness linking injectors, coils and sensors to the engine controller.
36 Connector 34× engine harness
37 Oil Seal 4× crank front and rear, cam seals
38 Ball Bearing 2× Deep-groove radial ball bearing.

3D model

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Build & assembly graph

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Bill of materials for Petrol Engine

38 top-level lines · 38 rows shown · 610 parts total · indented to 3 levels
# Item / sub-assembly Part no. Qty/assy Ext. qty Parts Type
1 Cylinder Block hatchback-car-cylinder-block 1× 1 · part
2 Cylinder Head hatchback-car-cylinder-head 1× 1 · part
3 Piston hatchback-car-piston 4× 4 · part
4 Crankshaft hatchback-car-crankshaft 1× 1 · part
5 Camshaft hatchback-car-camshaft 2× 2 · part
6 Spark Plug spark-plug 4× 4 · part
7 Oil Pump hatchback-car-oil-pump 1× 1 · part
8 Timing Belt hatchback-car-timing-belt 1× 1 · part
9 Piston Ring hatchback-car-piston-ring 12× 12 · part
10 Connecting Rod hatchback-car-connecting-rod 4× 4 · part
11 Connecting Rod Bolt hatchback-car-rod-bolt 8× 8 · part
12 Bearing Shell hatchback-car-bearing-shell 18× 18 · part
13 Poppet Valve hatchback-car-valve 16× 16 · part
14 Valve Spring hatchback-car-valve-spring 16× 16 · part
15 Valve Retainer & Collets hatchback-car-valve-retainer 16× 16 · part
16 Valve Stem Seal hatchback-car-valve-seal 16× 16 · part
17 Valve Guide hatchback-car-valve-guide 16× 16 · part
18 Valve Seat Insert hatchback-car-valve-seat 16× 16 · part
19 Hydraulic Lifter / Bucket Tappet hatchback-car-hydraulic-lifter 16× 16 · part
20 Cylinder Head Bolt hatchback-car-head-bolt 10× 10 · part
21 Cylinder Head Gasket hatchback-car-head-gasket 1× 1 · part
22 Intake Manifold hatchback-car-intake-manifold 1× 1 · part
23 Throttle Body hatchback-car-throttle-body 1× 1 · part
24 Ignition Coil hatchback-car-ignition-coil 4× 4 · part
25 Oil Pan hatchback-car-oil-pan 1× 1 · part
26 Oil Filter hatchback-car-oil-filter 1× 1 · part
27 Flywheel hatchback-car-flywheel 1× 1 · part
28 Crankshaft Pulley hatchback-car-crank-pulley 1× 1 · part
29 Accessory Drive Belt hatchback-car-accessory-belt 1× 1 · part
30 Belt Tensioner & Idler hatchback-car-belt-tensioner 3× 3 · part
31 Camshaft Cover hatchback-car-cam-cover 1× 1 · part
32 Engine Sensor hatchback-car-engine-sensor 12× 12 · part
33 Engine Gasket & Seal hatchback-car-engine-gasket 22× 22 · part
34 Engine Bolt & Stud hatchback-car-engine-bolt 340× 340 · part
35 Engine Wiring Harness hatchback-car-engine-harness 1× 1 · part
36 Connector connector 34× 34 · part
37 Oil Seal oil-seal 4× 4 · part
38 Ball Bearing ball-bearing 2× 2 · part

Where the petrol engine is used

1 product across 1 domain contain it, directly or inside a sub-assembly

Used in 1 assembly

Powertrain

Sourcing: possible vendors

Browse the supplier directory → Prices, MOQ, and lead times are algorithmic estimates, not quotes, and not claims about these companies. Company mappings are curated by keyword; est. price band $500–$50k. How estimates work
VendorHQSpecialtyMOQLead time
🇨🇳Weichai Power
weichai.com ↗ 		Weifang, CN Diesel & power engines 50 units 12–16 wks
🇮🇳Cummins India
cumminsindia.com ↗ 		Pune, IN Diesel engines 50 units 12–16 wks
🇨🇳Yuchai
yuchai.com ↗ 		Yulin, CN Diesel engines 50 units 12–16 wks
🇮🇳Kirloskar Oil Engines
koel.co.in ↗ 		Pune, IN Diesel & gas engines 50 units 12–16 wks
🇮🇳Ashok Leyland
ashokleyland.com ↗ 		Chennai, IN Engines & commercial vehicles 50 units 12–16 wks