Description

Engine / Description

1 The Uno may be powered by one of three engines depending upon the particular model.

903 cc
2 This is of four cylinder overhead valve type with a light alloy cylinder head and a cast-iron block and crankcase.

3 A three bearing crankshaft is used and the chain-driven camshaft runs in three steel backed white metal bearings.

4 The light alloy pistons are fitted with two compression and one oil control ring. The gudgeon pin is an interference fit in the small end of the connecting rod.

5 Lubrication is provided by an oil pump within the sump pan and both the pump and the distributor are driven from a gear on the camshaft. Pressurised oil passes through a cartridge type oil filter. An oil pressure relief valve is incorporated in the oil pump. The engine oil is independent of the transmission lubricant.

1116 cc and 1301 cc
6 These engines are of single overhead camshaft type, the camshaft being driven by a toothed belt.

7 The difference in engine capacity is achieved by increasing the cylinder bore on the 1301 cc engine.

8 The cylinder head is of light alloy while the cylinder block and crankcase are of cast-iron construction.

9 A five bearing crankshaft is used and the camshaft runs in a similar number of bearings, but as these are in-line bored directly in the camshaft carrier, no repair is possible.

10 The pistons are of light alloy with two compression and one oil control ring. The gudgeon pin is an interference fit in the small end of the connecting rod.

11 An auxiliary shaft, driven by the timing belt is used to drive the distributor, oil pump and fuel pump.

12 The oil pump is located within the sump pan and incorporates a pressure relief valve.

13 Pressurised oil passes through a cartridge type oil filter.

14 The crankshaft main bearings are supplied under pressure from drillings in the crankcase from the main oil gallery whilst the connecting rod big-end bearings are lubricated from the main bearings by oil forced through the crankshaft oilways. The camshaft bearings are fed from a drilling from the main oil gallery. The cams and tappets are lubricated by oil mist from outlets in the camshaft bearings.

15 The cylinder walls, pistons and gudgeon pins are lubricated by oil splashed up by the crankshaft webs. An oil pressure warning light is fitted to indicate when the pressure is too low.

All engines
16 The engine is mounted transversely with the transmission at the front of the car.

17 The engine oil is independent of the transmission lubricant.

Fig. 1.1 Longitudinal section of 903 cc engine (Sec 1)

Fig. 1.2 Cross-section of 903 cc engine (Sec 1)

Fig. 1.3 Longitudinal section of 1116 cc and 1301 cc engines (Sec 1)

Fig. 1.4 Cross-section of 1116 cc and 1301 cc engines (Sec 1)