Peugeot 405 Manual

General information
TU petrol engine in-car repair procedures / General information

How to use this Chapter 1 This Part of Chapter 2 describes those repair procedures that can reasonably be carried out on the TU series engine while it remains in the car. If the engine has been removed from the car and is being dismantled as described in Part C, any preliminary dismantling procedures can be ignored. Refer to Part B for the XU series petrol engine.

2 Note that, while it may be possible physically to overhaul items such as the piston/connecting rod assemblies while the engine is in the car, such tasks are not normally carried out as separate operations.

Usually, several additional procedures (not to mention the cleaning of components and oilways) have to be carried out. For this reason, all such tasks are classed as major overhaul procedures, and are described in Part C of this Chapter.

3 Part C describes the removal of the engine/transmission from the vehicle, and the full overhaul procedures that can then be carried out.

TU series engine description 4 The TU series engine is a well-proven engine which has been fitted to many previous Peugeot and Citroлn vehicles. The engine is of the in-line four-cylinder, overhead camshaft (OHC) type, mounted transversely at the front of the car. The clutch and transmission are attached to its left-hand end.

The 405 range is fitted with the 1360 cc version of the engine; carburettor and fuelinjected versions are available (carburettor versions not available in the UK).

5 The crankshaft runs in five main bearings.

Thrustwashers are fitted to No 2 main bearing (upper half) to control crankshaft endfloat.

6 The connecting rods rotate on horizontallysplit bearing shells at their big-ends. The pistons are attached to the connecting rods by gudgeon pins, which are an interference fit in the connecting rod small-end eyes. The aluminium-alloy pistons are fitted with three piston rings - two compression rings and an oil control ring.

7 Where the cylinder block is made of aluminium, replaceable wet liners are fitted.

Sealing O-rings are fitted at the base of each liner, to prevent the escape of coolant into the sump.

8 Where the cylinder block is made from cast iron, the cylinder bores are an integral part of the cylinder block. On this type of engine the cylinder bores are sometimes referred to as having dry liners.

9 The inlet and exhaust valves are each closed by coil springs, and operate in guides pressed into the cylinder head; the valve seat inserts are also pressed into the cylinder head, and can be renewed separately if worn.

10 The camshaft is driven by a toothed timing belt, and operates the eight valves via rocker arms. Valve clearances are adjusted by a screw-and-locknut arrangement. The camshaft rotates directly in the cylinder head.

The timing belt also drives the coolant pump.

11 Lubrication is by means of an oil pump, which is driven (via a chain and sprocket) off the right-hand end of the crankshaft. It draws oil through a strainer located in the sump, and then forces it through an externally-mounted filter into galleries in the cylinder block/crankcase. From there, the oil is distributed to the crankshaft (main bearings) and camshaft. The big-end bearings are supplied with oil via internal drillings in the crankshaft, while the camshaft bearings also receive a pressurised supply. The camshaft lobes and valves are lubricated by splash, as are all other engine components.

12 Throughout this manual, it is often necessary to identify the engines not only by their capacity, but also by their engine code which can be found on the left-hand end of the front face of the cylinder block. On models with an aluminium cylinder block the code is stamped on a plate which is riveted to the block, and on models with a cast iron cylinder block the number is stamped on a machined surface on the cylinder block, at the flywheel end. The first part of the engine number gives the engine code - eg УKDXФ (see illustration).

1.12 Engine code is stamped on a plate (arrowed) attached to the front of the
1.12 Engine code is stamped on a plate (arrowed) attached to the front of the cylinder block - viewed from above

Repair operations possible with the engine in the car
13 The following work can be carried out with the engine in the car:
a) Compression pressure - testing.

b) Cylinder head cover - removal and refitting.

c) Timing belt covers - removal and refitting.

d) Timing belt - removal, refitting and adjustment.

e) Timing belt tensioner and sprockets - removal and refitting.

f) Camshaft oil seal(s) - renewal.

g) Camshaft and rocker arms - removal, inspection and refitting.* h) Cylinder head - removal and refitting.

i) Cylinder head and pistons - decarbonising.

j) Sump - removal and refitting.

k) Oil pump - removal, overhaul and refitting.

l) Crankshaft oil seals - renewal.

m)Engine/transmission mountings - inspection and renewal.

n) Flywheel - removal, inspection and refitting.

*The cylinder head must be removed for the successful completion of this work. Refer to Section 10 for details.

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