General information. Torque wrench settings

Torque wrench settings

Refer to Part A for torque specifications.

Included in this portion of Chapter 2 are the general overhaul procedures for the cylinder head and internal engine components.

The information ranges from advice concerning preparation for an overhaul and the purchase of new parts to detailed, step-by-step procedures covering removal and installation of internal engine components and the inspection of parts.

The following Sections have been written based on the assumption that the engine has been removed from the vehicle. For information concerning in-vehicle engine repair, as well as removal and installation of the external components necessary for the overhaul, see Chapter 2A and Section 8 of this Chapter.

The Specifications included in this Part are only those necessary for the inspection and overhaul procedures which follow. Refer to Part A for additional Specifications.

2 Engine overhaul-			4 Check the oil pressure with a gauge fitted in
		place of the oil pressure switch, and compare
general information	it	with	that	specified. If it is extremely low,
			the main and big-end bearings, and/or the oil
			pump, are probably worn out.
1 It is not always easy to determine when, or	5 Loss of	power, rough running, knocking or
if, an engine should be completely overhauled,	metallic engine noises, excessive valve gear
as a number of factors must be considered.	noise, and high fuel consumption may also
2 High mileage is not necessarily an indication	point to the need for an overhaul, especially
that an overhaul is needed, while low mileage	if they are all present at the same time. If
does not preclude the need for an	overhaul.	a complete service does not remedy the
Frequency of servicing is probably the most	situation, major mechanical work is the only
important consideration. An engine which has	solution.
had regular and frequent oil and filter changes,	6 A full engine overhaul involves restoring
as well as other required maintenance, should	all internal parts to the specification of a
give many thousands of kilometers of reliable	new engine. During a complete overhaul, the
service. Conversely, a neglected engine may	pistons and the piston rings are renewed, and
require an overhaul very early in its life.	the cylinder bores are reconditioned. New
3 Excessive oil consumption is an indication	main and big-end bearings are generally fitted;
that piston rings, valve seals and/or valve	if necessary, the crankshaft may be reground,
guides are in need of attention. Make sure that	to compensate for wear in the journals. The
oil leaks are not responsible before deciding	valves are also serviced as well, since they
that the rings and/or guides are worn. Perform	are usually in less-than-perfect condition at
a compression test, as described in Part A of	this point. Always pay careful attention to the
this Chapter, to determine the likely cause of	condition of the oil pump when overhauling the
the problem.			engine, and renew it if there is any doubt as to

Engine removal and overhaul procedures 2B•3

its serviceability. The end result should be an as-new engine that will give many trouble-free kilometers.

7 Critical cooling system components such as the hoses, thermostat and water pump should be renewed when an engine is overhauled. The radiator should be checked carefully, to ensure that it is not clogged or leaking. Also, it is a good idea to renew the oil pump whenever the engine is overhauled.

8 Before beginning the engine overhaul, read through the entire procedure, to familiarise yourself with the scope and requirements of the job. Overhauling an engine is not difficult if you follow carefully all of the instructions, have the necessary tools and equipment, and pay close attention to all specifications. It can, however, be time-consuming. Plan on the car being off the road for a minimum of two weeks, especially if parts must be taken to an engineering works for repair or reconditioning. Check on the availability of parts and make sure that any necessary special tools and equipment are obtained in advance. Most work can be done with typical hand tools, although a number of precision measuring tools are required for inspecting parts to determine if they must be renewed. Often the engineering works will handle the inspection of parts and offer advice concerning reconditioning and renewal.

9 Always wait until the engine has been completely dismantled, and until all components (especially the cylinder block/ crankcase and the crankshaft) have been inspected, before deciding what service and repair operations must be performed by an engineering works. The condition of these components will be the major factor

to	consider	when determining	whether
to	overhaul	the original engine,	or to buy

a reconditioned unit. Do not, therefore, purchase parts or have overhaul work done on other components until they have been thoroughly inspected. As a general rule, time is the primary cost of an overhaul, so it does not pay to fit worn or sub-standard parts.

10 As a final note, to ensure maximum life and minimum trouble from a reconditioned engine, everything must be assembled with care, in a spotlessly-clean environment.

3 Engine removal -methods and precautions

1 If you have decided that the engine must be removed for overhaul or major repair work, several preliminary steps should be taken.

2 Locating a suitable place to work is extremely important. Adequate work space, along with storage space for the car, will be needed. If a workshop or garage is not available, at the very least, a flat, level, clean work surface is required.

3 Cleaning the engine compartment and engine/transmission before beginning the

removal procedure will help keep tools clean and organised.

4 An engine hoist or A-frame will also be necessary. Make sure the equipment is rated in excess of the weight of the engine. Safety is of primary importance, considering the potential hazards involved in lifting the engine/ transmission out of the car.

5 If this is the first time you have removed an engine, an assistant should ideally be available. Advice and aid from someone more experienced would also be helpful. There are many instances when one person cannot simultaneously perform all of the operations required when lifting the engine out of the vehicle.

6 Plan the operation ahead of time. Before starting work, arrange for the hire of or obtain all of the tools and equipment you will need.

Some of the equipment necessary to perform engine/transmission removal and installation safely and with relative ease (in addition to an engine hoist) is as follows: a heavy duty trolley jack, complete sets of spanners and sockets

(see Tools and working facilities), wooden blocks, and plenty of rags and cleaning solvent for mopping-up spilled oil, coolant and fuel. If the hoist must be hired, make sure that you arrange for it in advance, and perform all of the operations possible without it beforehand. This will save you money and time.

7 Plan for the car to be out of use for quite a while. An engineering works will be required to perform some of the work which the do-it-yourselfer cannot accomplish without special equipment. These places often have a busy schedule, so it would be a good idea to consult them before removing the engine, in order to accurately estimate the amount of time required to rebuild or repair components that may need work.

8 Always be extremely careful when removing and refitting the engine/transmission. Serious injury can result from careless actions. Plan ahead and take your time, and a job of this nature, although major, can be accomplished successfully.

Note: Such is the complexity of the power unit arrangement on these vehicles, and the variations that may be encountered according to model and optional equipment fitted, that the following should be regarded as a guide to

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