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Высокие технологии Reconditioned engine
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Short engine

Individual parts

Engine rebuilding alternatives

condition of the block. Other considerations are cost, access to machine shop facilities, parts availability, time required to complete the project and the extent of prior mechanical experience on the part of the do-it-yourselfer.

Some of the rebuilding alternatives include:

If the inspection procedures reveal that the engine block and most engine components are in re-usable condition, purchasing individual parts may be the most economical alternative.

The block, crankshaft and piston/connecting rod assemblies should all be inspected carefully. Even if the block shows little wear, the cylinder bores should be surface honed.

A short engine consists of an engine block with a crankshaft and piston/connecting rod assemblies already installed. All new bearings are incorporated and all clearances will be correct. The existing camshafts, valve train components, cylinder head and external parts can be bolted to the short engine with little or no machine shop work necessary.

A reconditioned engine usually consists of a short engine plus an oil pump, oil pan, cylinder head, valve cover, camshaft and valve train components, timing sprockets and timing belt covers. All components are installed with new bearings, seals and gaskets incorporated throughout. The installation of manifolds and external parts is all that's necessary.

Give careful thought to which alternative is best for you and discuss the situation with local automotive machine shops, auto parts dealers and experienced rebuilders before ordering or purchasing new parts.

6 Engine overhaul-disassembly sequence

1 It's much easier to disassemble and work on the engine if it's mounted on a portable engine stand. A stand can often be rented quite cheaply from an equipment rental yard.

Before the engine is mounted on a stand, the flywheel/driveplate and oil seal retainer should be removed from the engine.

2 If a stand isn't available, it's possible to disassemble the engine with it blocked up on the floor. Be extra careful not to tip or drop the engine when working without a stand.

3 If you're going to obtain a reconditioned engine, all external components must come off first, to be transferred to the new engine, just as they will if you're doing a complete

The do-it-yourselfer is faced with a number of options when performing an engine overhaul. The decision to renew the engine

block, piston/connecting rod assemblies and

4.22 Lift the engine out of the vehicle crankshaft depends on a number of factors, with the number one consideration being the

engine overhaul yourself. These include:

Alternator and brackets.

Emissions control components.

Thermostat and housing cover.

Water pump and remaining cooling system components.

Engine removal and overhaul procedures 2B•5

EFI components. Intake/exhaust manifolds.

Oil filter.

Engine mountings.

Clutch and flywheel/driveplate. Engine end plate.

Note:When removing the external componentsfrom the engine, pay close attention to details that may be helpful or important during installation. Note the installed position of gaskets, seals, spacers, pins, brackets, washers, bolts and other small items.

4 If you're obtaining a short engine, which consists of the engine block, crankshaft, pistons and connecting rods all assembled, then the cylinder head, oil sump and oil pump will have to be removed as well from your engine. See Engine rebuilding alternatives for additional information regarding the different possibilities to be considered.

5 If you're planning a complete overhaul, the engine must be disassembled and the internal components removed in the following order.

Intake and exhaust manifolds.

Cylinder head cover.

Timing belt/chain covers.

Timing belt/chain and sprockets. Cylinder head.

Oil sump.

Oil pump.

Piston/connecting rod assemblies.

Crankshaft oil seal retainer. Crankshaft and main bearings.

7 Cylinder head-disassembly

1 Cylinder head disassembly involves removal of the intake and exhaust valves and related components. It's assumed that the rockers/ followers and camshafts have already been removed (see Part A as needed).

2 Before the valves are removed, arrange to label and store them, along with their related components, so they can be kept separate and reinstalled in the same valve guides they are removed from (see illustration).

3 Compress the springs on the first valve with a spring compressor and remove the collets

(see illustration).Carefully release the valvespring compressor and remove the retainer, the spring and the spring seat (if used).

Caution: Be very careful not to nick or otherwise damage the follower bores when compressing the valve springs.

4 Pull the valve out of the head, then remove the oil seal from the guide. If the valve binds in the guide (won't pull through), push it back into the head and deburr the area around the keeper groove with a fine file or whetstone.

5 Repeat the procedure for the remaining valves. Remember to keep all the parts for each valve together so they can be reinstalled in the same locations.

6 Once the valves and related components have been removed and stored in an organised