Overhauls And Tuning; Recommendations For Overhauls And Tuning; Shaft Seals; O-Rings - Lombardini LDW502 Service Manual

6.1 RECOMMENDATIONS FOR OVERHAULS AND TUNING

– Information is given in a logical order in terms of timing
and sequence of operations. The methods have been
selected, tested and approved by the manufacturer's
technical experts.
– This chapter describes procedures for controlling,
overhauling and tuning assemblies and/or individual
components.
Important
To locate specific topics, the reader should refer to
the index.
– Before any intervention, the operator should lay out all
equipment and tools in such a way as to enable him to
carry out operations correctly and safely.
– The operator must comply with the specific measures
described in order to avoid errors that might cause
damage to the engine.
– Before carrying out any operation, clean the assemblies
and/or components thoroughly and eliminate any
deposits or residual material.

6.1.1 Shaft seals

– Clean the shaft thoroughly and make sure that it is not
damaged or scored or has become oval-shaped in the
areas of contact with the seals.
– Lubricate the seal lips, and pointing them in the right
direction, place them in their seat using a special pad.

6.1.2 O-Rings

– Lubricate the seal before introducing it to its seat.
– Avoid "rolling" the gasket during the attachment phase.

6.1.3 Bearings

– Use special extractors or plugs to remove bearings.
– Clean the bearings thoroughly. Check their condition and,
if they are fully intact, lubricate all over, otherwise replace
with original spares.
6.2 OVERHAULING THE CRANK GEARS AND CRANK CASE

6.2.1 Overhauling cylinders and pistons

Before deciding what kind of overhaul needs to be done, it
is important to carry out a dimensional check and verify
the correspondence of cylinders, pistons, sealing rings,
crankshaft and connecting rods.
service manual
– Wash the components with special detergent and do
not use steam or hot water.
– Do not use flammable products (petrol, diesel, etc.) to
degrease or wash components. Use special products.
– Dry all washed surfaces and components thoroughly with
a jet of air or special cloths before reassembling them.
– Apply a layer of lubricant over all surfaces to protect
them against oxidation.
– Check all components for intactness, wear and tear,
seizure, cracks and/or faults to be sure that the engine
is in good working condition.
– Some mechanical parts must be replaced en bloc,
together with their coupled parts (e.g. valve guide/valve
etc.) as specified in the spare parts catalogue.
– Do not use a hammer directly on the gaskets during
assembly, to avoid damaging them.
– Be careful not to damage the gaskets while joining them
to the shaft.
– Do not use a hammer directly on the bearings during
assembly, to avoid damaging them.
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OVERHAULS AND TUNING

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