Volvo MD5A Manuale di istruzioni

Publ. No. 3061

Dec. 1975

WORKSHOP MANUAL

MD5A

Marine diesel engine

ENGINE UNIT

FOREWORD

This workshop manual contains repair instructions for the MD5A marine diesel engine. The instructions

concerning overhauling describe the most suitable working method to be used with the special tools listed under

the heading “Special tools”.

Both the engine designation and its serial number must be clearly stated in all correspondence concerning the

engine and when ordering spare parts. We reserve the right to carry out design modifications and, for this

reason, the contents of this manual cannot he regarded as binding.

AB VOLVO PENTA

Technical Information Department

NEW UNITS OF MEASUREMENT

Technicians have long since tried to establish an internationally standardized system of

measurements. In 1960 a decision was made to use a system called SI (Systéme International

d’Unites). To a large extent, this system is based on earlier systems but the units have been

made uniform so that no conversions are necessary.

The SI-system is now being applied within industry in Europe, This manual contains the new SI-

units. The units used previously however, are also stated but in brackets.

The new units are:

Output is slated in kW (kilowatts)

earlier unit h.p. (horsepower)

Torque is stated in NM (Newton-metres)

earlier unit kpm (kilopond-metres)

Engine speed is stated in r/s (revolutions per second)

earlier unit r.p.m. (revolutions per minute)

Displacement and volumes are stated in dm3 (cubic decimetres)

earlier unit l (litres)

Pressure is stated in Pa (Pascal)

earlier unit kp/cm2 (kiloponds per square centimetre).

Reproduction permitted if source quoted

CONTENTS

Presentation 2

Dismantling

Electrical system, thermostat housing cylinder head 3

Flywheel, fuel injector pump 4

Oil pump, transmission cover, governor 5

Lubricating oil pump, camshaft, cylinder 6

Crankshaft, cylinder liner, camshaft bearing 7

Overhauling

Lubricating oil pump, sea-water pump 7 –9

Feed pump 9 –11

Fuel filter, crankshaft 11

Centrifugal governor, piston 12 –13

Valve guides, nozzle sleeve 14 –15

Valves, valve seats, rocker mechanism, injector 15 –16

Hand start mechanism, camshaft 17

Assembling

Cylinder liner, crankshaft 18

Cylinder, camshaft, governor 19

Lubricating oil pump, transmission cover 20

Adjustment of control rod travel, assembling

flywheel cover 20 –21

Oil sump, cylinder head, feed cover 22

Fuel filter, injector, thermostat 22

Flywheel, generator, valve adjustment 24

Checking injection angle 25

Bleeding the fuel system, electrical system 26

Wiring diagram 27

Fault-tracing system 28

Special tools 29

Technical data 30 –33

Presentation

1. Connection for hand start

2. Fuse box

3. Thermostat housing

4. Decompression lever

5. Injector

6. Oil filler Cap, engine

7. Water drain tap, gearbox

8. Oil drain plug, gearbox

9. Water drain tap, engine

10. Oil filler, gearbox

11. Sea-water pump

12. Dipstick, gearbox

13. Fuel filter

14. Bleed screw

15. Hand pump, fuel

16. Dipstick, engine

17. Oil filter

Repair instructions

Dismantling

1. Drain the cooling water and the oil from the engine. Clean

externally afterwards. Loosen the water hose between the

gearbox and the sea-water pump and remove the gearbox.

3. Remove the rocker cover and the fuel pipe between the

pump and the injector and unscrew the rocker gear. Note!

Pull the rocker gear straight up since it is centred with a

guide pin 1. The other hole 2 is an oil channel.

2. Remove the generator and its drive belt, starter motor,

fuel filter and fuel pump with the drain-off pipe (be careful of

fuel spillage), coolant water pump with hose and thermostat

housing, dipstick, temperature and oil pressure sensors.

Unscrew and discard the oil filter.

4. Remove the push-rods 1, remove the cylinder head and

the cylinder head gasket. Take care of the washers 2 under

the nuts.

5. Remove the flywheel nuts. Spanner jaw width 55 mm

(2 5/32”). Use a wooden shaft or something similar as a

counter force in the flywheel spokes.

7. Remove the cover for the injection pump. Note! The

bracket for the cold start is fixed with one of the screws.

Take care of the spring under the cover.

6. Fit tool 884078 to the flywheel. Afterwards screw in the

centre screw on the tool until the flywheel loosens.

8. Prise the lower ball joint free from the pump with a

screwdriver.

9. Remove the pump screws. Position the ball in the centre

and remove the pump. 11. Remove the governor by loosening the hexagonal set

screw (1), the governor and the gear wheel can then be

withdrawn.

10. Remove the sump and then the transmission cover (13

screws). The lifting eye is fixed one of the screws. The cover

is centralised by guide pins.

12. Remove the screw and the locking washer for the

gearbox drive flange on the crankshaft and remove the

flange with a puller. (Use counter force.) Remove the key

afterwards.

13.Remove the lubricating oil pump. Discard the gasket. 15. Remove the gearwheel on the camshaft’s flywheel side

(4 screws). Then remove the camshaft and the gearwheel.

14. Remove the cover (flywheel side), 10 screws. The cover

is centred with guide pins. The screws by the guide pins are

fitted with thick washers.

16. Mark and remove the bearing cap on the crankshaft and

carefully knock out the piston through the cylinder.

19. Bearing replacement. Press out the camshaft bearings if

they are damaged or if the wear is too great (see technical

data). Clean the bearing housings and ensure that the oil

channels are clean. Press in the new bearings so that the oil

holes face the corresponding oil channels in the block. When

the bearings are pressed in position they are to be reamed

(see technical data).

17. Remove the main bearing caps. Take care of the axial

thrust bearings 1 on the transmission side. Lift the crankshaft

out and the bearing shells afterwards and then the axial

bearing halves.

18. Mark the cylinder liner’s position in the cylinder so that

the same position can be obtained during assembly.

Remove the cylinder liner. Use tool 884551. Use the long

screw and its nut from the tool 884231 (MD21-MD32). See

page 29 Special tools. Discard the 0-ring. Afterwards remove

the 0-rings in the block which provide a seal for the cylinder

liner and then remove the valve lifters. Wash all the parts

and replace those damaged.

Oilpump

20. Remove the gearwheel’s nuts and pull off the gearwheel

with a puller. The gearwheel sits on a key, take care of this

key.

21. Remove the steel wire which holds the filter. Remove

and clean the wire gauze thoroughly. Afterwards remove the

six screws which hold the cover in position. Discard the

gasket.

Overhauling the sea-water pump

23. The sea-water pump is a round flange type pump which

means that it can be fitted in a position best suited to the

coolant water hoses. The new pump is fitted with an 0-ring

which forms a seal against the engine.

22. Remove the gearwheel from the housing. Remove the

split pin for the reduction valve. Remove washer 1, spring 2

and piston 3. Clean and replace damaged parts. Assemble

the lubricating oil pump in the reverse order. Note! Fit a new

gasket 4 between the housing and the cover. Fix the wire

mesh 5 in position with the steel wire 6 and finally lay the key

in position and tighten the gearwheel 7.

24. Remove the cover (6 screws). Change the impeller with

the help of two screwdrivers or something similar. Note!

Protect the edges of the pump housing. See the figure. Prise

out the impeller with the screwdrivers so far that the screw

becomes visible.

Indice

Altri manuali Volvo Motore

Manuali Motore popolari di altre marche

Rotax

Rotax 125 senior MAX evo Manuale utente

Kohler

Kohler K361 Manuale utente

MTD

MTD OHV Series Manuale utente

Kohler

Kohler COMMAND CH18-745 Manuale utente

Mercury

Mercury D4.2L D-Tronic Manuale utente

Selve

Selve SE Plus-RC Series Manuale utente

Perkins

Perkins 1206E-E66TA Manuale utente

Skov

Skov DA 174 Manuale

Rossi

Rossi TX11 Series Manuale utente

Siemens

Siemens SIMOTICS T-1FW3 Foglio di istruzioni

AL-KO

AL-KO PRO 350 Manuale utente

MTU

MTU 12 V 4000 Lx4 Manuale utente

Nanni

Nanni N3.30 Manuale di istruzioni

Nanni

Nanni N5.160 CR2 Manuale utente

KSB

KSB SuPreme Series Istruzioni per l'installazione

Hiwin

Hiwin EM1 Series Manuale utente

Rotax

Rotax 912 i series Istruzioni operative

Siemens

Siemens SIMOTICS XP 1MB1 Manuale utente