Alto Contractor Diesel Operating instructions

Repair Manual
CONTRACTOR DIESEL
125 03 47 (03.2003)
www.alto-online.com
2003-11-14

Copyright © 2003
ALTO Danmark A/S
ALTO Danmark A/S
Industrikvarteret
DK-9560 Hadsund
Tel.: [phone]
www.alto-online.com

A Technical data
B Structure
C Function
D Trouble-shooting
E Service / Repair
F Test / Adjustment
G El. diagrams
H Spare parts proposal
I (Info & spare parts)
INDEX
CONTRACTOR
Diesel
Petrol

4D_CON. 03GB.
CONTRACTOR Diesel Motor data A
Diesel motor RUGGERINI MD 151, S
Engine type 4 stroke two cylinder
Max. output at 3600 rpm 13 HP / continuous 12.3 HP
Max. torque st 2400 rpm 3.26 Kgm
Fuel consumption Approx. 3 l/h
Fuel tank capacity 4.1 l
Adjusted speed at max. pressure 3500±10 rpm
Cooling system Forced air 700 m3/h
Air requirement for combustion 62 m3/h
PTO shaft rotation clockwise
Max. vacuum intake 0.024 bar
Max. exhaust backpressure 0.039 bar
Engine oil capacity / type 1.8 l / SAE 15 - 50
Dry weight 50 kg

D_CON. 03GB. 5
125 03 47 - (03.2003)
CONTRACTOR Diesel Pump data A
Heavy Duty
Opening pressure 210 bar 225
Pump pressure 180 bar / 2550 psi 205
Nozzle pressure 170 bar / 2410 psi 195
By-pass pressure 8 bar 10
Water quantity at min./max. pressure 20/19 l/min. 17.5/16 l/min.
Water quantity at steam 9 l/min. 8 l/min.
Pump pressure at steam 40 bar 30 bar
High pressure nozzle 1506 = 1.35 mm 1505
Max. temperature of inlet water 35°C 35°C
Inlet pressure, max. 10 bar 10 bar
Chemical injector (external only) 03 injector / foam injector
Density (control box) IP45
Engine r.p.m. (pump pressure) 1750 ± 25 r.p.m.
Noise level according to ISO 3746 85 DB(A) from 7 m distance
Type of piston Stainless steel Ceramic
Wobble disc no. 7 3
Type of oil BP Bartran HV 100

6D_CON. 03GB.
CONTRACTOR Diesel Boiler data A
Heavy Duty
Boiler effect 115 kW 100
Water outlet temp. at max. water quantity (12°C) 95°C (205°F) =
Oil consumption at max. water quantity and temp. 12 l/h 10 l/h
CO210-12% =
CO 50-100 ppm =
Temp. flue gas at 20°C ambient temp. 160-200°C =
Smoke scale number Max. 1 =
Flue gas loss Max. 10% =
Oil nozzle type 9 kg/h - 60°S =
Oil pressure 12 bar 11 bar
Boiler tube / measurements Welded st. 35.8 / 20 x 3mm x 48m
Heating surface 3 m2
Quantity of inlet air Approx. 180 m3/h
Outlet flue gas 260 m3/h at 200°C
Tank capacity max./min. Jerry can 20 l / 3 l

D_CON. 03GB. 7
125 03 47 - (03.2003)
CONTRACTOR Diesel Electrical parts A
A1 KEW-steering 24V AC 642009A
A2 KEW-converter 12V DC / 24V AC 6420013
B1 Flow control After pump magnet oper. Reed-switch
B2 Flow control Before boiler magn. oper. Reed-switch
B4/B5 Temperature sensor PT500
B6 Flame sensor Light-sensitive transistor
B67 Motor oil switch Open at a normal oil pressure
F1 Fuse on print A2 1 AT
F2 Fuse on print A2 *) 6.3 AT
F3 Fuse for PC-board A1 (see page 5) 1.25 AT
F4 Fuse for start protection (see page 5) 1.25 AT
G1 Accumulator battery 12V min. 50 AH (300 Amp.)
G2 Generator internal/external 12V - 15V - 280 Watt / 300 Watt
G3 Regulator/Rectifier
H1 Motor oil alarm Lamp on front
H2 Starting relay Lamp on front
M1 Starting motor 1.1 kW
R1 Resistance (only where B5 is not used) 560 ohm
S1 Start switch Key on front
T1 Ignition transformer Prim: 2x12VAC/17 Amp. Sec. 11KV
Y1 Magnet valve for oil pump 24 VAC
F3 *) secure against fault polarization of battery

8D_CON. 03GB.
Electrics box
Manometer for HP-pump
Back of electrics box
Fuses
F3
F4
Pump oil Diesel tank for motor
Ignition key
Starter battery
Ignition transformer
Exhaust outlet from boiler
Motor suspension
The base plate for the motor/pump unit is mounted on 4 inclined vibration absorbers.
The boiler is mounted on a plate construction, which serves as air duct from blower to boiler.
Electrics box is suspended in the pipe frame and contains the controlling and safety system of the
machine
Exhaust from motor
Control lamps
H1 H2
Setup Structure B
The Contractor is constructed on a combined pipe and plate frame, surface coated with a strong poly-
ester. Each single item of the machine is placed in a way that an optimum weight distribution is obtained
taking service and operation into consideration.
Temperature indicator Front panel
Temperature regulation
Chemicals container rack

D_CON. 03GB. 9
125 03 47 - (03.2003)
Diesel oil for pump
Setup Structure B
Water quantity regulation
Pump front
Water inlet
Water outlet
Pressure outlet
Sludge glass
Manometer
Flow switch B1
Electromagnet Y2 Y3 (safety stop)
Oil pressure
switch B7
Starter relay Starting motor
Rectifier G3
Motor connection (- pinch)
Gearbox
Motor air filter
Fuel oil pump Flow switch B2
Air adjustment screw
Blower
Flexible coupling
Solenoid
valve Y1
Flow
switch B2

10 D_CON. 03GB.
A flame tube consisting of two rings has the purpose of securing that the hot exhaust gases are forced
round the labyrinth of tubes.
The boiler is mounted on the air duct with a gasket between and fastened with 3 bolts. In the air duct
an adjustable throttle is mounted.
Boiler Structure B
The boiler is the heat generating part of a hot water machine. It consists of a labyrinth-constructed
tube coil, which encloses the combustion chamber.
The tube coil is enclosed by a double container with boilerjacket, bottom, and top in a sandwich con-
struction, between which the combustion air is pressed into the combustion. An insulating material
placed in the bottom of the boiler makes sure that the inner bottom, among other things, is protected
from superheating.
Gasket
Exhaust gas Electrodes Flame sensor
Oil nozzle
Air distributor
Burner tube
Flame tube bottom part
Insulating mat
Water outletWater inlet Air inletGasket
Outer jacket
Flame tube top part
Inner jacket
Air duct

D_CON. 03GB. 11
125 03 47 - (03.2003)
C3
WOBBLE DISC
The pump is a 4 cyl. axial pump model 03 with standard sealing system and steel pistons, or model C3
with textile seals and and ceramic pistons.
The pump is driven by the motor through a gear, which reduces the number of revolutions of the spindle
from 3500 rpm to 1750 rpm.
Gear wheel
Gasket
Roller bearing
Oil glass
Cylinder cover
Pistons
Clamping ring
Valve cylinder head
Pressure valve
By-pass valve
Non return
valve
Pressure outlet
Safety valve
Suction valve
Pressure seal
Suction seals
Oil seals
Sludge container
Oil drain
Oil seal
Oil drain
Motor shaft D-cover
Wobble disc
No. 3No. 7
HDStandard
Drain channel
Textile seal
Back-up seal
Oil seal
HD
Standard
Valve piston
Pump Structure B

12 D_CON. 03GB.
Max
Operating diagram Function C
The fuel is drawn from the jerry can through the fuel filter to the pump, while in hot mode it is passed
through the magnetic solenoid valve to the nozzle in the air distributor.
The ignition transformer is active for approx 6 sec., and during this period it will form sparks between
the electrodes.
If the flame is not developed within this time, a flame sensor placed on top of the boiler will secure that
the machine is automatically stopped.
When the machine is running normally, and the boiler is burning normally, the flame is pressed against
the insulated bottom. The temperature is here approx. 1100°C. The hot exhaust gas is pressed further
round the labyrinth-shaped combustion chamber, where the heat is absorbed by the water flow in the
tubes.
Air distributor
Fuel nozzle
When the Contractor is running, the fan draws in air and leads it through a channel with an air volume
adjustment and into the bottom of the boiler, around and between the two jackets up to the air distributor.
In this way the air is preheated, before it is mixed with the oil spray from the nozzle.
Fuel filter
Fuel tank
Magnet
valve
Air
in-take
Fan
Fuel pump
Oil pressure damper
Air adjustment
Insulation

D_CON. 03GB. 13
125 03 47 - (03.2003)
Y1
B3
B7
B4
B2
B1
B5
BOILER
Operating diagram Function C
The flow system is simple with direct water inlet to the pump (water tank can be mounted), on which an
adjusting screw permits infinitely variable regulation of the water quantity. From the pump the water pas-
ses two flow controls, before it flows through the approx. 30 m pipe line of the boiler. On the outlet pipe
the temperature sensors are placed (2 sensors are mounted, where priming safety is necessary).
Water inlet
Water quantity
regulation
Pressure water outlet
B1, B2 flow switch The flow switch detects whether there is water and thereby a flow in the system.
If one of the flow switches disconnects because of a failing flow, the oil supply
will be shut off after 4 seconds.
B4, B7 temperature
sensors
The temperature sensors are PT500 elements sensing the water temperature at
the outlet of the boiler. The function of the sensors is, in a cooperation with the
electronics, to check the outlet temperature of the water compared to the preset
value, see also page 12.
B5 flame sensor The flame sensor is a light-sensitive transistor mounted at top of the boiler. Its
function is to detect whether the flame is on. If the burner does not ignite, the
engine will stop within approximately 5-10 sec. In order to start the engine again,
turn the ignition key in position „off“.
Y1 magnet valve On the fuel oil pump the magnet valve Y1 is controlling the injection of oil into the
boiler and by that the temperature. Y1 opens to the fuel oil, when B1 and B2 are
activated at the same time, and the temperature setting is higher than the actual
water temperature on the outlet from the boiler.
Water outlet from
the machine

14 D_CON. 03GB.
Operating diagram Function C
The controlling and safety system of the Contractor consists of the PC-board A1, the main task of which
it is to secure operation and safety of the boiler system. The PC-board A2 is a converter, the main tasks
of which it is to convert 12 V DC to 24 V AC and to supply the ignition transformer with 2x12V AC.
A1
A2
B7
F1
F2
F3
F4
G1
G2
G3
H1
H2
M1
R1
S6
S1/2
S3/4/5
JP1
X2/3
X4
T1
Y1
Y2/Y3
KEW control
12V DC/24V AC converter
Motor oil switch
Fuse 1AT
Fuse 6.3A
Fuse 1.25AT
Fuse 10AT
Accumulator 12V
Generator
Regulator / rectifier
Oil Pressure indicator
Charging indicator
Starting motor
Ohmic resistance
Start switch
12V DC from Accumulator
2x12V AC to ignition trafo
9 Pole plug on A2
8/12 Pole plug on A1
Charging plug
Ignition trafo
Solenoid valve fuel
Hold & Draw coil
When the motor is running, the generator G2 supplies 12 Volt DC to the converter A2, and the converter
supplies 24 Volt DC to the control PC-board A1. The motor is automatically stopped at flame failure and
at lack of lubricating oil in the motor.
F1 Fuse on A2 secures the PC-board against too big charging rate
F2 Fuse on A2 secures against wrong polarization of battery
F3 Fuse on El-box secures A1 against overload
F4 Fuse on El-box secures A2 against overload at starting of motor
B7 Motor oil alert The motor oil alert is a pressure gauge mounted on the engine.Usually the
pressure gauge is closed but at a normal oil pressure it will be open. If the
engine runs dry of oil, the switch will close and thereby stop the engine.
12V
-
Boiler
Start Motor M1
Y3
S6
T1
A2
A1
S6
Y1
Y3
Y2
A2
G2
B7
G3
87654321
safe pump oil motor 24V
F3
F4

D_CON. 03GB. 15
125 03 47 - (03.2003)
A1
x2
08
09
safe pump 24Vmotor oil
189
x3
12
x3
B1B2B4B7B5
SLOW
150
8 7 6 5 4 3 2 1
x2
EL.-control Function C
The A1 PC-board is supplied with 24V AC from the converter PC-board A2, and it is controlling the oil
injection (Y1) into the boiler with a 24V signal of X2, 4 and 5. This on/off signal is e.g. controlled by the
flow controllers B1 and B2, which are each equipped with a Reed switch making contact when there is
a flow through the machine.
If both flow controllers are not making contact at the same time (max. time difference approx. 4 sec.), the
signal for oil injection (Y1) will disconnect and close, until the machine is stopped and restarted.
The temperature regulation is getting information from the temperature sensor B4 (PT500) placed in the
outlet pipe from the boiler and from the adjustable potentiometer placed on the PC-board. The result is
together with B1 and B2 controlling the signal for oil injection (Y1).
A safety thermostat (priming safety) B7 is securing that the machine stops, if the temperature of the
boiler outlet pipe exceeds approx. 173°C. On some machines this additional safety is replaced by a
built-in resistance.
The flame supervision circuit is connected to a light sensor B5 (X3.11 and X3.12) in the top of the boiler
and stops the machine under the following conditions:
a) If a flame has not occured within 5-10 sec. after the thermostat output has closed.
b) If the flame disappears for more than 5-10 sec. while the thermostat output is closed.
c) If the flame is present 15-30 sec after the thermostat output has opened.
d) If a flame breaks out and stays for more than 15-30 sec. while the thermostat output is open.
e) If the light sensor is short-circuited or disconnected.
Plug for test box no. 6420100, see page 32.
Temperature range
selector

16 D_CON. 03GB.
123456789
F2
S2 S1
S4 S3 S5
F1
JP1
KEW 6420013
1. The converter is supplied with 12-15 VDC.
2. The converter supplies the control unit 6420009 with 24 VAC/55 Hz, when the engine is running (rpm
> 2500).
3. The converter supplies the ignition transformer with 2x12VAC, when the engine is running (rpm >
2500) and there is a signal on „Pump“. The ignition transformer is active for approximately 6 sec.
If new signal displays within the 6 sec., the time will start all over again.
4. The converter is protected against polarization errors, i.e. a fuse (F2) will blow if the cables of the
battery are interchanged.
5. The engine is stopped by a signal at the Safe inlet. Disconnect the converter (Key off) before
restarting the engine.
6. The engine is stopped by a signal at the inlet of the pressure gauge.
7. The converter features an excess temperature cut-out breaking the voltage for the ignition
transformer at a temperature > 90°C.
Supply voltage: 12-15 VDC
Outlets:
Supply for KEW 6420009: 24VAC ± 15% 0.5A
55Hz ± 15%
Voltage for the ignition transformer: 2x12VAC ± 15% 17A
100Hz ± 15%
EL.-control Function C
Starting rev., 24VAC: 2500 rpm ±10%
Declutching rev., 24VAC: 2300 rpm ±10%
Temperature range: 0-65°C
Securing of temperature
- ignition transformer: Interrupts at 90°C
±5°C
Connections:
S1: +battery
S2: -battery
S3: ignition transformer
S4: double wire ignition transformer
S5: ignition transformer
input from 1 Pressure switch B7
input from 2 Safe, X2-8 on 6420009
input from 3 Pump, X2-6 on 6420009
output to 4 24VAC (0), X2-2 on
6420009
output to 5 24VAC (f), X2-1 on
input from 6 Key, +12V from key
output to 7 Engine off, Y2 on engine
input from 8 G2 on engine
input from 9 G2 on engine

D_CON. 03GB. 17
125 03 47 - (03.2003)
30/1 30
15/5415 50
0
1
start
Switch
position
oil
+-
H1
H2
S6
B7
Y3/Y2
G1
G3
M1
G2
15/54
30 30/1
15 50
+
When the ignition key in starter switch S6 is turned into position 1, contact is made.
30/1 to 15 - by that H1 lights and contact is made.
30/1 to 15/54 - by that H2 lights.
When the ignition key is turned into position “start”, contact is made.
30/1 to 50 - by that starter relay and starting motor are activated. At the same time the draw coil Y3 is
activated, which is thereby opening for the fuel to the motor. The motor accelerates, and oil pressure
switch B7 opens. The oil lamp H1 is switched off. At approx. 2000 r.p.m. the generator G2 takes over the
power supply and activates the charge rectifier G3. By that H2 is turned out.
Electric system Function C
G1 12V start battery
G2 12V generator in motor
G3 charge rectifier
M1 start motor with relay
S6 start switch
Y3/Y2 pull hold coil for the fuel supply of motor
B7 lubricating oil pressure switch for motor
H1/H2 pilot lamps oil pressure and battery charger

18 D_CON. 03GB.
Level screw
The engine shaft is
mounted on a gear
wheel, which through
the inside gearing
of the pump shaft is
reducing the number
of revolutions from
3000 to 1700 r.p.m.
Shaft toothed rim
Oil sleeve
Seal Roller bearing
Gasket Nut Circlip O-ring
Pump Function C
Gearbox
Seal
Oil fil-
ling
Mounting nut
Engine shaft
Gear wheel
Outlet

D_CON. 03GB. 19
125 03 47 - (03.2003)
AB
B
A
03K
Pump Function C
water quantity
regulation
safety valve
valve cone
The wobble disc is mounted directly on the gear shaft and yields at maximum pressure and water quantity
approx. 1725 rpm. By doing so it delivers approx. 19 (16 *) l/min. through the suction valve, the pressure
valve and the piston of the by-pass valve, where two through-holes make the necessary pressure drop
to keep the valve cone closed.
When water flow is interrupted, pressure rises, until the safety valve opens. Because of the achieved
pressure drop the valve cone is pressed to open, so that the water recirculates at a pressure < 10 bar.
Quantity of water is regulated by means of a screw pressing the cone to let some of the water recircu-
late.
safety valve
valve cone
water quantity regu-
lation
03K

20 D_CON. 03GB.
If the temperature gets too low there is a risk of condensation formation, and soot coating. If the tempe-
rature gets too high the efficiency will fall, and the surface of the pipe is loaded disproportionately with
damage as a result.
Conclusion:
The combustion process of the boiler is adjusted with 2 parameters, i.e. quantity of air and quantity of
oil.
In order to get a general view of where you are in the adjustment, it is necessary to measure the flue-gas
temperature and the CO2percentage in the flue gas.
In order to obtain the best combustion with the lightest loss, the quantity of air supplied is to be as exact
as possible.
Combustion process Function C
In the boiler the heating surface is approx. 2.1 m2, i.e. the surface of the boiler tube, which receives heat
from the buming oil.
As only a certain quantity of heat can be transferred per m2, when it is to be done in an efficient way,
it means that the amount of oil which is pumped into the boiler, just as the quantity of air, must be ac-
curately adjusted.
From the diagram below it clearly appears that the flue-gas temperature rises steeply, when the fired
quantity of oil is increased.