AR07.15-W-2000D | Test low pressure fuel circuit | 22.7.98 |
ENGINES 904.905 /906 /907 /921 ## up to 040487
W07.15-1014-09
1 Fuel delivery pump (KFP)
1.1 Pressure limiting valve in fuel delivery pump (9.2 bar)
1.2 Check valve in fuel delivery pump (0.2 bar)
2 Fuel filter (KF)
2.1 Fuel filter drain valve
2.2 Constant vent in fuel filter (as of engine end no. 027674)
3.1 Bypass from fuel feed passage to fuel return flow passage
5 Nozzle holder combination
8 Overflow valve up to engine end no. 002 604 6.5 bar
from engine end no. 002 605 4.5 bar
8.1 Constant vent (0.5 mm)
10 PLD unit pumps (Y6 to Y11)
12 Fuel prefilter (KVF)
12.1 Check valve in fuel prefilter
14.1 Assembly valve in fuel feed (opened by pressure)
15.1 Assembly valve in fuel return flow (opened by pressure)
17 Fuel tank
17.1 Air admission valve
18.1 Restrictor (0.5 mm) in flame fuel line
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18.2 Restrictor (threaded restrictor) in flame fuel line
19 Bypass line with valve
20 Fuel hand priming pump
21 Fuel heat exchanger
B10 Fuel temperature sensor
R3 Flame glow plug
Y5 Solenoid valve
Fuel circuit
A Fuel feed (inlet vacuum side)
B Fuel return (leak fuel)
C Fuel feed (pressure side)
D Fuel high pressure side (downstream of PLD unit pumps)
E Fuel return flow (fuel filter drain)
----- Fuel passages in crankcase
Fuel lines
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Test points, test data
G Manometer test
H Test for fuel return flow quantity
I Fuel pressure downstream of fuel filter
Idle speed: up to engine end no. 002604 6.0 bar,
from engine end no. 002605 4.3 bar
Limit speed: up to engine end no. 002604 6.2-7.5 bar,
from engine end no. 002605 4.0-6.5 bar
II Fuel return flow quantity at nozzle holder combinations
Test time: 5 min
Idle speed: oil moist
Limit speed: max. only drops
III Fuel return flow quantity at outlet of fuel filter housing
Idle speed and governed speed:
up to engine end no. 027673 0.1 l/min
as of engine end no. 027674 0.3 l/min
Fuel return flow quantity at overflow valve
Idle speed: up to engine end no. 027673 0.9-1.4 l/min
from engine end no. 027674 0.9-1.7 l/min
Limit speed: up to engine end no. 027673 2.0-4.0 l/min
from engine end no. 027674 2.7-7.5 l/min
IV Fuel intake pressure upstream of fuel pump
Idle speed: 0.09 up to 0.12 bar
Limit speed: 0.35 bar
V Low pressure fuel circuit leaktightness
Test pressure: 5.0 bar.
Test time: 5 min
Pressure drop 0.1 bar
W07.15-1016-06
Diagram of fuel circuit
1 Fuel delivery pump (KFP)
2 Fuel filter (KF)
3 Fuel feed passage to PLD unit pumps
4 Leak fuel duct
5 Nozzle holder combination
6 Pressure pipe connection
7 Injection line
8 Overflow valve
9 Fuel return flow passage purging fuel of PLD unit pumps
10 PLD unit pumps (Y6 to Y11)
11 Return flow leak fuel line
12 Fuel prefilter (KVF)
13 Fuel line to fuel prefilter
14 Fuel feed from fuel tank
14.1 Assembly valve in fuel feed
15 Fuel return flow to fuel tank
15.1 Assembly valve in fuel return flow
19 Bypass valve
20 Fuel hand priming pump
21 Fuel heat exchanger
A Fuel feed
B Fuel return flow/leak fuel
C Fuel feed (pressure side downstream of KFP and KF)
D Fuel high pressure side
Modification notes
23.5.05 | Banjo bolt for fuel line on cylinder head | Engine 904.9, engine 906.9 without | |
Banjo bolt for fuel line on overflow valve |
| Removing/installing | ||
Danger! | Risk of injury caused by being caught or pinched as cab is tilted | Ensure that no one is within the tilting range of the cab as it is being tilted. Always tilt the cab all the way to the end position and secure with the safety strut. | |
1 | Tilt cab | ||
| Notes on tilting the cab | Models 670-679 | |
2 | Remove side soundproofing on left | ||
Danger! | Risk of explosion caused by ignition of flammable products, risk of poisoning caused by inhaling fuel vapors or swallowing fuel as well as risk of injury to skin and eyes exposed to fuel. | No fire, sparks, open flames or smoking. Wear protective clothing when handling fuel. | |
3 | Carry out visual inspection of all fuel lines, screw connections and components | Run engine for about 2-3 minutes at limit speed. Replace damaged or leaking parts. Re-tighten screw connections if necessary. | |
4 | Inspect fuel prefilter element | Replace fuel prefilter element if necessary. | |
5 | Inspect fuel filter element | Replace fuel filter element if necessary. | |
6 | Connect diagnosis system | ||
| Connect hand-held tester and read out fault memory | All models | |
| Connect up STAR DIAGNOSIS and read out fault memory | Models 950-954, 957, 970-976 | |
7 | Increase parameter for stationary speed limit to 4000 rpm | Only engines fitted with stationary speed limit. Note limit parameterized. | |
Installation: reparameterize stationary speed limitation. | |||
Checking | |||
| Conditions for tests | Engine must be at operating temperature. Fuel temperature in fuel tank 40°C. Collect escaping fuel. The fuel which flows through during the test must be free of bubbles. | |
8 | Open cap on fuel tank | ||
9 | Test fuel pressure downstream of fuel filter | Attach test and measuring equipment to low pressure fuel circuit. | |
| Conduct test Up to engine end no. 002604 | ||
| As of engine end no. 002605 | ||
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10 | Measure fuel return flow quantity at nozzle holder combinations | Attach test and measuring equipment to low pressure fuel circuit. | |
| Conduct test | ||
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Injection line to pressure pipe connection and unit pump. | |||
Banjo bolt for fuel line on cylinder head. | |||
If the fuel return flow quantity is within the tolerance range, it is not necessary to conduct any further tests. | |||
11 | Measure the fuel return flow quantity at the engine | Attach test and measuring equipment to low pressure fuel circuit. | |
| Conduct test Up to engine end no. 027673 | ||
| As of engine end no. 027674 | ||
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Banjo bolt for fuel line on fuel pressure relief valve. | |||
12 | Test fuel inlet pressure upstream of fuel pump | Attach test and measuring equipment to low pressure fuel circuit. | |
| Conduct test | ||
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13 | Test low pressure fuel circuit in engine for leaks | Attach test and measuring equipment to low pressure fuel circuit. | |
| Conduct test | ||
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14 | Install in reverse order | ||
15 | Bleed fuel system | ||
16 | Test vehicle power output on dynamometer. | Only after all the tests or measurements have been carried out and any defects rectified: | |
If no improvement in fuel consumption or performance has been achieved, connect a fuel consumption measuring system. |
Diesel injection system with unit pumps (MR/PLD)
Number | Designation | Engine Engine | ||
BA07.15-N-1004-01A | Injection line on pressure pipe connection and unit pump | Nm | 35 | |
BA07.15-N-1006-01A | Banjo bolt for fuel line on cylinder head | Nm | 50 | |
BA07.15-N-1007-01A | Banjo bolt for fuel line on overflow valve | Nm | 50 | |
000 589 68 03 00
High pressure hose
Ring wrench socket
Ring wrench
Tester
000 589 07 03 00
123 589 04 21 18
617 589 04 21 00
541 589 00 91 00
Adapter parts
Tester
541 589 02 21 00
Referenced documents
- ad0000w200003a Connecting hand-held tester (HHT), reading fault memory
- ad0000w200004a Connect STAR DIAGNOSIS and read out fault memory
- ad0715w700101d MR (PLD) test of hydraulic system fuel pressure downstream of fuel filter
- ad0715w700101f Fuel pressure downstream of fuel filter, MR. (PLD) hydraulic testing
- ad0715w700103d MR (PLD) test of hydraulic system fuel intake pressure upstream of fuel pump
- ad0715w700106d MR (PLD) test of hydraulic systems fuel return flow quantity
- ad0715w700106f MR. (PLD) test of hydraulic system fuel return flow quantity
- ad0715w700107f MR (PLD) test of hydraulic system fuel return flow quantity at nozzle holder combinations
- ad0715w700108d MR (PLD) test of hydraulic system low pressure fuel circuit leaks
- ah6080n000301a Notes on tilting the cab
- ar0715w200001i Install test/measuring equipment in the low pressure fuel circuit
- ar0715w200001l Install test/measuring equipment in the low pressure fuel circuit
- ar0715w200001n Install the test/measuring equipment in the low pressure fuel circuit
- ar0715w200001p Installing test/measuring equipment in low pressure fuel circuit
- ar0715w200001s Installing test/measuring equipment in low pressure fuel circuit
- as4700z000101a Risk of explosion caused by fuel igniting, risk of poisoning caused by inhaling and swallowing fuel as well as risk of injury to eyes and skin caused by contactwith fuel.
- as6080z000101a Risk of injury caused by body parts being pinched or crushed as cab is tilted
- wh0730lkw0000x 0730 - Fuel prefilter - Cleaning filter cartridge All engines
- wh0780lkw0030x 0780.30 - Replacing fuel filter cartridge Engine 904 LA