SERVIC SERVICE E B ULL ETIN ETIN Kobelco Construction Machinery Co., Ltd. Technical Service Group, C.S. Department. Authorized by;
Issued by;
CS Dept. May.27,2009 Sakutani
CS Dept. May.27,2009 Iwata
CLA SSIFICATION SSIFICATION : IMPROVEME IMPROVEMENT NT
Issue Date Bulletin No. Subject
: May 27th, 2009 : S030-30-K010 : Injector Diagnosis Function "Z010" (New function)
Applicable Area Applicable Model Applicable S/No.
: All : SK200-8Mi/c, SK250-8Mi/c, SK250-8Mi/c, SK330-8Mi/c, SK460-8Mi/c SK460-8Mi/c : YN12-56001up, YN12-56001up, YQ12-08001up, LQ13-07001up, LQ13-07001up, LL13-06001up LL13-06001up LC11-08501up, YC11-04501up, LS11-02501up, YS11-02001up
Subject: Injector Diagnosis Function “Z010” 1. Background of Information The injector diagnosis function is newly added starting with Geospec minor change model for preventive fail/damage of common rail parts and/or engine component. The monitoring function is as follows, (1). Controller monitor the common rail pressure after turning off of the engine key switch. (2). The error code "Z010" indicates on the cluster gauge monoitor, if common rail pressure drop faster than standard value. The error code "Z010" alerts against occurrence of a potential severe malfunction in shortly (e.g. engine breakage). When the code “Z010” is displayed, check t he system by following the instructions shown below. (This new function does not not cover the machines before minor minor change. This is because there are no interchangeability of controller between after and before minor change.)
2. Function of diagnosis With a new engine/injector, the common rail pressure decreases to 10 MPa approx. 6 sec. after turning off of the engine key switch. In comparison to this longer time, the common rail pressure decreasing time on machines (with faulty injector) found on the market was typically 1.2–1.6 sec. Therefore, detection time standard is set to the value as shown below. Model Detection standard 20-ton Decreasing time to 10 MPa is max. 2.0 sec. 25-ton Decreasing time to 10 MPa is max. 2.0 sec. 30-ton Decreasing time to 10 MPa is max. 2.0 sec. 45-ton Decreasing time to 5 MPa* is max. 2.0 sec. * Key switch turn t urn Off while the engine is running at low idling after complete warming up. * The common rail pressure of the 45-ton model drops to 30 MPa during low idling (45-50 MPa with other models) - reason for setting to 5 MPa.
3. Checking Procedure when the code"Z010" is displayed (I) Failure detection The error code “Z010” is displayed on the cluster gauge and the buzzer beeps (The off period of the cluster gauge power after the key-off, upon detection of the first failure, is 20 sec. The power off period after the second and subsequent failure detection will be shorter than 20 sec.) (II) Checking procedure 1. Check the fuel line to make sure that no leakage* from pipes and that the common rail pressure sensor is active. * While the engine is running at low idling, verify that No. 28 display “ENG oil pressure” (common rail pressure) on the service diagnostic screen is in the following standard limits. → Standard limits: 20t, 25t and 30t: 45-55 Mpa, 45t: 25-35 MP 2. Check the fuel filter for clogging, fuel tank for excessive deposition of contaminant, and hose for damage; and take corrective measures (e.g. cleaning, replacement) as necessary. 3. When steps 1 and 2 are successively done, measure the common rail pressure decreasing time after engine stop with Hino DX. a) Connect DX, select data monitor signal and common rail pressure. b) Start the data monitor at engine low idling (warmed up). c) Stop the engine and then immediately turn on the key switch (to continue DX communication). d) Immediately after engine stop, start measuring of time until the common rail pressure drops down to 10 MPa. e) If the common rail pressure has dropped to 10 MPa within 2 sec., the injector may be faulty. * For reference, data (common rail pressure, engine speed and fuel temperature) taken on a new vehicle are shown below. (The graph shown below is prepared.)
4. If the common rail pressure has dropped to 10 MPa within 2 sec., the injector may be faulty and need replacement. The diagnosis function"Z010" and measurement (II)-3(common rail pressure decreasing time) can not judge the cylinder number of failed/damaged Injector(s). The following procedure (a), (b) and ( c) is guide line of judging cylinder number of f ailed/damaged injector(s), although they may not be reliable checking method depending on characteristics of failure. a) When using DX data monitor FCCB correction final value. (for 20/25ton : 1-4 cylinders, for 30/45ton : 1-6 cylinders) ; 1) Connect the DX. Select "Data Monitor" through the "View" menu. 2) Select "FCCB correction final value(#1 to #4or#6)" from parameter select menu. (FCCB : Fuel control cylinder balance) 3) In the service adjustment mode 1, turn on the "Check Injector", and start the engine. 4) Start the data monitor. 5) On each cylinder, make comparison of the final injection quantity. If the amount of injection for a particular cylinder significantly differs from those of other cylinders, replace the injector for that cylinder. (Reference value±10 mm3/st) b) When using active test: 1) Connect the DX. Select "Active Test", through the "Check function" menu. 2) Cut out the each injector for the first cylinder to last cylinder and check the changes in the exhaust gas condition. (Detection of changes is verify difficult unless the injector is completely malfunctioning and exhausting raw gas.) c) When using nozzle tester: 1) See Fig. 1. Attach the injector to the nozzle tester. 2) Operate the handle to send the fuel to the injector until the pressure reaches 20 MPa (Fig. 2). 3) If the pressure is more than 20 MPa, wait until it decreases just to 20 MPa and then start counting. Read and record the pressure every 10 sec.: final recording should be made at 120 seconds.
4) Plot the measurements on a graph. Repeat measurement and record for all cylinders. 5) Compare the records with those on Table 1 and Fig. 3 (showing measurements taken with normal injector). If the pressure decreasing rate of a particular cylinder is significantly faster than the standard rate, replace the injector for that cylinder. Table 1 Decrease of pressure over time (MPa) (sec)
1st (MPa) 2nd (MPa)
10 20 11.5 8.0 11.0 7.5
30 7.0 6.2
40 6.0 5.5
50 5.5 5.0
60 5.1 4.8
70 5.0 4.5
80 5.0 4.1
90 4.9 4.1
100 110 120 4.5 4.3 4.2 4.0 4.0 4.0
5. After replacement of injectors, be sure to rewrite the injector corrective value to ECU and perform "Check Injector" 6. When the replacement of the injector corrects the problem, no error code will appear upon turning on of the key switch.
(III) Notification to user Many injector failure problems are caused by the bad quality(contaminated) fuel. Check the fuel supplying method and fuel controlling practice (element replacement interval, removal of tank rust, etc.). If the results of checking are poor, give the user instructions describing correct fuel control procedure.
